Jennifer Scott

5 Oct 2009

A community academy, serving 1,400 students, has just installed a new wireless local area network (WLAN).

Shelfield Community Academy in Walsall has deployed an Extricom WLAN by working with G4 Networks. The implementation is part of its "technology for learning" strategy, which aims to offer students good online access of rich media in a very high demand environment.

It will also support extra services such as IPTV for both staff and students to aid learning.

Russ Nicholson, assistant principal at the academy, said in a statement: "Migrating to a wireless network is a significant investment for the academy. Over the next few years, it will support the majority of operational and learning applications."

He added: "So the WLAN we deployed had to demonstrate performance and high capacity such that the user experience matched that of a wired network."

The project is a multi-million pound upgrade which will also include voice over WLAN for the entire campus.

The original version of this article may be viewed at the ITPro website. 

Sam Trendall
CRN

25 Sep 2009

The networking channel is banking on the ratification of the wireless LAN (WLAN) 802.11n standard to give it a shot in the arm.

The IEEE formally ratified all 11n amendments to wireless standards earlier this month, more than six years after predecessor 11g was given the green light. One of the 11n's key developments is the addition of multiple-input multiple-output (MIMO) channels.

Phil Belanger, marketing and business development director at vendor Extricom, claimed that assurances of backwards compatibility were crucial for businesses that have already deployed the 11n standard.

He said the ratification may drive up sales outside WLAN's public sector stronghold. "Maybe now more types of industry will be accepting of 11n solutions," he added.

"The ratification removes potential obstacles that may have lingered at the back of the mind for some enterprises."

Belanger claimed the technology's intricacies would provide "challenges and opportunities" for VARs.

"Coming up with solutions and explaining them to customers is the challenge," he said. "The opportunity is to add value; they can use 11n to solve problems in specific vertical industries."

Bruce Hockin, head of business strategy for distributor Avnet Technology Solutions, claimed 11n was far less complex than people believed.

"People have been tentatively figuring out their own versions and no one has gone to town on 11n because they were worried about interoperability," he added.

"This will open up more opportunities for the channel, due to increasing confidence in the technology."

But some onlookers felt the ratification was little more than a formality. Keith Humphreys, managing consultant at euroLAN, said: "I am sure most customers thought it was already ratified."

The original version of this article may be viewed on the CRN website. 

Alex Scroxton
Microscope.co.uk

The wireless 802.11n standard has finally been passed by the Institute of Electrical and Electronics Engineers (IEEE) after seven years of work.

The standards were originally mooted in 2002 and the draft was first released by the IEEE a year later. Since 2007 the vast majority of wireless equipment on the market, including routers, wireless-enabled laptops and netbooks and so on has been compatible with the draft standard.

Although 802.11n kit has been shipping for two years, up until now the channel has been unable to guarantee their customers that past product releases would be compatible with the standard, or future kit compatible with installed estate, instead relying on vendor goodwill to ensure everything worked correctly.

"The channel can now make a very strong case that the equipment will remain compatible," said Phil Bellanger, vice president of marketing and business development at WLAN vendor Extricom.

"They can offer their customers that assurance, and in general vendors have understood the importance of that," he added. "Wireless resellers are now in a very solid position."

While work has already begun on a future standard that is expected to offer much higher throughput in a higher frequency band, but Bellanger said there would be no cause for concern, as the 802.11n standard will remain relevant for a long time to come.

"I believe we're going to see at least two further waves of innovation around 11n. In another six months we will begin to see the first wave of fully-compliant products," Bellanger said.

He also reassured those concerned with the length of time taken to ratify 802.11n, noting that having taken considerable flak over its tardiness, the IEEE was taking steps to speed up the process in future.

The original version of this article appeared in the Microscope website on 15 September 2009.

Phil Belanger, VP marketing and business development, Extricom

Published on August 9, 2009

What is 802.11n?

"802.11n is the latest standard developed by the Institute of Electrical and Electronics Engineers (IEEE) 802.11. 802.11 is a group of standards delivering wireless local area network (WLAN) connectivity in the 2.4, 3.6 and 5 GHz frequency bands.

802.11n is the output of work from the ‘High Throughput Working Group' of 802.11. This group produced a new standard of speed that increases the raw data rate of 802.11 wireless networks from 54 megabits per second up to 600 megabits per second. There are also many other improvements to the standard and the underlying technology."

Where did it come from?

"The IEEE Standards Committee (IEEE 802) developed the wireless LAN standard known as IEEE 802.11. The Committee has also developed standards for Ethernet (802.3), Token Ring (802.5) and others. Specifically, 802.11n is the biggest change to the 802.11 family of standards since its inception in 1997."

What's all the fuss about?

"802.11n will have a huge impact on the wireless LAN industry and expand the market for 802.11 based products. For example, consumer electronics will be able to have ubiquitous wireless connections that are capable of delivering multiple, high definition video and audio streams throughout a household to a variety of compatible devices such as iPhones, TVs, PCs and entertainment systems.

From a business point of view, the standard could also deliver enough bandwidth to enterprises so that they no longer need a wired network connection at every employee desk. In the future, wireless LANs may become the primary way to connect to corporate networks rather than a mobile overlay network."

What will 802.11n mean for end users?

"The standard will enable a greater diversity of Wi-Fi products, with varying price structures and performance capabilities, making wireless solutions far more accessible. Additionally, 802.11n will ensure that the Wi-Fi network is more reliable and suitable for a larger variety of applications."

What is the potential for resellers make money from it?

"Wireless LANs in the enterprise are no longer a commodity; the 802.11n standard changes everything. There will be many opportunities for resellers to deliver value by designing networks that match the application requirements, whilst providing the appropriate quality of service.

Access Point placement, power levels and channel selection are completely different with 802.11n, therefore cookie cutter designs and approaches to selling 802.11n will not work. Instead resellers should advise their customers to take on a migratory approach to adopting the standard. Resellers can add value by planning a network that will be able to benefit from the new standards capabilities and support legacy Wi-Fi devices whilst staying within a reasonable budget."

What are the misconceptions and myths of 802.11n?

"One misconception is that 802.11n is just an increase in speed. This is not the case; there are many new improvements that are unrelated to the standards' speed benefits. For example, the most significant change is the improved reception of a Wi-Fi signal within a coverage area. Well designed 802.11n networks will also be more reliable and robust than earlier Wi-Fi networks.

Other misconceptions are:

• The standard is completed - NO! The standard has not been officially ratified, though it is expected to be formally published in autumn this year.
• All 802.11n products go faster than 802.11g products - This is not necessarily the case, and depends on which features you enable. To achieve the maximum 802.11n speed, for example, both client and infrastructure are required to support ALL of the enhancements and new features. With so many legacy clients still in use though, it's more likely organisations will want to sweat their existing investment and gradually introduce 802.11n clients onto the network. This migratory approach means the majority of networks will continue to operate at the 802.11g data rate for many years to come.
• All 802.11n products go 600 Mbps - 600 Mbps is the maximum data rate for products that support double wide 40 MHz channels and 4 simultaneous streams. The current shipping product (802.11n Draft 2) supports 2 simultaneous streams in 40 MHz channels."

The original version of this article appeared on the Channel Pro website on August 9, 2009.

802.11n is the most significant change since the 802.11 standard emerged, with across the board changes, including the physical and MAC layers, modulation and antennas. Enabling the standard is an Herculean task, with proposals from the volunteer group meetings eliciting thousands of comments, each resolved either by a written response declining it or text explaining its inclusion.

Along with the logistics, there are the usual politics and manoeuvrings, but the Alliance began certifying draft 11n products in summer 2008, lessening the risk for developers. 11n offers an acceptable level of interoperability between 11n devices - plus backwards compatibility with 11a/b/g, so a smooth migration to 11n should be possible. The date for 802.11n ratification is September 2009, promising a dramatic leap forward in capability: up to 300 Mbps raw data rate, up to four data streams, improvements in modulation from 54Mbps to 64 Mbps at 20 MHz, plus channel bonding (taking two defined channels and combining them, doubling the data rate to 40 Mbps).

Phil Belanger is a veteran of wireless broadband and known in much of the media as “Mr Wi-Fi”. A founder and one-time chairman of the Wi-Fi Alliance, a hands-on mover and shaker in the industry for over 25 years and now marketing and business development chief at “channel blanket” proponent Extricom. He is also a pragmatist: “As an industry, we risk over-hyping the capability and focusing too much purely on speed improvements. In reality, there is a range of speeds possible and I am concerned that the market will view that as disappointing at first sight.

“It is tempting to focus on the Mbps, but 802.11n is a complex animal. It can deliver improved range and coverage, but it is impossible to give a definitive answer for all circumstances: much still depends on the distance from the AccessPoint [AP].”

What is impressive however - he describes it as “fabulous” – is the backwards compatibility as a requirement of the standard: “Today 11n is pushed most strongly in consumer environments, which is where the early success are. High-end laptops now have 11n built in. 11n is definitely a positive experience from the consumer perspective. I put an 11n router in my house and found it worked at a similar speed to my legacy 11a/b/g products but at a far greater distance; an 11n client running on a legacy infrastructure will perform as well as the best a/b/g client, too.”

Give us the tools

Enterprises are, understandably, proving slower to adopt 11n - apart from education and, to a lesser extent, healthcare. There are important planning and control issues to consider – even wired network challenges because 11n amounts to a system at the edge of the wired network delivering several hundred Mbps and there is no uniform 11n client with a single performance profile: “It works beautifully, but it does mean we have to change how we plan and build enterprise networks, otherwise there is the possibility of bottlenecks elsewhere in the wired network and overloads.”

Using 11n’s MIMO (multiple input, multiple output) feature, the coverage pattern of 11n APs is unpredictable as each AP’s coverage area is erratic due to the way 11n works; if you fill in all the coverage “holes” by turning up the power, it attracts co-channel interference. Belanger highlights the need for new tools for tuning an design to meet the challenge of 11n: “The AP coverage pattern will be different for each client type, making AP cell planning as much an art as a science. Equipment providers and integrators are just beginning to learn best practice for 802.11n”

As to the choice between 2.4 GHz and 5 GHz, Belanger points out that most enterprise APs use 11n radios that can tune to either band, although not dynamically, so it is an important choice. The Extricom system in the 2.4 GHz band (with three non-overlapping channels), for example, could use 2 x 40 Mbps and 1 x 20 Mbps for legacy; at 5 GHz there are more channels available but more variables as to performance, such as walls and distance.

Security blankets

Extricom favours its channel blanket (rather than a micro-cellular) AP architecture, controlling the APs via a centralised switch. The approach advocates configuring 11n’s three non-overlapping channels at 2.4 GHz to offer three independent “blankets” operating independently, so one could be exclusive to public internet access, for example, or for encrypted data on an entirely separate VLAN and WLAN.

