Fulfilling bandwidth needs

Frame relay networks should get a bandwidth boost courtesy of two new software implementation specifications announced last week by the Frame Relay Forum.The specs, FRF.

Frame relay networks should get a bandwidth boost courtesy of two new software implementation specifications announced last week by the Frame Relay Forum.

The specs, FRF.15 and FRF.16, call for the splitting of frame relay traffic over multiple interfaces or virtual circuits. After splitting, the traffic is aggregated through software to operate as one frame relay network.

Enterprise customers clamoring for more bandwidth for applications such as videoconferencing should see an increase in affordable broadband offerings as a result of FRF.15 and FRF.16, according to forum President Lori Dreher.

In addition, the emulated frame relay interface will be well-suited to areas where facility constraints or service restrictions have made T-3/E-3 services prohibitively expensive.

"Bandwidth requirements are increasing," said Melanie Hanssen, vice president of marketing for the forum and executive manager for virtual data services marketing at MCI WorldCom Inc., in Richardson, Texas. "This is one of the fastest growing areas we have, and in terms of addressing our end users' needs, these agreements are among the most significant for the forum in the past year or so."

Specifically, the Frame Relay Forum agreements provide protocols and procedures for two specific modes of multilink aggregation. FRF.15 supports end-to-end (data terminal equipment-to-data terminal equipment) multilink, and FRF.16 supports user-to-network interface and network-to-network interface combinations.

By aggregating interfaces, virtual circuits or combinations of the two, network operators can design an emulated frame relay interface with more bandwidth than any of its constituent parts. The resulting service is also resilient because the emulated interface continues working even if some of the physical interfaces fail.

The interoperability guidelines will allow switch vendors to provide a software solution in place of expensive, proprietary hardware-based traffic aggregation, Hanssen said. As the market for high-bandwidth services such as NxDS1 and NxE1 continues to grow, users won't have to worry about limitations associated with proprietary implementations, she added.

The agreements are coming at the right time, according to analysts. Market demand for frame relay services is expected to reach some $14 billion by 2002, up from $6 billion last year, according to Rosemary Cochran, an analyst at Vertical Systems Group, in Dedham, Mass.

Frame relay is a packet mode service that organizes data into individually addressed units, called frames, rather than placing them into fixed time slots. Frame relay networks combine the port sharing and multiplexing characteristics of X.25 with the high speed and minimal delay of time division multiplexing circuit switching.

Frame relay also eliminates all Layer 3 processing and does only minimal error checking, resulting in greater throughput than with X.25.

The forum, an organization of frame relay users, vendors and service providers, was founded in 1991 as a nonprofit mutual corporation in Fremont, Calif.