8 Things to Know About Packet-Optical
Here's a glance at what we learned.
1. 400 Gbit/s or 1 Tbit/s: We don't know which is next
Panelists agreed that the industry needs to decide which speed node will be the focus after 100Gbit/s, but that didn't settle the debate about which speed it should be. Keynoter Shamim Akhtar, senior director of network architecture and technology at Comcast, spoke for a lot of carriers, saying it should be 1Tbit/s, but really, the industry is still thinking about it. (See Comcast Exec Wants 1-Terabit Optical Standard.)
Heavy Reading analyst Sterling Perrin did point out that the time to decide is now. Research on 100Gbit/s transmission started at about the same time AT&T Inc. (NYSE: T) began deploying 40 Gbit/s, which suggests that research on the next speed grade should be starting now, as 100Gbit/s deployments start rolling. That's not a scientific analysis, but his point was that it's not too early to start the work. In fact, it's arguably a little late.
2. 100 Gbit/s ain't cheap
Take it from Paul Savill, senior vice president of transport and infrastructure services at Level 3 Communications Inc. (NYSE: LVLT).
As a counterpoint, Randy Eisenach, a product planner with Fujitsu Network Communications Inc. , presented some numbers indicating that 100 Gbit/s provides a lower cost per bit than 10 Gbit/s, even if the 100Gbit/s equipment is a whole lot more expensive. If carriers start to agree, it could help 100 Gbit/s take off quickly.
3. IP over DWDM is dead
Or, at least, it should change its name to MPLSoDWDM, according to Infinera Corp. (Nasdaq: INFN) CTO Drew Perkins. His presentation attacked the Cisco Systems Inc. (Nasdaq: CSCO) and Juniper Networks Inc. (NYSE: JNPR) packet-optical strategies, which involve inserting a large Multiprotocol Label Switching (MPLS) switch into the network core. Cisco uses the CRS-3 router as that switch, but Perkins says that router is likely to be dedicated to the MPLS function, hence becoming an all-MPLS box in practice. (See Cisco's Core Router Goes Packet-Optical, Juniper Makes Its Packet-Optical Move and OFC/NFOEC 2011: Juniper OEMs an ADVA Box.)
"Dead" is taking it a bit far. On that same panel, Cisco's Greg Nahib -- who joined last year from Fujitsu -- said over-the-top players have been using IPoDWDM. Carriers use it more rarely, usually for video transport, he said. And other panelists seemed to agree that there's utility to having router-to-router connections in the core, traffic easily carried by IPoDWDM.
4. Packet-optical can't escape OTN.
Optical Transport Network (OTN) interfaces have gone from a nice option to a must-have, Perrin says.
Next page: What About Data Centers?