Belanger says that while is not part of the 802.11n standard, the approach is complementary with 11n’s spiky pattern AP coverage challenge, with adjacent APs on the same channel, lots of overlap and the central switch eliminating co-channel interference. The APs are at the physical layer while the MAC layer is controlled by the central switch, coordinating the actions of the APs and not allowing adjacent APs to transmit at the same time.

One other player advocates putting all APs on a single channel: Meru Networks. While Extricom tackles it fundamentally in hardware, Meru is primarily a software solution. “There is no standardisation of how to make APs work together – that’s the added value with a channel blanket approach. Figuring out where to place the APs and shape the antennas is the artistic part,” adds Belanger.

The advent of 11n does offer the prospect of wireless shifting from a casual, subset network in the enterprise to mainstream technology across many sectors. It is already critical in healthcare (medical telemetry, portable X-ray machines, RFID, for example).

The UK education market is also likely to be a rich seam for 11n, particularly with universities wanting to differentiate in their competition for students. At the 900-student Essa Academy in Bolton, for example, the blanket WLAN supports streaming voice, video and data applications and underpins the roll-out of Apple iTouches to each student when term begins in September 2009.

The original version of this article can be viewed on IP Leaders website . 

John Cox
Network World

Extricom has unveiled draft 802.11n wireless access points both less than $1,000, that will let customers run 802.11n in either or both the 2.4GHz or 5GHz bands, while using separate radios to support existing 802.11bg and 802.11a clients.

Unlike a number of rivals, the Extricom access points can draw all the power they need from existing 802.3af power-over-Ethernet systems, without affecting 802.11n throughput or range.The result is an affordable device that can be substituted for an existing 2.4GHz WLAN access point, without redesigning the WLAN layout or changing access point positions, at least at first.

So corporate sites can phase in 802.11n with minimal disruption, says David Confalonieri, vice president of marketing and strategy, for Extricom. As companies begin using the 5GHz band, which doesn't reach as far as the 2.4GHz band, additional Extricom access points would have to be added, and some existing ones might have to be shifted, he says.

The two access points are the EXRP-30n, with two 802.11abgn radios and one 802.11abg radio, and integrated antennas; and the EXRP-40En, with two 802.11abgn radios, and two 802.11abg radios, with antennas packaged in a separate, flat, plastic rectangle, called the antenna bar, cabled to the access point. Each 802.11n chip support two spatial streams, each with a data rate of 150Mbps, over three transmit and three receive antennas (known as 3x3 MIMO).

The Extricom wireless LAN switches now have updated software to support 802.11n. Security is based on the Wi-Fi Protected Access 2 (WPA2) specification. One radio in either device can be dedicated to continuous radio frequency monitoring to detect rogue wireless devices. The entire system can operate fully on standard 802.3af PoE. (The only other vendor making that claim is Siemens.)

By replacing a group of existing access points with the new Extricom units, an enterprise could support today's 802.11g clients on one 20MHz, 54MHz in the 2.4GHz band, by means of one 802.11abg radio. Because 802.11n clients today also are in the 2.4GHz band, the Extricom access point can combine the two remaining 20MHz channels into one 40MHz, 300Mbps channel on a separate 802.11n radio, and dedicate it to 802.11n clients. The same kind of segregation is possible in the 5GHz band.

With the same physical access points, Extricom can create three or four separate, non-interfering WLANs that span an entire site, and dedicate each one to different clients or traffic types or user groups. Its approach is broadly similar to that of rival Meru Networks. Both vendors can assign the same channel to radios, eliminating the need to juggle channel assignments among access points. And both give the access points or switches more control over where and when clients associate and transmit.

In Extricom's case, all of the 802.11 logic is centralized on the switch, with the access point being reduced to just a group of radios and antennas. According to Extricom, there is no software on this "ultra thin" access point.

One added benefit of this approach is that it eliminates power-hungry CPUs from the access point, dramatically reducing the amount of electricity needed. That's a big reason why the Extricom 802.11n access points can run with existing 802.3af PoE systems, according to Confalonieri.

The access points will be available in June or July. The four-radio model is priced at $995 and the three-radio model at $895.

The original version of this article can be read online at the NetworkWorld website.

Peter Judge
Techworld
25 March 2008

Enterprise Wi-Fi vendor Extricom has launched an 802.11n switch, claiming its "blanket" Wi-Fi technology solves the power problem of the new standard, allowing a smooth transition to faster Wi-Fi.

"Other vendors' implementation plans for enterprise-class 802.11n abandon the 2.4GHz band, move to the 5GHz band, and require costly non-standard power-over-Ethernet schemes," said David Confalonieri, vice president of marketing at Extricom. Extricom's "blanket" architecture avoids all these problems, he said, and supports four radios in one access point (AP).

Although the draft 802.11n standard offers a substantial speed increase over today's Wi-Fi, most vendors have been unable to make a full implementation, using two radios and multiple antennas, which uses less electrical power than the maximum of 12.95 watts which can be provided using the power-over-Ethernet standard with which enterprises drive their APs.

Only Siemens has apparently solved the problem for a two radio access point, while other Wi-Fi vendors have offered different work-arounds including proprietary power-over-Ethernet, and tuning back the throughput of the access point.

Extricom can vault past that, because its blanket architecture - which puts all access points on the same radio channel - centralises more of the processing. "Our AP has no CPU," said Confalonieri. "We can offer four radios and use less than 6 watts." Extricom's four-radio N access point is a new version of quad-radio 802.11abg APs launched a year ago.

Despite this, Extricom suggests companies should introduce N in stages, especially in the 5GHz band which has rarely been used for Wi-Fi till now, and whose propagation differs from the normal 2.4GHz band. Extricom says its systems can provide full N coverage and support legacy 802.11b and 802.11g using only the 2.4GHz band, because every access point uses the same channels - in contrast to "cell-planning" systems from Cisco Aruba and Trapeze, where adjacent APs have to use different channels.

This leaves the 5GHz band empty for gradual deployment. "You can introduce a slow roll-out of N, without changing the real estate, until your business has clients which require 5GHz N," said Confalonieri.

"The 802.11n standard promises to play a pivotal role in finally making the all-wireless enterprise a reality," said Stan Schatt, director of wireless connectivity at ABI Research.

 "The implementation of 802.11n should be about evolution, not revolution," said Gideon Rottem, chief executive of Extricom, who has said cell-planning is the 'original sin' of Wi-Fi.

The EXRP-40En four radio access point includes two n/a/b/g radios and two a/b/g radios, which can be operated in any combination of channels and bands. The ‘n' equipped radios support 3x3 MIMO (multiple-in, multiple-out) antenna configuration. Extricom has also launched a tri-radio AP, with two 'n' radios and one a/b/g radio.

A firmware upgrade can give existing Extricom switches the ability to support the new APs, and a new switch, the EXSW-1600 has been announced, along with an antenna bar, which can add more antennas so one AP can have up to twelve antennas on a wall-mounted bar, connected to the AP by a single cable.

The original version of this article can be read online at the TechWorld website.

Dave Bailey
IT Week
25 Mar 2008

Communications vendor Extricom has launched new 802.11n hardware, which it claims will allow firms to obtain all the performance benefits of the wireless Internet standard without the set-up hassle.

Extricom's new hardware includes enhancements to Extricom's 'Channel Blanket' architecture allow Extricom's current customers to add 802.11n to their WLAN, by a simple firmware upgrade to the central controlling switch.

It has also started shipping two new wireless access points: the EXRP-40En four-radio UltraThin AP, which Extricom say is the industry's only quad radio 802.11n AP; and the EXRP-30n three-radio UltraThin AP.

"Customers flock to the table when they hear about the performance possible" by upgrading to 802.11n equipment, said Extricom's marketing vice president, David Confalonieri. "However when they learn what they have to do - they back away. At Extricom, we're hoping they'll stay for dinner."

One of the benefits of Extricom's approach is that it centralises the control of wireless protocols in the switch, said Confalonieri. The APs have only transmit and receive functions, no storage capacity, and don't even have an IP address, a feature which means the user's system is not continually 'handing-off'. This makes the process of planning coverage far easier, Confalonieri added.

Traditionally, WLAN coverage depends on a cell-based approach, that requires IT managers to plan which areas access points can cover. When users move around, the system has to hand off the client to the relevant access point. In this model, there is an "implicit assumption that IT managers need specific radio-frequency expertise," said Confalonieri. With 802.11n, cell planning becomes even more complex, he argued.

Extricom's model lets the switch make all the decisions on wireless packet delivery and just takes wireless data from the radio which is receiving the strongest signal from the user.

Confalonieri said another major advantage of Extricom's system was that 802.11n devices and legacy (802.11a/b/g) devices at 2.4GHz don't interfere, so firms didn't need to limit 802.11n devices to the 5GHz frequency band and leave the 2.4GHz only for legacy devices.

Its EXRP-40En has two n/a/b/g radios and two a/b/g radios. These can be used in any combination of channels and bands.

The EXRP-30n is a tri-radio 802.11n AP with integrated antennas, allowing for easy deployment of ‘n' on a large scale - it has two n/g/b/a radios and one g/b/a radio. The 'n' equipped radios have a 3 x 3 multiple-in, multiple-out (MIMO) antenna. "So, out of the gate we can run two 'n' WLANs and two 'non-n' WLANs side by side," added Confalonieri.

The original version of this article can be read online at the ITWeek website.

Andrew R Hickey, ChannelWeb
Tue. Mar. 25, 2008

Wireless networking vendor Extricom on Tuesday unveiled a new suite of products based on the 802.11n draft 2.0 WLAN standard, joining the ever-growing lineup of vendors capitalizing on the increased range and throughput the latest Wi-Fi standard offers.

Extricom, which now joins the ranks of other vendors like Cisco Systems (NSDQ:CSCO), Meru Networks, Ruckus Wireless, Motorola (NYSE:MOT) and a host of others, released a set of products including two new access points and a new antenna bar. Extricom also updated two of its WLAN switches and added a new wireless switch.

This is Extricom's fourth-generation solution and offers disruption-free and full-performance 802.11n for the enterprise, operating on both the 2.4 GHz and 5 GHz Wi-Fi bands.

According to Extricom, 11n solutions available to date leave the 2.5 GHz band for use by only legacy devices and require non-standard Power over Ethernet (PoE) schemes, while Extricom's WLAN System, based on its Channel Blanket architecture avoids these deployment obstacles.

"We're giving our channel partners and customers the ability to run full-performance n in 2.4 and 5 GHz," said David Confalonieri, the Israel-based vendor's marketing vice president. Confalonieri added that most companies today run wireless networks in 2.4 GHz, but most 11n solutions only work on 5 GHz. Utilizing both bands, he said, gives them the freedom to grow and protect their current investments.

"Get started today and have the flexibility of both bands going forward," he said.

