Cisco to take users on a tour of 'Milan'

Atlanta - Cisco Systems, Inc.'s strategy for migrating campus nets to gigabit speeds involves a lot more than just Gigabit Ethernet.

It hinges on "Milan," a line of high-end, multigigabit Layer 3 switches in development that are expected to scale to 100G bit/sec over the next two years. It is also roote it NetFlow LAN Switching, an iteration of Cisco's packet caching technology for LAN switches.

And it includes new Gigabit Ethernet supervisor and switching modules for the Catalyst 5000 LAN switch line.

Cisco is expected to disclose its gigabit network road map and demonstrate Gigabit Ethernet modules at next week's NetWorld+Interop 97 show here. The road map comes at a time when observers are anxious for Cisco to begin delivering the goods from its $200-million acquistino of Gigabit Ethernet pioneer Granite Systems, Inc. (NW, Sept 9, 1996, page 8).

Cisco, traditionally a vendor that eschews standards, claims it is waiting for Gigabit Ethernet standards to stabilize before shipping the product early next year. Some analysts think these statements are a smoke screen designed to hide the possibility that Granite's technology was not all it was cracked up to be.

"As soon as they announced the Catalyst 5500 [last spring] and said they were waiting, we pretty much knew that they were blowing smoke at us," said Craig Johnson of Current Analysis, Inc., of Ashburn, Va. "We had heard rumors that they were having challenges in folding the Granite stuff into the architectures they were looking for."

Some analysts believe Cisco has been back to the Gigabit Ethernet drawing board.

"It's taking a long time to deliver the fruits of that acquisition," said Nick Lippis, president of Strategic Networks Consulting, Inc. of Rockland, Mass. "With all the information we have, or lack thereof, it seems to me that [another acquisition] is not an outlandish possibility."

Cisco will demonstrate Granite technology at NetWorld+ Interop 97, said Nate Walker, Cisco product line manager for high-speed switching.

While Cisco fiddles with Granite, the company hammers away on the Milan project. According to users and analysts briefed by Cisco, Milan is based on a crossbar switching matrix, similar to the one at the core of Cisco's 12000 Gigabit Switch Router (GSR) for Internet service providers.

Indeed, some believe Milan is the GSR scaled down and priced for campus backbones. Cisco seems to corroborate that.

"We'll take [GSR] technology, accelerate it and get it in the right price range for the campus," Walker said. When asked specifically if Milan is the campus GSR, Walker replied, "I understand the question, but I can't comment on anything under development."

The first release of Milan is expected to ship next year at 20G to 40G bit/sec. Subsequent configurations are expected to scale from 50G to 100G bit/sec. Milan will require new LAN switching modules because the Catalyst 5000 and 5500 modules connect to a bus-based backplane.

Also expected next year, and to be on display at NetWorld+Interop 97, is a NetFlow Feature Card for the new Catalyst 5000 Gigabit Ethernet supervisor module (NW, July 28, page 24).

NetFlow is key for scaling Cisco nets to gigabit speeds because it provides wire-speed Layer 3 forwarding in the tens of millions of packets per second and applies Cisco IOS network services, Walker said.

It may take some doing, though, to convince users that NetFlow really delivers.

"I have yet to really see the benefits of it," said John Dundas, project manager for CITnet 2000 at the California Institute of Technology in Pasadena. "I haven't seen the promise of increased throughput really met with that technology."

Perhaps NetFlow needs the new Gigabit Ethernet modules in order to perform. The new supervisor module, upon which the NetFlow Feature Card sits, will sport Gigabit Ethernet uplinks. It will be augmented by 12G bit/sec Gigabit Ethernet and Gigabit EtherChannel switching modules for the Catalyst 5000 line.

The supervisor module is slated to ship in the first quarter of 1998, while the switching modules are scheduled to ship in the first half of 1998. B.V. Jagadeesh, vice president of engineering at Exodus Communications, Inc., of Santa Clara, Calif., is expecting his beta shipment in four to six weeks.