Sprint Corp. (NYSE: S) is considering a rollout of pseudowires for its wireless network and has issued a major request for proposal for the technology, Light Reading has learned. Pseudowires allow carriers to carve up bandwidth into small, packetized virtual channels, helping reduce the need for additional T1 lines to backhaul traffic from cell sites to the network backbone.

While the technology has been deployed in several international markets and in pockets of the U.S., a Sprint deployment would give pseudowire a major stamp of approval. (See Wireless May Boost Pseudowire.) The impetus? It's a money-saver.

"This would definitely be huge for the market," says Scott Clavenna, chief analyst at Heavy Reading.

A pseudowire is an emulation of a native service such as Asynchronous Transfer Mode (ATM), Ethernet, or Frame Relay over a packet switched network. Despite the promise, the technology has its drawbacks: Standards are still immature, so vendor interoperability is an issue. And it isn't bandwidth-efficient: It actually expands the number of bits in a data stream. But it's considered a less expensive alternative to T1 lines for cellular operators -- who find themselves going from supporting one or two T1 lines per base station to supporting four or more, as they try to keep up with data services, Clavenna says.

"If you use pseudowires, either right at the base station, or at some aggregation point in the network, you convert the TDM backhaul signals to packet and send them the rest of the way as 'virtual leased lines,' " Clavenna explains. "In a nutshell, you can greatly reduce the cost of backhaul of 3G data traffic and support a transition to Ethernet and IP."

A Sprint spokesman confirmed the desire to invest in pseudowire and additional backhaul technology.

"We use primarily ILEC T1 for backhaul," says Bruce Hoffman, director of technology development planning at Sprint Nextel in Overland Park, Kan. "There's a lot to be said for using ILEC T1. It's a well understood technology. The challenges are around the scaleability that's going to be necessary in the future -- scaleability both from a capacity perspective and also from an economic perspective."

"We'd need to have something that would emulate T1, which we might be considering," Hoffman says. "And logically we'd look at something like pseudowire. The RFP is in response to that. That's all I'll say about the RFP."

Companies dealing in pseudowire technology include networking giants like Alcatel (NYSE: ALA; Paris: CGEP:PA) and Cisco Systems Inc. (Nasdaq: CSCO), smaller companies like RAD Data Communications Ltd. , and specialists such as Axerra Networks Inc. and Hammerhead Systems Inc. Axerra and Cisco are believed to be among the favorites for Sprint Nextel's pseudowire deployment, according to several sources. RAD Data is in the running as well.

"We are involved in this bid," says Larry Jacobs, vice president of marketing at RAD Data. "We are involved in virtually every one of the [pseudowire] bids that are out there."

Other carriers are expected to jump into the pseudowire fray, too. "All large carriers from Tier 2 up have an RFI [request for information] or RFP out on this," says a source at a large gateway vendor, who is familiar with the RFP. "It's a big wireless-to-wireline convergence savings opportunity that anyone with both networks will have to do."Sprint's Hoffman says that one reason for the technology deployment is the carrier's upcoming EV-DO Rev A deployment. That will drive the need for backhaul bandwidth.

Sprint's EV-DO Rev A services will be available to initial customers at the beginning of 2007. Plans call for reaching a possible 220 million customers with Rev A by the end of the third quarter of 2007. Rev A promises data download speeds up to ten times faster than those of DSL, according to Sprint officials.

— Carmen Nobel, Senior Editor, Light Reading