Extricom's solutions combine multi-radio access points for parallel, simultaneous wireless networks from the same set of APs. The overlapping networks, which Extricom calls its blanket architecture, can operate on any combination of channel, modes and frequency bands, allowing network managers to allocate each WLAN to a specific user group, application or type of device.

The method, Confalonieri said, lets users introduce 11n devices gradually into their existing environment without having to forklift and without conflicts with legacy devices. 11n can also be deployed with 40 MHz channel bonding in both 2.4 GHz and 5 GHz to receive data rates of 300 Mbps, even if 11g or 11a devices are still present.

Confalonieri added that the existing network can also be augmented with the benefits of 11n without having to rework the number, location and cabling for access points. In addition, conventional 802.3af PoE can still be used, because Extricom's UltraThin design doesn't require a processor, instead standard PoE can drive a four-radio access point at full rate and coverage. Lastly, Confalonieri said, Extricom's 11n suite gets rid of the complexities of cell planning.

"The implementation of 802.11n should be about evolution, not revolution," said he said. "11n should be an enhancement, something you add to your existing environment, not something you migrate to, not something you replace your existing investment with."

On Tuesday, Extricom released the EXRP-40En, a four-radio UltraThin access point, which incorporates two 11n/a/b/g radios and two a/b/g radios. They can be operated in any combination of channels and bands. The vendor also released the EXRP-30n, a tri-radio UltraThin access point with integrated antennas. The EXRP-30n has two 11n/g/b/a radios and one 11g/b/a radio, which can also be operated in any combination of channels and bands. All Extricom 11n equipped radios incorporate 3x3 MIMO (multiple input, multiple output) antenna configurations.

The vendor also unveiled updates of two of its WLAN switches to support 11n access points and released a new WLAN switch with 11n support. The 12-port EXSW-1200 and 24-port EXSW-2400 WLAN switches will require new firmware to support the new 11n access points, but will require no hardware upgrades. The new switch, the 16-port EXSW-1600 offers flexibility and scale, by offering a new port account for companies looking to deploy 802.11n.

"The switch family will be able to drive and operate with the exiting lineup of access points and the new 11n access points," Confalonieri said.

Lastly, Extricom unveiled the EXAN-10 Antenna Bar. Since MIMO technology multiplies the number of antennas for each Wi-Fi radio, which creates an unsightly number of external antennas that have to be connected to the access point. Extricom can integrate up to 12 antennas into one assembly, meaning numerous antennas can be connected to the access point with one single cable run to the antenna bar, which is then wall mounted.

For VARs, Confalonieri said, the suite of 11n products that run on Extricom's blanket architecture lets solution providers engage customers without making them refresh and restart their WLANs, a strong bargaining chip when some 11n products require replacing existing wireless infrastructure.

"It leapfrogs over the hurdles that have been nagging at channel partners that are trying to move their customers to 11n, and they're the ones charged with implementing it," he said.

Frank Kobuszewski, vice president of the Technology Solutions Group at Syracuse, N.Y.-based solution provider, CXtec, an Exticom partner, said Extricom's entrance into 11n gives him an alternative to offer to customers that will help them do more with their current wireless infrastructures while also embracing new technologies.

"That adds on to our value proposition," he said.

While Extricom launched its partner program last month, Kobuszewski said he's been actively getting the word out about the vendor's technology and its approach to wireless networking. He added that he's started to build solutions around it and is ramping up.

"It's definately an alternative to the 'me too' way of networking," he said. "It seems to be a win-win."

The original version of this article can be read online in the March 25, 2008 issue of ChannelWeb

Michael Morisy, News Writer
SearchNetworking.com
February 21, 2008

For enterprises seeking to move their Wi-Fi access from best-effort to mission-critical, so-called fourth-generation implementations, from such companies as Meru and Extricom, have been making inroads and could offer more consistent wireless access.

"I think from a deployment standpoint ... fourth generation makes a lot of sense to me, particularly from very dense environments," said Michael King, research director at Gartner. "It makes even more sense in the .11n side of the world."

That is because 802.11n, the upcoming standard for wireless access, will allow greater throughput and range, as well as some more business-minded features (including tightened security), raising the possibility that some enterprises will ditch Ethernet entirely for an almost completely wireless LAN.

So what exactly is fourth-generation Wi-Fi? Today, most wireless access points (APs) are carefully placed to create circles of slightly overlapping Wi-Fi coverage, each on a different frequency channel. This means that each time a laptop moves from one room to another, for example, the wireless connection must be momentarily broken and rebuilt on the client end.

King noted, however, that improvements in third-generation technology made these AP handoffs minimal enough almost not to matter in many deployments. "It's not black and white," he said of the benefits of switching from third-generation to fourth-generation offerings. "[Third-generation vendors] have methodologies of channel switching that work just fine."

Fourth-generation APs, currently developed by Meru and Extricom, use a smart, centralized controller to create a large, virtual wireless cell that spans several APs, making the handoff between cells transparent to endpoint devices such as laptops and, ideally, reducing dropped connections as a user moves around a wireless LAN. As far as the device can tell, an entire office is just one large wireless zone (see sidebar for a look at the other wireless generations).

Extricom's APs have much less intelligence than typical offerings. They act similarly to antenna extensions that are intelligently tuned in to the appropriate device by a central switch to which each AP is directly connected. Meru's devices, on the other hand, have more intelligence in the AP, allowing them to communicate to the network on layer 3.

Each company claims its technology is superior in several ways, but King said they were similarly capable for most tasks.

These fourth generation methods also have the benefit of reducing planning complexity -- no more careful spacing of APs at set intervals, overlapping - but not by too much - connectivity zones to provide maximum range and throughput. Instead, these options can pack APs more closely to ensure stronger cover without the fear of radio interference.

But is it time to jump aboard? Maybe, maybe not. King said the technology is promising, but it is so new that network architects don't understand all its pitfalls.

"There can be some drawbacks in terms of processor power," he said. "But overall, I don't see a real huge downside doing it on the fourth-generation side versus the third-generation side."

King said he did not see a huge upside either, particularly if an enterprise could upgrade its existing infrastructure less expensively. Ultimately, he said, the market for wireless equipment was growing fast enough to support the two fourth-generation providers as well as the current third-generation providers, with plenty of customers to go around.

These fourth-generation technologies are not particularly new, but they are starting to get scrutinized from a broader market, particularly as 802.11n makes wireless a more viable replacement for traditional Ethernet office connections.

Meru was the first to deploy its technology, in 2003, and it still holds the dominant position over Extricom.

"From day one, we borrowed some of the principles of how the wireless LAN should operate from the cellular industry," said Rachna Ahlawat, vice president of strategic marketing at Meru.

At that point, Ahlawat said, most existing wireless office networks were using consumer-grade technology, which offered convenient use of Wi-Fi access based around various points of deployment: a boardroom, a cafeteria, but not necessarily the whole office.

Meru sought to change that paradigm, betting on a future where enterprises demanded more pervasive access.

"That's when we came up with this approach of putting all access points on one channel," Ahlawat said. "Our virtual cell approach allows the controller to initiate the roaming. That's why it doesn't matter if there are five people connected or a hundred, because the system manages the load."

Because AP coverage overlaps, end connections can be divvied up among nearby APs as needed without the end user's intervention or awareness. This overlapping coverage helps load balancing in ways third-generation wireless cannot.

Extricom's product debuted in late 2005 and is now in its third firmware generation.

David Confalonieri, vice president of marketing with Extricom, said the company's strategy is to approach wireless deployment problems like radio people and not like network people. In practice, that means looking at the coordination of wireless signals rather than their exact physical positioning and blanketing an area rather than precisely mapping circles of connectivity.

"The whole idea behind it comes from a different way of thinking about solving the Achilles' heel of wireless LAN," Confalonieri said.

Extricom's first customers, he said, were often those seeking to solve a specific, tough-to-crack problem: a city council that wanted to outfit its stone-walled chambers with Wi-Fi; a hospital using Citrix that demanded no loss of connection as gurneys were wheeled about.

"I don't think they saw what we were doing as radical," he said. "They saw it as a breath of fresh air, as innovation."

King said that both companies have solid offerings, with no clear winner between them.

"Neither one of them has a clear upper hand technology-wise," he said. "Extricom happens at a much lower part of the stack, while Meru has questions about processor power and ability to run over Power over Ethernet."

King also said that many enterprises might simply stick with what they know. He said there were few problems that third-generation products could not solve and that problems with Wi-Fi phones dropping calls while passing between APs - a problem that both Meru and Extricom claim to have solved - is often not that big an issue for users.

In the long run, King said, the market is big enough to support both companies, although one of them might become a ripe Cisco acquisition target down the road if its technological strengths become a must-have in the enterprise.

The original version of this article can be read online at SearchNetworking.com.

Andrew R Hickey
CMP Channel
February 19, 2008

Wireless LAN vendor Extricom is looking to give VARs more wireless options with the launch of its new PartnerAdvantage Program.

David Confalonieri, the Israel-based vendor's marketing vice president, said Tuesday the new program comes at a time when VARs and solution providers of varying sizes are seeking out differentiated and alternative solutions that will help them take advantage of the booming multi-billion dollar WLAN market.

The new three-tiered program will replace Extricom's existing channel program, which Confalonieri dubbed "generation one," adding that the former program wasn't adequate to scale and keep pace with the direction of the wireless market.

"Our mission is to grow our channel; to grow it moderately," he said. "We're not looking for massive numbers of partners. We're seeking the businesses across the world that are looking to grow their wireless businesses."

Extricom makes enterprise-grade WLAN solutions designed to simplify Wi-Fi deployments. Using a blanket architecture which allows each Wi-Fi channel to be used on every access point, Extricom can create environments with low-latency handoffs and cut down interference.

Extricom offers WLAN infrastructure systems for converged voice, data, video and RFID services, growing markets in which solution providers need to offer products to support those applications while not restricting performance, resiliency and scalability.

Confalonieri said the PartnerAdvantage program is based on driving revenue growth and profitability for Extricom partners by creating a strong sales and marketing bond between partners and the vendor. Extricom will offer partners common-sense, value-adding programs for sales enablement, co-marketing, promotion and investment protection. Confalonieri said the program strives to give partners above average product margins while helping them develop their WLAN expertise, market solutions and protect their pre-sale time commitment through deal registration.

PartnerAdvantage offers three tiers, Registered, Select and Premier. Confalonieri said partners can leverage Extricom's simplicity, total mobility, guaranteed performance and convergence. Additionally, a new partner portal gives resellers access to sales tools and information, education and training, along with pre-sales help and deal development. The program also offers marketing materials and packages that can be customized by the resellers for their targeted customers.

"Streamlining their business is a key initiative here," he said.

He added that along with backend rebates and product margins, VARs who offer services around Extricom WLAN products will also be able to boost revenue. In the U.S., Extricom already boasts nearly 50 partners. There are 25 more partners in the UK and several more scattered throughout to globe.

