Juniper routes 40-Gb/s over 10-Gb/s cores

Juniper Networks has introduced a new physical interface card for its T-series core routers meant to satisfy demand for 40-Gb/s backbones among carriers with 10-Gb/s networks.

Rising traffic volumes are sparking increased desire for 40 Gb/s long-haul networks, but most inter-city optical transport networks today are built with 10-Gb/s links, and an upgrade would be expensive. Moreover, 40-Gb/s optical links aren’t easy to monitor and manage across long distances. “You don’t know what’s happening until you get a complete loss of signal,” said Alan Sardella, product marketing manager for Juniper’s T-series routers.

To allow carriers to route 40-Gb/s IP links across their 10-Gb/s optical networks, Juniper has introduced a new physical interface card for its T-series core IP routers that uses inverse multiplexing to break a 40-Gb/s OC-768 signal down into four 10-Gb/s OC-192s.

The new card, available now, is based on pluggable optics and therefore doesn’t require a forklift upgrade, Juniper said. It has a reach of 80 km that the vendor will expand when pluggable optics allow it.

Using Juniper’s card, carriers also have the option of routing a full OC-768 signal directly into the multiplexer, bypassing the transponders and management system and transporting it across the network as an unmanaged “alien” wavelength. “It’s riding over us, but we cant do anything with it,” Sardella said. “It’s ‘ride at your own risk.’”

A year ago, Juniper’s chief rival Cisco Systems introduced integrated 10-Gb/s and 40-Gb/s dense wavelength-division multiplexing (DWDM) interfaces for its CRS-1 IP core router, naming Comcast as a customer. Sardella contrasted Juniper’s strategy from Cisco’s, saying, “They want one leg in the transport business and one leg in the switching or routing business. We’re a router company. We’re not going into the optical transport business. We’re just making our routers integrate more easily with your transport system.”

But a move Juniper made in this year’s first quarter did put Juniper “nominally” in the optical space, he admitted: The vendor started shipping a tunable 10-Gb/s Ethernet dense wavelength multiplexing (DWDM) interface card for its T-series routers as well as its M-120 router. Like the new 40-Gb/s card, the 10-GigE DWDM card has a reach of 80 km.