A new emphasis on video in IP networks may soon demand that service providers and equipment providers take a new look at the role and placement of the Broadband Remote Access Server (B-RAS).

Here's the problem: The B-RAS device is a central aggregation point where service providers accept, authorize, authenticate, and manage Quality of Service (QOS) and policy enforcement for hundreds of thousands of users requesting broadband services. But in the past, the B-RAS was used primarily for broadband data traffic; in an IPTV world, carriers fear the B-RAS may become a bottleneck.

“IPTV is a very bandwidth-sensitive service,” says Jefferies & Co. analyst George Notter. “When the subscriber is watching IPTV and changes the channel, that query cannot go all the way to the central office and back; the risk is that video latency will occur.”

Nothing will inspire the rage of IPTV viewers like screen freezes caused by network snags. After all, we might be talking about the season finale of Desperate Housewives here -- the stakes are that high.

The B-RAS traditionally has resided at the edge of the service provider’s core network, but service providers are increasingly moving that functionality outward, away from the core, Notter says.

“You’re starting to see different approaches emerging around B-RAS. Carriers would rather have the B-RAS in the central office, but in the future the B-RAS will move closer and closer to the customer,” Notter says.

There is considerable debate among service providers and equipment vendors on the issue. The vendors fire their salvos through white papers and new product feature sets.

Redback Networks Inc. (Nasdaq: RBAK), for instance, will tell you that the B-RAS should reside just behind the DSLAM at the local office, while others are vocal about their preference for placing the B-RAS closer to the central office.

The service providers, meanwhile, speak through their RFPs.

BellSouth Corp. (NYSE: BLS) released its RFP for a new IPTV network last August, and the RFP both states the architectural philosophy of the RBOC, and serves as a call out to vendors to provide equipment to facilitate those ideas.

With regard to broadcast TV streaming using IP multicast, BellSouth may deal with the B-RAS bandwidth issue by not dealing with it.

“The role of the B-RAS in BellSouth’s IPTV network will probably not include a lot of video,” says Heavy Reading analyst Graham Beniston. “They want to keep lots of B-RAS capability, but they see they need much more bandwidth for high percentage usage of video on demand.”

Beniston says the BellSouth RFP may be a sort of challenge to the vendor community to come up with better answers. “I think they are throwing the challenge to the B-RAS vendors: ‘Can you handle it? Well, can you?’”

For example, the RFP suggests BellSouth may spread some B-RAS functionality over several boxes in its fiber-to-the-curb (FTTC) network. Some B-RAS capability may reside in hardened units under the street (close to the subscriber), Beniston said. Vendors, presumably, will have to address such ideas in material terms in their proposals, or suggest something better.

If the role of B-RAS in IPTV is just now being worked out in this way, what implication does this hold for the future health of B-RAS equipment vendors?

Beniston says it is neutral for vendors already entrenched in the market, while it may be bad tidings for smaller vendors trying to break in. Overall, the B-RAS market will continue to grow “moderately” because the need for B-RAS aggregation of data traffic alone is still growing, he says.

The Yankee Group sees evidence of this growth in the spate of B-RAS RFPs worldwide, leading to their conclusion that the global B-RAS market will grow at a five-year compound annual growth rate of 25 percent from 2003 to 2008, when it will exceed $1 billion.

BellSouth said in August, when it released the IPTV RFP, it would announce a winner in the next three months. The odds-on favorite to win, according to several sources, is DSLAM incumbent Alcatel SA (NYSE: ALA; Paris: CGEP:PA).

— Mark Sullivan, Reporter, Light Reading