Confalonieri said the program is straightforward and pragmatic, and highlights "what needs to be done to ensure our partners can expand revenues and expand revenues profitably."

Confalonieri said partnering with a pure-play wireless vendor, as opposed to a vendor that ties together wired and wireless offerings gives VARs a level of expertise in the market that customers will trust.

"That's a game that has to change," he said. "Businesses are demanding more out of their next generation wireless LANs."

Frank Kobuszewski, vice president of technology solutions at Syracuse, NY-based solution provider CXtec, said the Extricom's launch of its new partner program will bring added value to his business.

"We look at Extricom as a company that provides value on multiple levels," Kobuszewski said. "It's a technical solution that will give us an edge in a highly competitive Wi-Fi marketplace, and at the same time we see the value selling relationship enabled by PartnerAdvantage. This will make it possible for us to quickly identify opportunities, close business and execute on our commitments."

In a statement, Dan Kirtchuk, Extricom's executive vice president of global sales, said the PartnerAdvantage Program will be a massive initiative for the 100 percent channel focused vendor this year and in the future.

"Extricom PartnerAdvantage is a key building block in our strategy for 2008 and beyond," he said. "Increasingly, resellers and VARs are recognizing the unique blend of wireless innovation, performance and ease-of-sue that the Extricom WLAN brings to Wi-Fi implementation, and they are evangelizing these value points to the end-user IT community. PartnerAdvantage will enable them to maximize their selling opportunities in a rapidly expanding market."

The original version of this article can be read online in the February edition of ChannelWeb Network .  

Communications News
November 2007

The advent of dual-mode phones that can switch from the cellular network to the WLAN (also called fixed-mobile convergence) is expected to make voice-over-WLAN (VoWLAN) the norm in enterprise environments, as employees become more mobile, often communicating and accessing data from a single device. The success of VoWLAN, however, will depend on overcoming challenges that did not exist in the pre-voice Wi-Fi era.

Many of these challenges are related to the traditional cell-planned architecture of wireless systems, in which each access point transmits on one of the three non-overlapping channels available in the 802.11b/g standard, and in which access points are carefully positioned and "tuned" during the deployment process to mitigate the co-channel interference that can kill transmissions.

Enterprise-class systems are either optimized for coverage (wireless signal is available everywhere in the enterprise, but not with optimal bandwidth) or capacity (a maximum number of users can have optimal bandwidth, but not everywhere in the enterprise), but rarely for both at the same time. In the end, the systems do not address the real challenges of VoWLAN-that voice communications demand mobility and a reliable wireless connection, and voice drives convergence.

No matter what the topology, the interplay between a standard originally developed for asynchronous data transmission and voice technology that depends on regular, synchronous communication will always have some degree of complexity. Users should bear in mind a few facts about Wi-Fi that can be primary determinants of success or failure in a VoWLAN deployment.

Wireless does not always mean mobile. Voice communications require mobility, meaning continuous communications while traveling between point A and point B. This may seem like a trivial detail until realizing that the 802.11 Wi-Fi is, by definition, designed for portability, meaning communications between points A and B are not continuous. This, combined with traditional WLAN systems that organize access points in a cellular pattern, yields networks that are not optimized for mobility. The basic problem revolves around the "handoff," which is what happens as users move through cell-planned WLANs, losing the link from one AP and associating to another as they move. The delay introduced by handoff is usually not a problem for data transmissions but is often a deal-breaker for voice calls.

Mileage will vary. Another voice reality is its need for a constant, stable connection rate. In traditional WLANs, the negative impact of such things as rate adaptation, edge users, coverage holes and interference are not as strongly felt, since data communication, bursty by nature, can tolerate the widely varying data transmission rates that result from these effects. Voice performance, however, will suffer in such an environment, but the cell-based WLAN has no solution to this challenge.

Voice and data do not mix well. Convergence means adding voice to data-but these two traffic types clash. WLANs have been data-centric and, even with the advent of new standards, still have inefficient quality-of-service (QoS) mechanisms for prioritizing voice over data traffic. Effective QoS needs to be based on deterministic methods, otherwise the co-existence between converged voice and data will be uneasy at best and unworkable at worst.

An alternative approach to cell-based systems has been to allow all access points (APs) in the network to transmit and receive on the same channel, creating a "channel blanket" from the aggregate coverage of the APs.

The channel blanket eliminates the problems associated with supporting the mobile user, particularly the issues of handoff, reliable and stable connections, and QoS. The ease of deployment and maintenance of such systems, compared to more complex cell-based topologies, is an additional benefit of this architecture, since the RF cell planning of traditional systems is eliminated.

David Confalonieri is vice president, marketing, for Extricom, New York.

The original version of this article can be read online in the November 2007 edition of Communications News . 

Dave Bailey
IT Week
30 October 2007

The last time I tried to connect to a large wireless network that was supposed to cater for a large number of people was at the 2006 GSM conference. After a fair few tries at connecting, I had to resort to the old wired network. Wi-Fi networks should be able to handle the kind of heavy workloads you get at a major trade show. But can they?

That was a question put to me by a company formed five years ago called Extricom. One of Extricom's head honchos, an ex-Motorola radio frequency (RF) engineer, said that the IEEE 802.11 wireless standard was devised for a scenario where a single wireless access point (AP) has multiple clients connecting to it. Would an IEEE body composed of radio-frequency engineers have let the 802.11 standard through? Extricom thinks not.

The 802.11 standard works for households because they typically have only one AP or wireless router, but it struggles when it comes to enterprise deployments featuring multiple APs across large campuses. Add the need to cater for mobility, and current systems really do begin to creak.

For me the term mobility conjures up images of employees wandering around the office with dual-mode handsets, unconcerned about where the best signal is to be had. In this scenario, moving out of range of one AP and into range of another, triggers a seamless signal transfer. Seamless to me means that you can't detect whether there was ever a handoff at all, and you can continue talking, oblivious to what the technology is doing in the background.

At the 2006 GSM show, however, I was shown such a handoff using a dual-mode phone and seamless it wasn't. It was three seconds before I could speak again. Extricom believes it has the technology to get around 802.11's mobility shortcomings.

Its system gives "blanket" coverage on a single channel, rather than the multiple ones used by other vendors, and its "APs" consist of a radio receiver and transmitter that connect back to a central controller. Other vendors use APs as discrete units, whereas Extricom uses its devices to create a "wireless continuum", where you associate to the network rather than to a specific AP. This approach has the potential to make mobility over large areas far less problematic as no handoffs are required. An added bonus is that the technology does away with the need for admins to carry out all those tiresome wireless network site surveys, which are essential when deploying other vendors' kit.

Extricom has recently signed an agreement with BT, which means this small, independent company could make some big household names vulnerable to being on the wrong end of a handoff themselves.

The original version of this article can be found in ITWeek Magazine. It can be accessed by clicking here . 

Fahmida Y. Rashid
CMP Channel
October 29, 2007 

There are many reasons to "cut the cord" on the local network, among them supporting mobile employees and simplifying network setup and maintenance. There are also reasons to stay plugged: performance and reliability. The WLAN enterprise solution from Israeli-based Extricom can ease those concerns, and let businesses use wireless technology more effectively.

The role of business WLANs is changing: Businesses are shifting the entire corporate network to a WLAN to cover large areas and connect remote offices. Increased reliance on WLAN means handoff latency and weak signals are no longer acceptable when the network is carrying video and voice applications.

Extricom wants to enable triple-play and other services, such as voice, data, and video on a WLAN. To successfully support those applications, the WLAN's performance and resiliency must increase, but also remain affordable and easy to maintain. Extricom's wireless solution achieves that with a switch that puts all the access points on the same channel, using the same frequency.

The product uses all available Wi-Fi radio channels on every access point to create a continuous blanket of coverage. Within each blanket, there is seamless mobility with no handoff latency, no co-channel interference and robust connections similar to those in a wired network.

Separate channel blankets can also physically segregate different user types, traffic type and roles onto different channels to improve quality of service. A multilayer WLAN consists of multiple channel blankets. With two or more channel blankets operating on channels in the same band, users can simultaneously have a phone call on one channel and streaming video on another channel. Moving around doesn't drop the phone call or streaming video, and there is no fighting for bandwidth between applications.

Having all the access points on the same radio channel and the same frequency prevents interference because the switch decides on the packet level which access point a client should be connected to at that moment. Once a client is connected to the WLAN, it never hands off to a different channel. When the user moves within a different access point's range, the switch diverts the client's data connection to that new access point. The transfer is seamless; the client device does not encounter any lag time as the new access point kicks in. A software application has a screen display that shows which client devices are connected to which access points and indicates the transfer as it happens.

Extricom Interference-Free EXWO-404 WLAN Switch works only with a company's own access points. Because the UltraThin devices contain no software or storage, they are managed centrally by the switch. It handles centralized packet-by-packet processing and decides which access point to use based on real-time conditions whenever a packet is sent. The switch has a complete radio map of the network-which lets the switch know which access points are transmitting data and where the data are, allowing it to assess when and where to transmit, and through which point.

Conventional WLAN systems require extensive site surveys and cell planning so that access points are placed to meet radio frequency requirements. Because Extricom uses channel blankets, there are no cell points to consider.

The EXWO-404 Wireless Office system is an all-in-one package consisting of a WLAN Switch and four UltraThin Dual Radio Access Points. Priced at about $4,320, the system is designed for small networks, such as those found in a branch office or any other environment with limited coverage.

The original version of this article can be accessed in the October 29, 2007 issue of CRN by clicking here .

Peter Judge, Techworld

October 24, 2007

Cell-planning is the Original Sin of Wi-Fi according to Gideon Rottem, chief executive of Extricom, a company dedicated to preaching a different gospel.

"The sin at the base of Wi-Fi networks is to use the scarce resource of spectrum to increase coverage," he says. In his view, Extricom is there to remove that sin.

Wireless LAN switches, from Trapeze, Motorola/Symbol, Aruba, Cisco and others, use a set of wireless LAN access points to cover a building. Each AP has to be on a different channel to its neighbour - and in the 2.4GHz spectrum used by 802.11b and 802.11g, there are only three non-overlapping channels. The best way to fill a large building with Wi-Fi is a hexagonal array of APs, and that sets up points where three APs' coverage overlaps.

So you can do wireless LANs in 2.4GHz, and that's what those vendors have been doing now, for up to five years in some cases. But now 5GHz is opening up, some of them admit it's been a struggle. "The fact remains that there is simply not enough spectrum available in 2.4Ghz space to ensure a quality service," said Pat Calhoun, CTO of Cisco's wireless business unit, in his blog. "...no matter how creative your channel plan is, any deployment that exceeds three APs will see some co-channel interference - including from devices that may not be under your control (is your neighbor running a network?)."

But Rottem reckons it's been wasted effort. It's better to put all the access points on the same channel, and use processing power to sort data packets and send them to the right access point to reach the client. That's the basis of Extricom's "channel blanket" approach, which we've covered here pretty often .

