At 3GSM, Lucent attempts a revamp of the modern cellular base station

BARCELONA, SPAIN — At the back of its booth on the show floor of the 3GSM World Congress, hidden behind a closed door with frosted glass and protected by a sign saying “Invitation Only” is Lucent Technologies' brand new toy.

It's a plain white box that looks like the standard micro base station, but crammed inside of it there's a lot more. Lucent calls it a base station router, and within its frame Lucent has managed to combine the edge functions of a base station transceiver, a radio network controller and the core network functions of the GPRS support node (GGSN) and serving GPRS support node (SGSN). It's an entire radio access network in a single box, and Lucent believes it's the blueprint for cellular networks of the future.

Mike Iandolo, Lucent Networks Solutions group president of mobility access, said Bell Labs has been fine-tuning the technology for years, and while other vendors have also been “flattening” their network architecture, Lucent has finally managed to come up with the first single-box solution.

“The base station goes right into the IP cloud,” Iandolo said. “You don't have any separate boxes, which saves you on capex right there. Plus, we've eliminated all of the stops data has to go through, which improves latency on the network.”

A traditional UMTS network has a radio network controller (RNC) managing connections to dozens of base stations. From the RNC, packet traffic and call traffic are split off — call traffic is sent on to the mobile switching center while data traffic is diverted through the SGSN to the GGSN, where those packets make their way to the Internet or a private IP network. (In a CDMA network, those functions are performed by the packet data serving node or PDSN.) Each of those hops requires its own interface, backhaul and protocol, all of which continue to drag on that data before it ever reaches the Internet proper, Iandolo said. Each element requires its own housing and installation, and each has to be scaled to the network. The base station router eliminates the need for separate boxes and scales element functions down to match each other, one-to-one.

Ultimately, the router is a data-centric device, designed for 3G networks handling massive IP traffic. Lucent is building the device for UMTS/high-speed downlink packet access networks and eventually CDMA 1X EV-DO networks, which will flip the current voice-heavy model for cellular systems, Iandolo said. Lucent thinks the new architecture is the future of cellular networks. As a carrier's traffic increases and becomes more data-intensive, carriers will opt for the simple deployment of a flat IP network as opposed to the current distributed systems. Competitors, however, question whether the new concept is just wishful thinking.

Angel Ruiz, president and CEO of Ericsson's North American operations, said that although he sees some operational efficiencies in such an approach, the efficiencies also may create some drawbacks. “There are some advantages to handling things distributed, and there are advantages to handling things centralized, but if you put too many eggs in one basket, you also have a central point of failure,” Ruiz said. “A lot of times when people get wrapped up solely in technology they forget these things.”

Nokia has also been working on flattened architectures for the access network, but instead of wrapping the entire access network into a single box, Nokia has built a data-optimized version of UMTS, which allows carriers to devote specific spectrum to high-speed access. Called Internet-high speed packet access, the platform bypasses the RNC and the SGSN, sending IP traffic directly to the GGSN, creating a data-only complement to its UMTS portfolio. Martin Blades, director of systems marketing for radio networks at Nokia, said flattening complexity of the cellular architecture makes sense for specific network aspects but that vendors shouldn't flatten merely for the sake of flattening.

“I can't see how compressing to one box really makes a difference,” Blades said.