Force10 Networks today added packet-over-Sonet capabilities to its TeraScale E-series switch/routers in an effort to help service providers transition from Sonet-based core networks to 10-Gb/s Ethernet pipes.

Rather than adding Ethernet cards to Sonet-based core routers, Force10 proposes adding Sonet cards to core routers whose underlying architecture is Ethernet-based, adding Sonet overlays to that Ethernet traffic. This design makes the platform much less expensive than equipment with an underlying Sonet architecture, Force10 said.

The company's new four-port line card, which allows service providers to pick OC-3, OC-12 or OC-48 speeds on a per-port basis, will be available in August for $100,000 each, Force10 said.

The company claims its solution is much less expensive than the one introduced by its rival, Juniper Networks, at this year's Globalcomm trade show in June.