Just like all the other wireless switch sellers, Rottem reckons that 2008 will mark a major take-off of Wi-Fi, with the arrival of 802.11n, and dual-mode Wi-Fi handsets. He calls it an inflection point, when users will snap up wireless, to run voice, and support multiple applications.

His claim is that, with or without 802.11n, the other architectures can't deliver. They can't do mobility, because they hand-off too slowly between access points, and they can't deliver quality, because of co-channel interference, he believes.

It's a familiar Extricom story, but Rottem comes down pretty hard on rivals - especially Cisco. He visited Cisco to pitch the Extricom vision, shortly before Cisco bought into the cell-planning model, with Airespace in 2004. "I went to show we could do less than 50ms handover," says Rottem. That's what Cisco claimed it could achieve with its standalone Aironet access points, he says: "Dave Leonard [then Cisco's wireless chief] asked 'Why 50ms? Marketing does 50ms, we do 150ms'."

So if even Cisco says 2.4GHz isn't good enough, will 5GHz help? It has a lower penetration than 2.4GHz, says Rottem, and cells have to be smaller. The MIMO element of 802.11n will increase this, but it will be unpredictable, and that might make cell-planning a nightmare.

And 5GHz 802.11n won't have as many channels as it's cracked up to have, he says. Cisco's N access points may only do three non-overlapping channels in the 5GHz band, he believes. That's a conversation stopper for me, because till now, I haven't got past the usual assertion, repeated in Cisco's Aironet 1250 data sheet that the 5GHz band has "up to 24" non-overlapping channels.

Look more closely says Rottem. Use 40MHz channels, and take international regulations into account, and the number goes down. There's a footnote on the Cisco datasheet, that suggests there may only be nine non-overlapping channels in the US, and Extricom has seen Gartner advice that suggests only three channels in the end, he says.

"It's an interesting issue that I'm following up. Wherever we get to with that, 802.11n falls down because it focuses on range and speed," says Rottem, and will be dragged down to poorer performance by the presence of b and g clients. "The promise of MIMO is stability for a single client, but we have multiple clients."

Blankets, by contrast, allow an enterprise-grade N network, even on 2.4GHz, since they can have one 40MHz channel for N and a 20MHz channel for b and g - a scheme which would, I suggest might be just as vulnerable as a cell-planning system, to interference from neighbours' Wi-Fi - though Extricom argues that its architecture offers more resilience because signals can be sent and received form any AP.

But is there a different agenda here, I ask? Is Rottem downplaying 802.11n, simply because it's going to be tricky to implement it on a blanket system? To build a blanket, Extricom has taken the MAC layer off the access point, and re-implemented a central MAC on the switch for all access points. They still have a lot of WLAN smarts (they're not a distributed antenna system) but they all have the same MAC address. "We're actually a MIMO-like array, but at the network level," says Rottem's colleague, marketing VP David Confalonieri.

"The reason we put the MAC at the centre is because it is much better," says Rottem."Anyone who says don't do it, just can't. That's why they say it."

But other vendors can pick up N chipsets from Atheros as they are, while Extricom has to re-write the MAC to put it centrally. That causes a delay, but not much of one, says Rottem. He's determined to ride the wave of N hype that is coming, and that means he's going to at least announce N sometime this year.

"We're going to do it," he says. "We are going to have the best N network in the world. Cisco can have an N access point - we'll have an N network."

The original online version of this story is available on the TechWorld website.

Rik Turner
Computer Business Review

The significance of this announcement is twofold. First, BT iNET has until now offered only Cisco WLAN kit, so the fact that it now has a second option suggests that, at least for some customer requirements, it feels the need to have an alternative.

Second, Extricom is not just another WLAN vendor. It is one of the main proponents of a different approach to the cell-based architectures that have dominated until now, in which interference between neighboring APs is avoided by deploying them on different channels. Extricom and Meru, on the other hand, advocate a coverage blanket, in which all the APs on the same channel and each has the intelligence to determine which one will handle traffic at a given moment. They tout this way of deploying the APs as better for VoWiFi, in that there is no issue of handover between them.

Herzlia, Israel-based Extricom calls its offering Interference-Free Enterprise Wireless LAN to underscore this different architectural approach. David Confalonieri, the company's VP of corporate marketing, said the rapprochement with iNET came as a result of a particular project for an educational institution in the UK called Bishop's Stortford College, where the SI is deploying Extricom equipment to cover a 130-acre campus for voice, data, and video traffic.

"The way iNET works is that they buy from distributors, and they went to a UK partner of ours called Selcoms, who recommended our technology, from which the relationship has developed," he said. One of the challenges of the project was that "the college has a number of Harry Potter-ish old buildings in an environment where it is difficult to lay out a cell-style WLAN."

He said Extricom has now worked on a number of other projects with BT and they are not all in the education market. "They came to us for the capacity we could deliver, as well as the lower ongoing maintenance cost of our infrastructure, after which they have also come to appreciate the mobility and security we can offer," he said.

Our View

BTGS is a very close partner with Cisco and does a lot of business with the networking heavyweight, be it in IP telephony or LAN infrastructure, so the fact that it now has a second source for WLAN, and that the source in question offers the coverage blanket mode of deployment is an important new development.

For Extricom, a partnership with BT iNET is a huge endorsement of its technology, so it will be interesting to see whether the two strike a lot of deals together, and whether any of the customers are in the mainstream enterprise sector. It will also be interesting to see how widely the BT division offers the technology, and whether it starts promoting Extricom in other geographies outside the UK.

The original online version of this article can be viewed at the Computer Business Review website. 

Peter Judge
Techworld

Pupils at Bishop's Stortford College, Hertfordshire, have wireless access to the Internet across the campus and in their dormitory buildings, thanks to a system from Extricom.

We visited the school to have a look, largely because we have been following Extricom for a while, intrigued by its novel approach to Wi-Fi switching. This was our first chance to see the product in action.
A learning experience

The college is an independent school for pupils aged four to eighteen years, some 220 of whom board in the college while others come in as day pupils. The College's many buildings, set in 130 acres, lie on either side of a residential road.

The college has a fibre network in its central buildings, using Extreme switches to cover the teaching and learning areas. A wireless network covered most teaching areas but when laptop users started to want greater coverage of the wireless connectivity, the IT department saw the opportunity to take the network to other buildings on the site - to give laptop users access in their residential areas.

"There was demand from the pupils and parents for pupils to have Internet access in the houses where they live," says IT head Steve Bacon. The children wanted to use it for study out of hours and for keeping in touch with their families. "It seemed appropriate, and they have handled it very maturely."

Rather than link the buildings with wire or fibre (which would be difficult across the residential road), the college decided to use a wireless link between the buildings, and then distribute it wirelessly within the buildings.

The school put an Alvarion BreezeMax (pre-WiMax) network, running on 5.8GHz, between the buildings, using a transmitter in the school's clock tower. The school operates two separate VLANs, one for students and a secure encrypted network for staff. Both of these were extended to the school's houses over the Alvarion link.

Bacon spoke to BT iNet, who suggested Extricom switches would be a manageable way to distribute signals by Wi-Fi within the houses, since they use a "blanket" architecture where all access points are on the same RF channel. This eliminated the manual RF management which Bacon had found in the Proxim access points he had been using to unwire the colleges central buildings.

Inside each house, there is a wireless channel for the students, and a secure encrypted wireless LAN for staff, as well as a single fixed staff PC.

The buildings were a test of wireless penetration: "It's straight out of Hogwarts," says Bacon. "We have every kind of wall and floor." Despite this, the network was put in within two weeks. The only cabling in the houses was between the Alvarion receiver and the Extricom switch, and then to the access points - which are powered over Ethernet to make installation simpler.

These switches could be managed over a separate VLAN, but in the six months or so they have been running, Bacon hasn't needed to set one up: "They run unattended," he says.

In future, Bacon is considering an option to add voice to the network on a second "blanket" channel. The school currently uses a hosted Centrex solution instead of a PBX, but could replace this with an in-house IP PBX. Another option is to add wireless CCTV cameras to the college's existing hard-wired ones.

We visited the College and saw inside Robert Pearce House, where around thirty students live. The building is covered by eight access points. Although the building had no integral cable conduits, it did have suspended ceilings which made wiring the APs in easier.
A voice demo

Although voice isn't yet in widespread use, we had a demonstration of the voice-roaming ability of the Extricom switch. We carried out a conversation over Wi-Fi phones, while walking within the house. There was no noticeable lag or gap when moving from one access point to another - a management utility showed our signal moving from AP to AP.

Whether or not voice is implemented on the network, Bacon is happy with what he has: "It's scalable - it just works."

The original online version of this article can be viewed at the Techworld.com website

Peter Judge
Techworld

BT is reselling a "blanket" wireless switch from Extricom, which covers a building using adjacent access points on the same Wi-Fi channel.

BT iNet, a division of BT Global Services created last year, has sold several systems already, including one at Bishop's Stortford College in Hertfordshire, where Extricom systems have been put in residence halls within the College's 130-acre campus to give students Internet access in their dorms as well as in the IT classrooms (read Techworld's case study ).

Extricom's system is designed for seamless mobility, because there is no handoff between access points, it's also easy to deploy, according to Stephen Bacon, head of information technology at the College, who says it has needed little or no management since being put in last year. A single-channel blanket means no "cell-planning" is required to avoid co-channel interference when access points are installed in a building.

iNet has been working with Extricom for some time. It installed the Bishop's Stortford network last year, and has had a case study on its site for months.

Despite this, iNet has taken a long while to make the announcement - a delay which may be bureaucratic, or may be connected to the fact that iNet is a Cisco gold partner, selling Cisco's rival wireless LAN, which - like most wireless LAN systems - uses cell planning. The Extricom system has reportedly been easier to install, but iNet is still working with both.

The Extricom system will come into its own as voice and location applications become more important, according to Steve Northedge, vice president of EMEA sales there. "Voice and location applications demand mobility, and this is the first system to bring total and seamless mobility to Wi-Fi, while also enhancing all other facets of performance such as coverage, capacity, and security."

Despite positioning itself as forward-thinking, Extricom has warned users not to adopt 802.11n fast Wi-Fi technology before it is standardised.

The original online version of this article can be viewed at the Techworld.com website. 

Teresa von Fuchs
Mobile Enterprise Magazine

We're suggesting says David Confalonieri, VP of corporate marketing at Extricom, an enterprise WLAN company with a new vision of pervasive wireless, "that we can deploy WLANs as simply as you'd deploy wired access."

