Alcatel and Chiaro Networks Monday separately became the latest entrants -- or reentrants, in Alcatel's case -- in the core router market, an arena with high barriers to entry, such as product development cost, long sales cycles, two entrenched and dominant players, and sharply reduced customer spending.

Alcatel announced the 7770 Optical Broadband Exchange (OBX), a re-spin of its 7770 Routing Core Platform, an ambitious attempt at terabit scale first announced in late 2000 and shipped in mid-2001. Carriers, however, requested Alcatel start over again with a smaller footprint that can fit in their equipment racks.

Alcatel scaled the 7770 down into a half-rack system that it now calls the OBX. The OBX features 100G bit/sec of line capacity and a 320G bit/sec switching fabric per half-rack shelf.

Alcatel says the half-rack design makes the router more versatile as well, enabling it to support smaller core and edge applications in addition to large core requirements.

Alcatel’s OBX retains the 7770’s distributed switching and forwarding architecture, and cards from the Routing Core Platform are forward-compatible with the OBX, company officials say.

The system also includes Alcatel's ACEIS fault-tolerant routing technique for 99.999% reliability in a single system. Alcatel says ACEIS alleviates the need to deploy a duplicate router for redundancy.

Nine racks of OBX line cards, switching, and control shelves result in 1.9 terabit/sec of line capacity and over 5T bit/sec of switching, Alcatel claims.

Chiaro offered a preliminary glimpse into its Enstara router, an optical crossbar switch that leverages optics to switch packets internally between line cards. Chiaro claims to have 50 patents issued on Enstara's design, including a so-called Optical Phased Array (OPA) technique which uses scores of gallium arsenide optical waveguides in parallel to refract light, under electrical stimulation, from a single ingress fiber to multiple egress fibers.

OPA uses interference patterns to bend light to desired destinations, Chiaro says, and can achieve switching speeds of 30 nanoseconds. A 64-by-64 Enstara switch with 128 connectors is about the size of a briefcase, company officials say.

Enstara is capable of supporting "hundreds" of 10G bit/sec interfaces in its initial release, Chiaro officials say. It is shipping and deployed now at the California Institute for Telecommunications and Information Technology next-generation grid network, OptIPuter.