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The choice of Samsung, Motorola and Nokia to provide Sprint Nextel with its WiMAX network was a clear victory for vendors that could offer infrastructure and devices, and sent the rivals lacking this advantage scurrying to create their own ‘ecosystems’. In the early years of a standard, interoperability tends to remain imperfect – according to recent research by Rethink, it was the second greatest concern to potential WiMAX deployers after cost – and so there is reassurance in depending on vendors which can ensure the various elements of the system coexist effectively. Those seeking to provide all the components, such as Motorola, play up their end-to-end capabilities, but a clear trend visible at last week’s WiMAX World show was for all suppliers, large and small, to pay far more attention than previously to creating strong relationships with partners, and establishing their own end-to-end offerings, combining a best of breed approach with guaranteed interoperability.
Of the infrastructure majors, Alcatel-Lucent and Nortel are most obviously lacking in device capabilities, a factor that kept them out of the Sprint Nextel contract, at least in phase one. Both are working hard to forge close alliances to fill their gaps. WiMAX and Wi-Fi are officially at the heart of Nortel's turnaround plan, along with its enterprise alliance with Microsoft, together with IMS, IPTV and other elements of the move to convergence and all-IP. During 2006, the company more than doubled its investment in WiMAX, redirecting resources from across the company - something Alcatel-Lucent also plans to do. Nortel has particularly focused on claiming headstarts in MIMO technology, and on building an ecosystem around the Taiwanese ODMs and device makers, most recently adding ZyXel, the world’s largest maker of residential gateways, many of them white label. Nortel had been heavily focused on the metrozone opportunity, and integrating WiMAX and Wi-Fi, but with serious doubts over that market, its most important strategic move will now be to play on its enterprise strengths and combine its WiMAX offerings more closely with these activities. This would bring in a new range of ecosystem partners, possibly even sparking a stronger interest in WiMAX from Microsoft, and would give Nortel a clear differentiator over more exclusively carrier-focused rivals.
Over at Alcatel-Lucent, the company is making its own gestures towards its lack of handset offerings with its Open Customer Premises Equipment (CPE) Program, and at WiMAX World announced an expansion its existing cooperation with Intel, and a new partnership with Kyocera Wireless.
The French giant has expanded its interoperability testing (IOT) efforts with Intel to cover Intel's latest fixed/mobile WiMAX silicon, the WiMAX Connection 2250 (see separate item), as well as its WiMAX MIMO-capable chipset for mobile devices.
It also created a joint development agreement with Kyocera Wireless to collaborate on the development of end-to-end systems based on Alcatel-Lucent’s 802.16e infrastructure and a variety of Kyocera devices including multimode cellphones, non-traditional wireless devices, PC cards and USB gadgets.
“The growing strength of our Open CPE Program shows how quickly the WiMAX ecosystem is maturing," said Karim El Naggar, head of Alcatel-Lucent's WiMAX business.
"We don't want to be a CPE vendor, but we want to strengthen the ecosystem for devices," said Michael Seymour, vice president of partnerships at Alcatel-Lucent's WiMAX Business Unit.
Just as important as interoperability between base stations and CPE – and more neglected to date in WiMAX – will be open interfaces between the access network and the core. Again, the debate focuses on whether it is easier and less risky for an operator to select an end-to-end system from a vendor, such as Nortel or Nokia Siemens, that can offer that, or to optimize the network for its own needs by selecting and integrating best of breed products. Vendors that only offer certain aspects of the network clearly favor the second approach, and aim to team with integrators to make the operators’ lives easier.
For best of breed strategies at the core, the critical interface is R6, which connects the WiMAX access network with the core IP network via the ASN gateway. Alvarion was an early mover in touting the benefits of R6, with its ‘Open WiMAX’ ecosystem program, announced at the start of this year. This allowed Alvarion to combine its base stations with ASN gateways from various vendors, notably Cisco, and offer a complete system to customers without their own integration capabilities. At WiMAX World, the company relying most heavily on the R6 story to gain profile was WiChorus, a start-up newly emerged from stealth mode, and focusing on the core network behind 802.16e.
The WiMAX Forum Network Working Group (NWG) has defined three implementation profiles for the R6 interface. Profile A enables mixing of radio and IP functionality in the base station and ASN gateway but components are tightly coupled, while Profile B "hides R6 in a locked black box", as Alvarion puts it. The option favored by best of breed advocates is Profile C , which supports openness and enables flat as well as hierarchical topologies. Alvarion also says that Profile C, by keeping the radio resource management functionality in the base station only, delivers a faster, optimized handover mechanism. (There is also the option of the R3 interface, which connects the IP-based ASN to the operator’s connectivity service network (CSN). Less attention is given to R3 because the majority of the operator’s capex is spent on components around R6, and they can gain the flexibility in shopping around for base stations and ASN gateways from different vendors.)
R6 is the key focus for WiChorus, a two-year old outfit headquartered in Silicon Valley, which has so far raised $25m in venture capital from Redpoint Ventures, Accel and Mayfield Fund. Its key product is its Intelligent Access Services Gateway, designed for the “fatter, flatter and smarter wireless core” that high capacity 4G will require. Content management, subscriber management and network optimization are handled from within the gateway, in line with the trend to flatten the network and apply more functionality and intelligence in a single place. Even the smallest, claims WiChorus, has more capacity than other “Linux pizza boxes” on the market.
R6 lies at the heart of the vendor’s ‘One Open WiMAX’ slogan, under which it aims to interoperate with as many base stations, home agents, servers (AAA, IMS, policy and so on) and other ASN gateways as possible. So far it has announced Bridgewater Systems, Redline, Aperto and chipmaker Sequans within its self-run interoperability testing program. It is pushing hard for the adoption of WiMAX Forum Profile C as the unified platform, probably incorporating some advanced features from Profile A, but with the “really proprietary” Profile B eliminated altogether. In this it is clearly supported by most of the best of breed vendors.
WiChorus believes it has a two-year headstart on any other start-up that may be working on WiMAX gateways, and that it will aim to work with the giants rather than compete against them – addressing some of the historic weaknesses of the infrastructure majors’ high end IP offerings (and perhaps angling for an acquisition, like Ericsson’s $2.1bn purchase of Redback in this space late last year). The obvious competitors will be Cisco and Starent. Cisco, according to WiChorus’ VP of product management Eric Andrews, lacks strong wireless awareness or flow capacity in its router-based offering (though could well look for an acquisition itself to strengthen its hand).
Starent, which is currently riding high on the financial markets, has focused mainly on 2G and 3G, but is starting to show an interest in WiMAX too. At WiMAX World it introduced its Home Agent for Mobile WiMAX, which supports seamless roaming between 3G and 802.16e, uniform delivery of Starent In-line Services and common billing. This joins the existing Starent ASN Gateway as part of the company's growing Mobile WiMAX portfolio, and the company has signed up Airspan as its first partner. Andrews believes Starent is not yet serious about WiMAX but is “amazing” in PDSN and so could be a major contender.
All this activity in the core is long overdue for WiMAX, especially considering that some of the end-to-end giants have less than stunning offerings on the ASN Gateway and HA fronts. One of the disadvantages of WiMAX’ heritage as an IEEE standard is that the organization does not focus on the core, and these activities were relatively late in starting within the WiMAX Forum, compared to developments in the RAN. If unaddressed for much longer, this leaves what Andrews describes as a “huge hole” when lining up against the 3GPP technologies. “The Forum is only just thinking about ASN gateways to knit together the base stations,” he commented. “But simplifying the network is vital for better economics.”
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