At first this doesn't sound like a radical idea-WiFi is old news-but the difficulties surrounding an enterprise WLAN deployment can extend well beyond the reasonable. Installing a pervasive wireless network in any market, from warehousing to education to office buildings, requires delicate planning with multiple stages of preparation. RF interference mapping and cell planning can take months, and then once the network is deployed, more time is needed to work out any bugs. In many environments interference issues, such as competing signals or even physical barriers, can shift and change from day to day, forcing IT staff to constantly maintain and tweak the system. Confalonieri likes to cite an instance where an enterprise had to hire three extra people just to manage 150 newly installed access points. Not a very compelling business case.

Problems notwithstanding, the march toward pervasive wireless deployments isn't slowing down. Craig Mathias, principal of the Farpoint Group, an advisory firm specializing in wireless and mobile, says he hasn't published research on WLANs in two years because, as he sees it, "WLANs are becoming default connectivity for the enterprise. There's no point in arguing about the numbers." And it's true, WiFi has revolutionized the way we work; as more people are freed from their desks, the demand grows for an always-connected environment. "We use the same technology at home, at work, on the streets, even internationally," says Mathias. "That's huge. There's no technology that will replace WiFi."

So while the course is set for WiFi, Extricom felt the issues around ease of use and deployment needed addressing. "Extricom was founded on the premise that when you take WLAN into a network environment you run into major technological difficulties," explains Gideon Rottem, Extricom's co-founder and CEO. "These limitations are so evident," continues Rottem, "we've had to create a language around them. We hear so much talk about black holes and that wireless is black magic."

Extricom has worked for the last five years in an effort to put some reliability into the magic of WiFi. Extricom's system differs from traditional WLAN architectures in that its access points are trimmed down to just the basic radio, and it has added a beefed-up central control switch that's responsible for every packet sent over the network. The packet controller automatically adjusts to interference issues across the network ensuring that packets are never dropped, lost or delayed.

Extricom maintains that this eliminates a common WLAN complaint, the need for frequent maintenance and retooling to eliminate holes in coverage and to maximize users' throughput speeds. With the packet-by-packet controller ensuring every bit of data ends up where it was intended, Extricom claims to have added a guarantee to enterprise wireless. "Our solution allows us to eliminate co-channel interference within the blanket [network]," claims Rottem. "The minute you eliminate co-channel interference between those access points, you've allowed the evolution of a true channel blanket technology."

Eliminating interference issues certainly eases the complications of deployment. "One of our customers is a hotel with 10 floors and about 200 rooms, in total about 300,000 square feet," says Confalonieri. "We plugged in the APs, plugged in the switch and basically had the whole deployment up in six hours." No RF mapping, no complicated cell planning, once the wires are in place, just plug it in, says Confalonieri, and it's up and running. As Mathias puts it, "No one gets up in the morning and says, ‘I'm going to buy an architecture today.' They will get up in the morning and buy a solution." Extricom wants its WLAN to be an obvious choice.

It certainly was for the New York Software Industry Alliance (NYSIA), a trade association based in Manhattan, with a facility that is the nurturing home to numerous up-and-coming high-tech companies. With tenant companies that have rapidly fluctuating personnel and differing, specific connectivity needs, the NYSIA knew it had to unwire its 22,000 square feet of office space. But without a permanent IT staff, it couldn't see a way to manage a flexible WLAN installation and was going to settle for just guest access. Until it found Extricom. In two business days, Extricom had the first phase of the deployment, one floor and most of the conference rooms up and running. With phase one turning out to be such a success, the NYSIA went ahead and unwired the rest of the space and included a total rollout of VoWLAN phones to each tenant company. The solution has been in place for 18 months and has required almost no maintenance from IT, while providing uninterrupted, flexible, truly mobile wireless access to more than a dozen tenant companies in a space that is frequently changing.

All In the Apps

Making WLAN solutions more reliable, in turn makes them more useable, because how we use wireless is more important than its mere existence. "The business case [for wireless]," agrees Confalonieri, "is really in the applications." Extricom claims this is another area where its solution provides better functionality than traditional WLAN offerings.

"The problem with Cisco-type deployments is that they're using the radio for coverage," explains Rottem. "Whereas Extricom, by providing multiple blanket coverage everywhere, allows a much thicker use of applications. You can have one channel for multiple data uses, one channel for voice and another for video." This allows organizations such as the NYSIA to transition over to VoWLAN without the worry of calls being dropped or unreliable service.

Some applications further stretch the boundaries of wireless. Confalonieri offers the example of a company in Germany working on the latest roller coasters, whose cars reach speeds of up to 125 km/h. The company needed a way to control the fail-safe system on the brakes. "Here's an example of truly seamless mobility," explains Confalonieri. "Within our channel system there is no handoff and no overlay, so you have a continuity of the session. In the case of the roller coaster, as the car speeds down the track it is in constant communication with all of our APs mounted along the track." This constant communication ensures the coaster is working properly. If communication is lost for more than 300 milliseconds, the fail-safe triggers the emergency brakes. "This situation could only be solved by our technology," asserts Confalonieri.

Then there is the example of the airport that wanted to install closed-circuit TV cameras in the tramcars that connect the terminals. With a typical WLAN deployment, the airport security team found that when the connection was handed off from one AP to another, they'd wind up with 20 seconds of blank frames. "A delay in the handoff is not acceptable," emphasizes Confalonieri, "when you're talking about security measures in airports."

When pervasive, reliable networks become possible, the possible applications become very exciting. "There's all kinds of uses that are popping up like this to prove that the key driver is mobility," asserts Confalonieri. "WiFi has traditionally been designed for portability; you're stationary when you're working, then you close your laptop and go to the next hotspot. But more and more customers are saying we need mobility for voice, for situations like the roller coaster or RFID applications."

The new and diverse uses of these networks will keep businesses talking for the next 20 years, and Extricom wants to be a part of that conversation. "Extricom wants to say that wireless is no longer [about giving your] best effort," says Rottem, "but that wireless is guaranteed." And since wireless is guaranteed to be in our future, a usability guarantee will be a good thing to offer.

Teresa von Fuchs is a freelance writer living deep in the heart of Texas.

The original online version of this article can be found on the Mobile Enterprise Magazine website.

Elena Malykhina
InformationWeek
March 3, 2007

The wireless local area network equipment market isn't a place you'd expect to see startups with high hopes of snatching business away from Cisco Systems or the other market leaders. But as more companies get serious about installing wireless LANs, this growing market appears to have plenty of opportunities, especially for new ideas.

Businesses initially deployed WLANs for occasional use – say, to give workers network access in conference rooms and to let guests and other transients have Internet access on company premises. More recently, they've become networks of choice for some businesses, often covering large areas and connecting branch offices. Sixty-three percent of U.S. companies use in-house WLANs to provide access to applications, according to a Forrester Research survey a year ago. They face the challenge of finding the right equipment vendor with a system that can handle the load, as well as offer strong security and reliability. Cisco holds 66% of the market, Gartner says, but it's a market growing fast enough to leave opportunity for startups.

One, Extricom, focuses on enabling multiple services over WLANs, including voice, data, location-based services, and video. Extricom rolled out its WLAN system two years ago, claiming to have an architecture in which every access point uses all the available Wi-Fi radio channels to create a continuous blanket of coverage. These multiradio access points increase capacity and eliminate interference, VP of marketing David Confalonieri says.

Conventional WLAN systems require extensive site surveys and cell planning so that access points can be carefully placed to meet radio frequency requirements. Another component of Extricom's system is "ultrathin" access points that contain no software or other intelligence, designed to make it easier to centrally manage them from a wireless switch.

Success Strategy

The WLAN startups are making relatively small market share inroads, though gaining some big-name customers and niche acceptance. None of them is brand new: Extricom was founded in 2002, the same year as Aruba Networks, Meru Networks, and Trapeze Networks. Aruba now has 7% of the WLAN equipment market, Meru 1.6%, and Trapeze 1.5%, according to Gartner. Extricom's share is even smaller.

Wireless LAN Equipment Vendor Market ShareAruba has snagged significant customers, including Microsoft, from Cisco with its centrally managed WLAN network security and policies. Aruba last week launched several initiatives, partnerships, and new capabilities to help IT managers in health care implement applications, such as patient monitoring and workflow management, on a single wireless network.

Trapeze also is trying to differentiate itself with equipment designed for services in high demand, such as location and asset tracking. Trapeze last week started shipping its LA-200 Location Appliance, a device that can be plugged into Trapeze's WLAN system to provide instant location information of all Wi-Fi-enabled devices on the network.

Similar location information is provided by Cisco and Hewlett-Packard's joint pervasive WLAN effort--wireless networks that encompass buildings as opposed to separate departments or conference rooms within a building. Pervasive WLANs can be used to spot a Wi-Fi-enabled device for locating workers inside a building or radio frequency identification tags on assets. Other potential applications and services include security, guest access, and voice over Wi-Fi.

WLANs originally were designed for data-centric applications. Now Cisco and other vendors want to design voice-enabled systems that let people make and receive phone calls over internal networks and avoid cellular charges. "Customers say that no longer is wireless about access and transport, but instead they see it as a platform for mobility services, such as voice," says Maciej Kranz, VP of marketing at Cisco's Wireless Networking business unit.

Some startups also are looking at this broader approach as a way to enter the WLAN market. Aerohive Networks says it's building a new class of enterprise WLAN products that will offer management, security, and mobility, and will eliminate network integration challenges.

It's clear no one vendor has the market figured out. "The whole WLAN space is ripe with innovation," says Craig Mathias, an analyst at Farpoint Group. "It's a good time for new companies to come in." All enterprise-class systems offer much the same functionality, with some architectural differences distinguishing them. But startups still have a fair shot if they can get away from selling access points and switches for basic Internet access.

CHICAGO, November 2, 2006 - Mobile Business Expo, produced by CMP Technology, today announced the winners of the first annual MBX Ultimate Mobility Awards, sponsored by InformationWeek. The MBX Ultimate Mobility Awards highlighted case studies featuring mobile and wireless deployments in extreme conditions or unique circumstances, and submissions were open to industry vendors. During a presentation today at Mobile Business Expo, first place was awarded to TTL Network, using technology developed by Extricom; second place went to SurgiCount Medical for a device created by Hand Held Products; and Trican Well Service took third place for their use of NetMotion Wireless technology. Mobile Business Expo (http://www.mobilebusinessexpo.com/) will continue to take place at the Hyatt Regency Chicago through Friday, November 3.

"As mobile and wireless technologies continue to improve, enterprises are finding creative new ways to generate ROI and increase business productivity from their enterprise deployments," said Rob Preston, Editor-in-chief, InformationWeek. "We recognize these winners of the MBX Ultimate Mobility Awards for showcasing prime examples of how companies are utilizing mobile technologies to improve business productivity and increase ROI."

