14 May 2010
Scaling up port density to meet IP traffic growth
Junkins predicts it won't be long before 100 Gbps networks become the norm for the Internet backbone. But meeting that demand would have been unrealistic -- financially and logistically -- with the switches NTT America was using in its edge network last year, he said.
Puny port density in the Cat 6509s was the culprit, Junkins said. The switches supported up to 28 10GE ports, requiring NTT America to run up to four of them in any given facility to meet intensifying IP traffic growth. Having to buy multiples of equipment not only increased capital outlays, it had two other strikes against it -- more boxes consumed more power and space in the POPs.
"Continuing to scale by adding more 10 Gigabit Ethernet bundles only gets us so far, so we need a higher-speed connection that will be a much greater [remedy for IP traffic growth]," Junkins said. "We were starting to see the [port] density [limitations] of the number of 10-gigabit ports we could provide."
Looking for the answer to scaling capacity to meet IP traffic growth, Junkins started more than a year ago to evaluate platforms from Cisco, Juniper Networks, Brocade and Force10 Networks. He selected the Cisco Aggregation Services Router (ASR) 9000, a carrier-class edge router with eight times the port density of the Cat 6509s. Today, they have capacity for 64 10GE ports, and Cisco plans to expand that port density to 160 10GE ports.
The Cisco ASR 9000 takes the same amount of rack space as the Catalyst 6509 despite the greater port density, Junkins said.