SAN MATEO, Calif.—Juniper Networks Inc. (Sunnyvale, Calif.) is unveiling its newest Internet core router this week, presenting its latest challenge to the market dominance of Cisco Systems Inc.'s GSR 12000 family.

Juniper said its T640 will allow routing to be distributed among multiple boxes, making it only the second company to bring such an architecture to market, behind upstart Avici Systems Inc.

Targeted at both core installations and network points-of-presence (POPs), the T640 succeeds the M160 as Juniper's highest-end router. Juniper is calling the T640 an Internet Routing Node, rather than a router, because multiple boxes can be connected to act as a single router, although that capability won't be available until 2003.

That "matrix" capability, as Juniper calls it, is reminiscent of the distributed router architectures being touted by startups including Avici, Caspian Networks Inc., Hyperchip Inc. and Pluris Inc. It's a crucial technology, its advocates say, because the next generation of routers is being crafted for scaling — the ability to grow without undergoing a costly "forklift" replacement of the router itself.

Juniper's approach relies on a second box, the TX Internet Switching Node, to link multiple T640s, effectively turning them into a single large router. The first TX will connect four T640s, with future versions connecting eight or more of the routers.

The TX probably won't be released until next year, said Tom Jacobs, Juniper product manager. The box uses the same ASICs as the T640, though, so it could be brought to market quickly if needed. "We're not gated by anything other than the maturation of the VCSEL [vertical-cavity, surface-emitting laser] technology, and that's close," he said.

The T640 uses a distributed architecture internally, but without the TX, it lacks the ability to grow beyond its 640-Gbit/second throughput limit. For that reason, Avici officials were quick to criticize Juniper's announcement, saying it hasn't fulfilled the need for a distributed router architecture.

Further, Juniper is handicapped by the need for the TX box to link T640s, said Esmerelda Swartz, director of marketing at Avici. "You're introducing another box in the model, which in itself is a complex solution," she said.

Swartz also criticized the T640 for its lack of low-speed interfaces, forcing carriers to retain separate boxes for handling traffic levels such as OC-3 (155 Mbits/s). This poses a problem because carriers want fewer boxes in the network and want to lower the number of hand-offs needed to aggregate traffic, she said.

"That is how you save carriers money. You support aggregation, peering and core in a single platform," she said.

Quick to grab

Still, Juniper may be hoping to trigger some market share gains by releasing the "T" boxes now, as carriers have been quick to grab newly available technology. OC-192 router interfaces, which were nonexistent before 2000, already comprise half of the market in large routers, said Tam Dell'Oro, president of research firm The Dell'Oro Group.

In fact, Juniper got a boost by beating Cisco to market in the OC-192 race. After it began shipping OC-192c (10-Gbit/s concatenated) interfaces in the second quarter of 2000, Juniper saw its market share for large routers climb to more than 30 percent, as measured by the Dell'Oro Group. But Cisco rebounded after producing its own OC-192c interfaces in the first quarter of 2001 and has pushed Juniper back to a 27 percent share.

The key is that the core-router market is not like the consumer market, where early adopters represent a handful of sales.

"I have seen it year after year: When there are new products, and if the manufacturer is significant and credible, it can move a market," said Dell'Oro. "Generally, service providers migrate to the new generation of platforms regardless if whether they're being used at full capacity or not. So you load it up with low-speed ports — so what? You get the thing installed [and can populate it] for the next four years."

Still, Juniper will have to fight a lingering telecom recession if the T640 is going to boost its market share the way the M160 did.

Juniper already has announced three customers who have installed the T640: Verio; France Telecom's R&D division; and the National Science Foundation's TeraGrid Project. In addition, the Internet-2 project plans to use the T640 in its Abilene backbone network.

The T640 fits in half a telecom rack and has the capacity for 32 OC-192c ports or eight OC-768 (40-Gbit/s) ports. Juniper won't roll out OC-768 interfaces just yet — again, due to the need for more mature optics, Jacobs said.

The T640 is based on seven new ASICs — hence the "T" instead of the "M" used in Juniper's other product names. Developed during the past three years, the chips were built on IBM Corp.'s Blue Logic SA-27 process, which incorporates copper interconnects. They are the first copper-based ASICs to be used in a router, Jacobs said.