Additional details on the winners of the MBX Ultimate Mobility Awards are

First Place: TTL Network, using technology developed by Extricom

TTL Network, an innovative systems integrator based in Germany, has conceived and implemented a truly unique application of wireless LAN, to wirelessly control the braking system of a new breed of rollercoaster. TTL selected the Extricom WLAN system, as they found it to be the only solution that can enable the seamless mobility needed to guarantee that the car maintains uninterrupted communications with the track, even as the coaster travels at an unprecedented 125 km per hour. With the Extricom technology, the car (i.e. the Wi-Fi client) remains on the same channel throughout the entire ride, and communicates with a series of access points mounted along the length of the track. The communications link is reliable, constant, and available, something that is physically not possible with a traditional cell-based WLAN topology.

Second Place: SurgiCount Medical, using technology developed by Hand Held Products

Gossypiboma is the medical term associated with leaving a surgical sponge inside the human body after surgery, estimated to occur 3,000 - 5,000 times every year, costing Americans about $750 million to $1 billion annually. Dr. Atul Gawande, a medical researcher at Harvard Medical School's Brigham and Women's Hospital, uncovered some startling statistics through an isolated study of medical injury in 28 Utah and Colorado area hospitals:

• Two-thirds of adverse events resulting in death, disability or a prolonged hospital stay were due to surgery
• 3% of surgical patients experienced a medical injury
• These injuries contributed to 12.2% of all hospital deaths

Further research revealed that a simple step in improving surgical safety would be to ensure that surgical sponges used during surgery were properly recorded and discarded post-operation. Dr. Gawande's team and Hand Held Products partner SurgiCount Medical devised a way to attach surgery-grade 2D bar codes onto the surgical sponges used in the operating room as a way to keep track of all materials used during surgery. In March 2006, the FDA approved the first computer-assisted program to count surgical sponges, called the Safety-Sponge System, developed by SurgiCount Medical, using mobile computers from Hand Held Products.

Third Place: Trican Well Service, using technology developed by NetMotion Wireless

Trican Well Service provides equipment and services for the drilling, completion and reworking of oil and gas wells. Its field service technicians deliver cementing and fracturing, deep-coiled tubing and nitrogen services to wells spread across hundreds of miles of the most remote areas of western Canada. Trican's technicians needed a way to access it and other applications from the field, and a new mobile infrastructure with satellite, 1X and EVDO was created and 300 rugged laptops were deployed with Mobility XE, a mobile VPN software solution from NetMotion Wireless. Inter-network roaming in the VPN lets techs securely traverse wireless networks throughout the day without multiple logins, and even in areas without network coverage, persistence maintains their application sessions without data loss or repeated network and application logins. Aside from improvements in workforce efficiencies and field communications, Trican was able to dramatically reduce their work completion time to payment cycle with Mobility XE.

Mobile Business Expo will feature the business mobility market's leading vendors and industry experts, providing attendees with the latest technology solutions to build a mobile workforce and wirelessly extend existing asset management systems. The event has received support from industry influencers, and the lineup of sponsors and exhibitors includes:

Diamond Sponsor:

• Symbol Technologies

Platinum Sponsors:

• AT&T
• Siemens HiPath Wireless LAN

Gold Sponsors:

• Sybase iAnywhere
• Trapeze Networks

Mobile Business Expo Exhibitors:

• Aruba Networks
• Diagonal Consulting
• Extricom
• FieldWorker
• LANDesk
• Meru Networks
• Microvision
• NetMotion Wireless
• Opticon
• PARAT Solutions
• RangeRoamer
• Sage Software
• SalesNOW
• SmartSynQ
• Smith Micro
• Symantec
• Xirrus, Inc.

Mobile Business Expo also features a 3-day conference that provides the most thorough investigation of the relevant technologies, applications and platforms enabling the mobile enterprise. Through demonstrations and quality education, attendees at Mobile Business Expo will take away the information they need to implement a secure, end-to-end mobile business plan – one that delivers value throughout the organization – including remote worker communication, field force data collection, internal asset management and tracking, customer service applications and sales support.

About Mobile Business Expo

Mobile Business Expo integrates the business strategies, technologies, tools and corporate issues necessary to build an end-to-end mobile strategy and manage a mobile workforce. Mobile Business Expo is targeted towards IT professionals, business managers and channel professionals who are focused on leveraging wireless technologies and looking to integrate the disciplines, technologies and vendors involved in the enterprise mobility equation. Mobile Business Expo will take place at the Hyatt Regency Chicago, October 31 to November 3, 2006. For more information about the event, please visit http://www.mobilebusinessexpo.com/.

About CMP Technology

CMP Technology (http://www.cmp.com/) is a marketing solutions company serving the technology industry. Through its market-leading portfolio of trusted information brands, CMP has earned the confidence of more technology professionals than any other media company. As a result, CMP is the premier provider of access, insight and actionable programs designed to connect sellers and buyers in ways that yield superior return on investment. CMP Technology is a subsidiary of United Business Media (http://www.unitedbusinessmedia.com/), a global provider of news distribution and specialist information services with a market capitalization of more than $3 billion.

Mark Blowers
February 28, 2006

A wireless environment can be difficult to administer with potentially many different types of users, including short-term guests, wireless capacity problems, and security threats. Enterprises also need to take into account the integration of new wireless hardware with existing WLAN infrastructure, including the additional complexity brought about by the use of Access Points (APs) from multiple vendors. To maximise the productivity benefits of a WLAN requires the ability to manage capacity and the deployment of an integrated wireless management solution.

Wireless technology brings into focus system and network security, as physical barriers no longer apply. The ease with which an employee can deploy a rogue wireless access point for personal use also adds to the potential for serious security breaches. Organisations need to be able to quickly detect and isolate rogue devices. This has resulted in wireless networks not being adopted in enterprises as quickly as anticipated. Although, there now seems to be a growing trend for organisations to move from dipping a toe in the water to wireless enabling more office space, including meeting rooms and public areas. Especially as providers of wireless solutions are now addressing the challenges found in the enterprise, as can be seen by two announcements in February, which will be of particular interest to IT managers contemplating getting serious about wireless networks.

Extricom, a designer and manufacturer of high-performance Wireless LAN (WLAN) infrastructure solutions for the enterprise, as unveiled TrueReuse which can provide a three-fold increase in channel capacity. The release, expected in the second quarter of 2006, brings together two complementary approaches: an interference-free channel blanket topology, for achieving reliable coverage and seamless mobility with simple deployment, and real-time frequency reuse inside the channel blanket, for an increase of total capacity.

Kevin McLaughlin, CRN
February 17, 2006

Israel-based startup Extricom is targeting the U.S. market with a WLAN architecture that significantly boosts the capacity and range of wireless networks while eliminating interference.

Extricom, which has offices in New York, last week introduced a 24-port WLAN switch that incorporates a proprietary technology called TrueReuse that triples the capacity of a standard Wi-Fi channel by dynamically managing bandwidth, said David Confalonieri, vice president of corporate marketing at Extricom.

In contrast to other WLAN infrastructure, Extricom's solution consists of hardware and firmware loaded on the chipset inside its switches and access points, and doesn't incorporate software. It's especially suitable for enterprise deployments because switches are designed to allow access points to operate simultaneously on two channels in the same band without causing interference, Confalonieri said. "That's a physical RF challenge that we're able to overcome because the switch is tightly controlling everything the access point does," he said.

This architecture also makes it possible to segregate different types of traffic and users and works well with bandwidth-intensive applications such as VoWLAN and streaming video, he added.

Nate Tyson, president of Venture NetComm, a Lawrenceville, Ga., solution provider, said Extricom's solution is easier to deploy than WLAN gear from other vendors he has worked with. "Extricom provides a great alternative to more complex WLAN solutions because we can go in to the customer and quickly set it up without a lot of preliminary work," he said.

Extricom's WLAN solution can be deployed side-by-side with other vendors' WLAN gear without interference. In addition, Extricom's own access points can overlap without interfering with each other, allowing for tighter, more effective coverage with no dead spots, Tyson said.

Extricom, which received an undisclosed investment from Motorola's venture capital arm last month, has signed up some 50 VARs since entering the market in October, and has a nascent partner program offering volume discounts.

By Ted Stevenson
February 9, 2006

Wi-Fi (wireless LAN) and VoIP are natural partners. In a world that's become totally accustomed to walking while talking, a wireless connection to a company's converged IP voice/data network makes all kinds of sense. And indeed, voice over WLAN aka VoWi-Fi, VoFi, and a few other convoluted acronyms has been available for years. But there have been some barriers to its widespread adoption.

Perhaps foremost has been the absence until very recently of a standards-based solution for prioritizing voice traffic on converged WLANs. Why is this an issue? Because of the limited bandwidth of IEEE 802.11 (Wi-Fi) networks, relative to their wired counterparts. When data packets 'contend' for bandwidth with voice packets, the quality of the voice signal plummets.

Also troublesome is the process of roaming-shifting connections between moving clients (phones or other voice-enabled devices) and stationary Wi-Fi access points (transmitters) because a smooth 'hand-off' is hard to achieve.

New technology being demonstrated today by Wi-Fi infrastructure vendor Extricom, addresses both of these issues, in a way that should make VoWi-Fi a more viable choice for many enterprises. In a dual announcement at Demo 06 , Extricom unveils a new hardware configuration and a new technology concept. Not surprisingly, the two go hand in hand.

The hardware in question is the EXSW-2400 Wireless Switch, a device for centrally managing up to 24 "UltraThin" access points (APs). The technology concept is trademarked TrueReuse. To appreciate the details of these announcements we'll need to step back a pace or two and absorb some background information.

First of all, proprietary switches and the resulting central network management have become firmly established in the Wi-Fi world over the past several years, as they make possible many performance improvements in the basic 802.11 technology. Part and parcel of this trend to centralizing network intelligence in the switch has been a move to "thin" APs-the ultimate extension of which makes the AP simply a radio.

Second, we need to understand a bit of basic 802.11 RF (radio frequency) reality: The radio spectrum used by Wi-Fi occupies defined frequency 'bands,' which are subdivided into a limited number of broadcast 'channels.' In a standard Wi-Fi deployment, adjacent APs using the same channels will interfere with each other-reducing effective bandwidth. With the two most common 'flavors' of Wi-Fi-802.11b and 802.11g-there are only three non-overlapping channels, and the standard approach to 're-using' the channels across a network while minimizing 'co-channel interference' is to stagger channel use in a network of APs in a kind of honeycomb configuration. 'Minimize' is key here, since it's impossible to eliminate co-channel interference this way.

Okay, back to Extricom and the EXSW-2400. While other centralized switch architectures are able to control things like broadcast power for all the network APs-thus controlling interference to a degree -Extricom's new switch actually keeps track of each packet and the location of the AP to which it is being dispatched, and in this way, according to vice president of marketing David Confalonieri, allows the total elimination of interference. "We haven't just mitigated these problems, they simply don't exist" Confalonieri told VoIPplanet.com.

In a nutshell, this packet-by-packet micro-management of multiple data streams means that adjacent APs are never broadcasting at the same time, hence, no interference. At the same time, it extends the coverage for each channel on the network to the entire web of APs, creating what Extracom calls a 'channel blanket.' "Every channel is at every AP," Confalonieri explained. "The capacity of that channel is available everywhere in the network."

