Amid multivendor interoperability demonstrations at the NXTcomm trade show in Chicago this month, Nortel Networks announced the formation of what it called a ‘PBT ecosystem’ comprised of vendors working together to publicize Provider Backbone Transport technology, a connection-oriented layer-two-based approach to Ethernet transport. John Hawkins, Nortel’s manager of carrier Ethernet marketing, spoke about Nortel’s PBT plans in advance of the show.

On the "PBT ecosystem": It’s a group of industry vendors, software vendors, solution providers and core systems vendors like ourselves creating a viable ecosystem for PBT-based carrier Ethernet solutions based on two activities: joint marketing and interoperability testing. Nortel will host plug-fests in our Ottowa labs from time to time, leading to real-life demonstrations of multivendor PBT-enabled carrier Ethernet solutions. The only thing we require is an interest in PBT. I don’t care if it’s a competitor or not, as long as it shows viable solutions. It’s an open thing. We’re welcoming anyone who has something to say. The intent to show that there’s a growing community of vendors that can provide PBT solutions.

On the latest version of Nortel’s PBT-based 8600 metro Ethernet switch: It includes enhancements such as the ability to do multi-link trunks, a link aggregation scheme that now maps PBT trunks into a multilink trunk. You can bundle a bunch of GigEs and make a 10-GigE link, distributing traffic over a discrete link that looks like one link to the Mac layer. The PBT trunk can either interface to or run over the multilink trunk, which gives carriers a lot of flexibility in terms of where they route bandwidth. If you have a requirement for a 5-Gb/s link, you can gang up 1-Gb/s links. It also has new SFP technology that allows 125 km of reach. That’s critical for things like data center redundancy and backup. And there are new OAM functions.

On PBT and control planes: The control plane is strictly an optional exercise at this point. All we need now is a decent management plane for setting up point-to-point links. That’s the tooling we have. Going into multitask and multipoint solutions is kind of the next step. We’re still studying it ourselves.

On Fujitsu’s new packet optical networking platform, which focuses initially on MPLS-based pseudowires: I’m not versed on their proposal. The reason we’re doing PBT is because extending the MPLS portion of the network from the core to access or into the metro is going to be expensive. That’s where PBT plays a role. I don’t blame [Fujitsu] for taking a wait-and-see approach. We’re trying to minimize the expense of packetizing the metro. You can do it with MPLS; it’s just going to be operationally complex. I think they’ll discover that.

On PBT versus “PBB-TE,” the IEEE’s name for it: I tend to fall back on calling it PBT because PBB-TE is such a mouthful.