OIF technical committee chair Joseph Berthold, also a vice president at Ciena Corp., laid out some of the forum's plans in a discussion with EE Times at the Supercomm trade show last week.

The UNI allows routers to request connections and bandwidth from the optical network core, helping to automate the process of creating or removing connections. Because the UNI doesn't let the router know what's inside the network "cloud," many feel it makes a good complement to the emerging standard for Generalized Multiprotocol Label Switching, which lets routers contact specific switches inside the network core.

"A lot of carriers like this UNI model. They like not having to share everything," Berthold said. "What they're using it for is to drive interoperability between vendors and to allow them to simplify provisioning."

Perched amid other Supercomm exhibits on the playing field of the massive Georgia Dome, the forum's interoperability demonstration included 25 mini-booths of equipment cabled together, with a master scoreboard to indicate when vendors were requesting and creating links to one another's equipment. The participants — including a range of router, switch and transport vendors -- had completed a successful series of interoperability tests run at the University of New Hampshire in May.

Having completing a "straw" ballot at the end of 2000, the UNI specification is being reworked to accommodate some changes requested by carriers. The new version is expected to be released to a vote later this month, with voting to take place at the OIF's July 31 meeting in Vancouver. Should that version prove satisfactory or require only minor changes, the UNI will be brought to a principal member ballot, where it requires a 75 percent vote for final approval.

The OIF architecture group, which had been responsible for crafting the UNI, hasn't chosen its next project but is considering options inside the network "cloud," Berthold said. One possibility is to develop an interface allowing switches and wave-division-multiplexing equipment to swap information for management functions such as performance monitoring. The group also might study interdomain connections that would let one cloud talk to another, he said.

Berthold also said the architecture group might consider changes to the UNI to accommodate all-optical networking. All-optical switches aren't able to extract data from the light streams that pass through, presenting some challenges in terms of network management.

Meanwhile, the OIF's physical-layer group is "attacking the whole 40-Gbit per second problem," Berthold said. The group is developing 40-Gbit/second versions of standard optical-networking interfaces such as the system physical interface (SPI) and the serdes-to-framer interface (SFI). In addition, the group is in "the early stage of defining" a 40-Gbit/s version of the very short reach (VSR) interface that connects boxes within a central office, Berthold said.

The physical-layer group also is beginning an effort to define standards for the size and pinouts of tunable lasers. With no standards in place, tunable-laser vendors have to keep altering their ware to accommodate different module markers, Berthold said.