Cisco Makes Metro Move
Big news? Yes and no. On the one hand there is nothing really new about the 7600 OSR. It's actually a combination of the switching fabric of Cisco's existing Catalyst 6500, mixed in with the Layer 3 IOS routing software from its olde worlde 7500 router. The resulting hybrid is garnished with some new and faster ATM, packet over Sonet (POS), and gigabit Ethernet interfaces at speeds ranging from OC3 (155 Mbit/s) to OC48 (2.5 Gbit/s).
“It's basically a Catalyst 6500 enterprise L3 switch that's been re-purposed to be used in the metro service provider space, like many of the other Layer 3 boxes” says Dave Passmore, research director for the Burton Group.
Cisco acknowledges that the 7600 OSR combines technology from these two product lines, but it emphasizes that it has added new features specifically for the carrier market.
“The OSR is really an extension of our routing products and allows customers to migrate to optical speeds,” says Chris McGugan, senior manager of marketing for Cisco’s Internet systems business unit. “It also provides very rich, high touch optical services that providers need.”
Some analysts like Deb Mielke, principal at Treillage Network Strategies Inc. see the new 7600 OSR as a way to fill in the gap between Cisco’s large GSR 12000 routers in the core, and the older and slower 7500 routers -- which are usually deployed in service provider points of presence (POPs). With a 256-Gbit/s switching fabric and a 30 million packet per second (pps) forwarding engine, Mielke sees the architecture working well to fill this need.
But others read the introduction of the 7600 OSR as a sign.
“Cisco seems to have finally acknowledged that the 7500 router has become obsolete for service provider networks,” says Passmore.
The new 7600 OSR can be used for basic metro aggregation, using the cheaper, high-density Catalyst 6500 interfaces, or it can be used in place of the 7500 for edge routing in a POP -- performing more advanced billing, traffic shaping, quality of service, and accounting. Cisco says that even with all these fancy features turned on, the 7600 OSR can still route at wire speed due to its Parallel Express Forwarding processors.
One advantage of the 7600 OSR’s familiar architecture is that the new chassis accepts line cards from both the Catalyst 6500 product family as well as the 7500 router. This will help users retain value in existing equipment.
“Cisco has done a great job at leveraging components from both the 6509 and the 7500 for the new box,” says Chris Kozup, research analyst with Meta Group Inc.. “If you look at the past [Catalyst 8540 and 5500] there has been little investment protection for customers wanting to move to the next-generation box.”
But there are some downsides. For one, the device doesn’t offer multiprotocol label switching (MPLS) in the first release. While many pundits point out that MPLS is still in its early stages of adoption, competitor Riverstone has already announced support for this feature in its metro products (see Riverstone Scores a Coup).
Another feature missing is support for resilient packet ring (RPR)-like protocols -- including Cisco’s own Dynamic Packet Transport (DPT) -- that will provide protection on ring-based topologies. Even though RPR hasn’t been standardized yet, the GSR 12000 and the 7500 platform both support DPT.
“ I believe the reason Cisco hasn't included MPLS or DPT in this release is due to the fact that they wanted to get this box to market so as to not lose customers,” says Kozup. “The Catalyst 6509 wasn't able to compete on the same level with competitive products from Extreme, Riverstone, and Foundry.”
-- Marguerite Reardon, senior editor, Light Reading, http://www.lightreading.com