Climbing the metro mountain: Next generation device makes Sonet data-friendly

Just when you thought you knew the players in the metro optical space, a new company pops up. This week, Cyras Systems emerges with the K2, a new optical metro product to compete with Cisco Systems' 15454 developed by Cerent.

The K2 integrates the functionality of a digital cross-connect, Sonet add/drop multiplexer (ADM), ATM and frame relay switches, and it adds DSL, wave division multiplexing and multiprotocol label switching support, said Rafat Pirzada, vice president of marketing for Cyras. The system can scale to provide 40 Gb/s, and the cross-connect supports 768 x 768 STSs with STS-1 granularity, he said.

The K2 also supports "any card in any slot," Pirzada said. As carriers scale from OC-3 or OC-12 networks to OC-48 and OC-192, they can reconfigure the card via software; they don't need to buy a new card. The same flexibility exists for network platforms - shifting from frame relay to ATM is a software change.

Perhaps the K2's biggest draw is that it is optimized for data. Sonet ADMs from Fujitsu, Lucent Technologies and Nortel Networks now are clunky for data networks, Pirzada said.

"The first generation ADMs were very costly, they took up a lot of space and they were not very flexible in terms of the variety of interfaces they support, and their data support was pretty much nonexistent," he said. "We needed to build a next generation platform that addressed these issues."

Cerent was the first to succeed in this space, but it only addressed the cost and space savings, Pirzada said. Data-aware Sonet devices also have emerged, but they typically focus on the access market, supporting OC-3 and OC-12 interfaces. "The market took off in a much bigger way," Pirzada said. Service providers don't want OC-12 networks; instead, they are building OC-48 in the metro, he added.

"We have a next generation ADM and a data-aware device and combined them in a way that allows carriers massive scalability," Pirzada said. The K2 is data-optimized and gives carriers a mechanism to migrate to pure optical networks.

"Cyras is going with greater port density and higher scalability, and now a lower price point," said Scott Clavenna, principal analyst for Pioneer Consulting.

Cyras considers the K2 a "trans-metro device" because it works in the metro access, transport and core spaces. "We can take our platform in any market," Pirzada said. Though many start-ups target newer and smaller carriers, RBOCs generate 80% of the metro revenues, he said. That's where Cyras is focusing.

"We are building a product that fits the needs and the requirements of the major carriers," he said.

Most traditional devices require metro traffic to be converted to ATM, then put on the ring using "pseudo-Sonet," Pirzada said.

"If you convert non-native traffic, you are hit with a significant cell tax," he said. "The majority of traffic is frame relay and TDM, so you are losing half of your bandwidth efficiency. We treat data in a native format. We don't have to convert anything."

Sonet concatenation further muddies the efficiency waters because incremental growth isn't possible. Typically, a carrier that needs slightly more than an OC-3 is forced to provision an OC-12. Not so with the K2. "We take a Sonet pipe and break it up into any increment in an arbitrary fashion. If you need 300 Mb/s, you can make an OC-6. We don't force you to go to OC-3, OC-12 or OC-48," Pirzada said.

The market for this equipment is growing at an unprecedented rate, as suppliers add developed data-optimized Sonet ADMs, Clavenna said (see figure). The trick is to support incremental growth so carriers can efficiently fill STS-1s.

"Once you can do that, it doesn't make sense to do something different if Sonet is in the network already," he said.

"There is a large Sonet market in the metro area," Clavenna said. "All the big carrier networks are constructed to use Sonet equipment. They would rather deploy an improved Sonet box than deploy something completely radical."

Cerent might be Cyras' toughest competitor, but "there is room enough for both," Clavenna said. "Cerent has $1 billion of a $9 billion market. Cyras is going after the other $8 [billion] out there."