But there's more. Extricom's APs carry dual radios, and can thus broadcast all three flavors of Wi-Fi-802.11a, b, and g-sequentially. Among other benefits, this allows IT staff to completely segregate different types of traffic (e.g., voice and data) on different radios, completely eliminating the 'contention' issue or need to prioritize traffic.

Furthermore, the switch is smart enough to know which APs are far enough apart so that simultaneous transmission on a given channel simply won't produce any interference. "Imagine that there's a radio station broadcasting at a particular frequency in New York City," Confalonieri said. "If you had a station broadcasting on the same frequency across the river in New Jersey, it might interfere. But you could have a station in Boston reusing this frequency. It's far enough away." This is really the basis for TrueReuse, as it allows simultaneous transmission on the same channel by widely separated APs, multiplying the effective bandwidth of the network by a factor of two to three..

The technical hurdle to roaming-moving around within a network while carrying on an uninterrupted phone conversation-is how to move a connection (or 'association' in Wi-Fi jargon) from one AP to another without a noticeable hiccup or break in the audio link. This is a 'user experience' issue stemming from our expectations of acceptable phone quality-based on traditional wired telephony.

Extricom's switch solves this 'latency' problem by eliminating the distinction between APs. Rather than associating with a sequence of APs, a mobile caller on an Extricom network associates with the central switch itself, which then sends the packets to the appropriate AP, with no need to re-authenticate the client and re-establish the connection on another radio. Zero-latency mobility, as the company's press release terms it.

The demo at Demo, at least according to the plan that Confalonieri described to VoIPplanet in a pre-event briefing, involves broadcasting three separate data streams simultaneously to three separate access points-on the same channel, in the same room. That would be tripling the effective bandwidth for that channel-and for all channels available to the 'mode' of Wi-Fi being used.

Wide availability of the EXSW-2400 is expected early in the second quarter of this year.

By Gabriel Brown
October 11, 2004

Israeli startup Extricom Ltd. claims to have developed a "break-away" enterprise wireless LAN architecture that is unaffected by co-channel interference and will enable networks to operate at "full modem speed" and with "perfect coverage."

The bold claims were made as the firm announced it has raised a further $5.6 million in second-round funding this week, led by Vertex Venture Capital. When completed, the $8 million round will bring total investment to $11 million (see Extricom Scores $5.6M).

Extricom's system is designed around a centralized switch and thin access point architecture, similar to Aruba Wireless Networks, Symbol Technologies Inc. (NYSE: SBL - message board), and others. So far, so normal.

What makes the company different, says CEO Gideon Rottem, is that its access points can be deployed in dense configurations and deliver superior throughput per user, without the need for cell planning and RF management, and with zero handoff time between access points. "It's an optimization of the 802.11 PHY."

The key technology that makes this possible is a per-packet adaptive architecture that adapts to its RF environment for each packet sent across the wireless network. Also described as "specialized link-optimization algorithms," this software enables frequency reuse of each 802.11 RF channel, multiplying the aggregate capacity by up to 60 times compared to regular 802.11 networks, says Rottem.

Extricom's switch and access point products are based on commercial 802.11 RF silicon, ported to low-cost, small-footprint field-programmable gate arrays (FPGAs) in place of the memory and processors found in regular access points. The vendor claims this can reduce the bill-of-materials (BOM) by up to 30 percent versus devices built around rival products.

Recognizing the enterprise wireless LAN market is crowded by large incumbents like Cisco Systems Inc. (Nasdaq: CSCO - message board) and Nortel Networks Ltd. (NYSE/Toronto: NT - message board), as well as startups such as Airespace Inc. and Trapeze Networks Inc., Rottem isn't planning a full-frontal assault on the enterprise. Instead, Extricom is pitching itself as an OEM offering for vendors already in the market and looking to make superior RF performance a core feature of their next-generation products.

Already there are plenty of signs that the industry is moving in the direction of denser and more robust deployment models for heavy-use enterprise customers (see WLAN Gets Dense , Airespace Finds MIMO, and Aruba Grids Up). There is also another stealthy Israeli startup, Stellaris Networks, touting technology that sounds similar to Extricom's.

And there are examples of equipment vendors, such as Chantry Networks Inc. and Netgear Inc. (Nasdaq: NTGR - message board), adopting software that automates many aspects of RF management, and which may ultimately be embedded in 802.11 chipsets (see Propagate Looks to Clear the Air). At this stage, however, most enterprise 802.11 equipment vendors seem more focused on developing application-layer partnerships and sales channels, than on deep re-engineering projects. It is unclear how much appetite exists for a full-scale swap out of the radio-layer, at least in the short term. "There is some pain," agrees Rottem. "And that's why this is an 18-month process."

By Ed Sutherland
October 9, 2004

Could the lowly 802.11b become a 99Mbps speed-demon? How about 802.11a breaking the 1Gbps barrier? Difficult to imagine? Israel-based Extricom says its possible-if Wi-Fi would just stop interfering.

Extricom believes it has the answer to speeding up Wi-Fi, along with readying enterprise WLANs for demanding wireless applications, such as Voice-over-Wi-Fi. The company's "Interference Free Architecture" triples both the available channels and bandwidth of 802.11a, b and g.

"The next big wave in WLAN will be performance and deployment in the enterprise," said Gideon Rottem, Extricom's CEO. "Current technologies all fall short, creating a gap that Extricom is poised to fill."

Extricom believes solving the problem of co-channel interference allows the continued growth of the Wi-Fi market.

"Without a solution that eliminates co-channel interference, there would be a very solid limit to how fast, and how far, this market could expand," according to the company.

Rottem said the announced $5.6 million in funding from Vertex Venture Capital and Magnum Communications Fund "will be used primarily to propel penetration of the company's first round WLAN products in North America and in the Asia Pacific markets."

Described as a switch and AP combining hardware and specialized software algorithms, the products from Extricom-now in Beta testing-will be available in the first quarter of 2005 to "box vendors for the enterprise market," says Atara Lev, spokesperson for the Herzlia, Israel company.

Extricom's penetration of the WLAN switch market will be a two-prong process. Rottem says a finished product will be first available in the first part of 2005 and then Extricom will provide custom chips to original equipment manufacturers. That finished product will be a "central access unit," similar to that produced by switch vendors Aruba, Trapeze and Airespace, according to Rottem.

This "break-away WLAN architecture...eliminates the coverage and capacity limitations of traditional WLAN architectures, and the need for cell-planning and site surveys-the most expensive aspect of owning a WLAN," according to Extricom.

Extricom's system uses per-packet adaptive techniques along with channel reuse to create a "high performance voice and data network where each user's link is optimized anywhere and at any time in the network," according to a prepared statement.

"The outcome is a network that operates at full modem speeds ubiquitously," says the company. "Extricom sharply increases capacity and scalability in the face of a hostile, in-building RF environment."

The new technology is backed by 10 patents "related to the ability to deploy a network that operates unaffected by co-channel interference".

Extricom's products come down on the side of intelligent wireless switches and "ultra-thin" APs. The APs have no radio or processor. While device agnostic, in order to achieve the high data rates and throughput, all Extricom hardware is needed, according to Rottem.

A white-paper from Extricom provides examples of the impact of its technology. 802.11g, rated at 54Mbps on one channel could reach 486Mbps operating on all three available channels. The increasingly popular 802.11a standard could attain 1.296 Gbps, claims Extricom.

A combination of chips and software will enable Extricom's customers to forget about co-channel interference and transmit on all available channels. Unlike the current method of not placing APs using the same channel side-by-side, access point using Extricom's "break-away WLAN architecture" will use the same channel. Rather than dividing APs among the three channels available to 802.11b, Extricom-powered APs would use all three channels at once. Tripling the available channels would also triple the available bandwidth, claims the company.

Rottem believes his company is looking at the "next generation of wireless" and will intersect the public's need for more bandwidth.

"The current approaches by competitors in this market are fatally flawed," believes Rottem. "They will never provide unfettered performance, and the performance will only get worse as demand increases."

By Gabriel Brown
April 29, 2004

While many vendors are trumpeting advances in voice over WLAN (also known as VoWiFi or wVoIP), they are nonetheless working against fundamental problems inherent in the IEEE 802.11 standard that underpins most wireless LAN technology-and therefore most wVoIP.

Extricom Ltd., an Israeli R&D company, claims to have overcome these problems while remaining compliant with all current flavors of 802.11-.11b, .11a, and .11g. The limited number of RF channels, interchannel interference from adjacent channels, and restricted range and capacity are all dragons Extricom technology has slain, according to CEO Gideon Rottem.

The result: a wireless LAN architecture highly friendly to voice traffic.

The Extricom system consists of a centralized switch (not an unusual feature in today's Wi-Fi world) "directing," in the company's parlance, groups of ultra-thin access points. "Ultra-thin" means there is a complete absence of "intelligence"-software or storage-on the units. They are just radio conduits linking clients (phones and computers) to the switch.

"There's a general consensus in the industry that centralized decision making is better [than distributed]," commented CEO Rottem. "Extricom has taken this to its logical conclusion," he said, "making all decisions at the center."

What this means is that the decision maker (switch) is aware of the state of the entire network for each packet that travels it, so each packet is routed to the optimum path, providing "dynamic, packet-by-packet diversity processing," as Rottem terms it.

In using the Extricom system, a client associates not with an access point, as in most other switch-based systems, but with the network-the switch. The APs are mere pipelines to which the switch dispatches packets.

If the stream is a phone call and the client is moving through the network, there is no need for the client to reassociate with new APs as the caller walks along. The switch just directs the packets to the most appropriate AP, based on actual conditions. Thus there is no latency or "handoff hiccup"-a key problem for mobile VoWiFi.

Furthermore, since adjacent channels are not broadcasting (due to optimized central management), there is no RF interference in the system. This makes for greatly increased channel use efficiency, and ultimately to increased network capacity.

The same goes for range. Cancel interference, and the access point serves a larger space.

Furthermore, each Extricom AP can support up to four radios, which can broadcast any flavor of 802.11 a, b, or g, and can be specified in any combination. Different kinds of traffic can be assigned to specific radios, with, say, 802.11b for voice (since most Wi-Fi telephone handsets currently use .11b), .11g for normal data, and .11a for video.

In a Yokahama, Japan-based trial, the Extricom product line has been deployed to support a telephone system on three floors of an office building, with users moving freely throughout the space. Extricom claims "wireline voice quality" for this pilot.

The Wireless Switch/Ultra-Thin Radio Points (the official product name) combination will be officially announced in early May, when it will be available in quantity. The system will be packaged as an eight-port switch bundled with eight APs, at a cost of between $8,000 and $14,000, depending on purchase volume. A 32-port system is planned for later in the year.