AT&T Inc. (NYSE: T) and Comcast Corp. (Nasdaq: CMCSA, CMCSK) are each using 100Gbit/s router connections somewhere in their networks, according to a Monday press release from Cisco Systems Inc. (Nasdaq: CSCO).

The release announces new cards for packet-optical transport on the CRS-3 core router. It also boasts about the CRS-3 in general, though, and in doing so, it quotes the two service providers saying they've deployed 100Gbit/s connections on their CRS-3s. (See Cisco's Core Router Goes Packet-Optical.)

Why this matters
We knew AT&T and Comcast wouldn't let Verizon Communications Inc. (NYSE: VZ) have all the fun, considering Verizon has already announced 100Gbit/s deployments in the U.S. and in Europe. It's interesting to see how quick the major service providers are to activate 100Gbit/s, and where.

Except the "where" is missing here. AT&T's statement only says that 100Gbit/s on the CRS-3 is live somewhere; that could be referring to short-reach, point-to-point connections. Comcast's statement does say its backbone and metro networks are "are 100G production ready today with live 100G optics carrying customer traffic," but again, no details about distances. (Cisco declined to provide further details; neither carrier was immediately available at press time.)

Verizon, in announcing its first 100Gbit/s U.S. deployments, specified three links it would light up: Chicago to New York, Sacramento to Los Angeles and Minneapolis to Kansas City.

For more
A look at the recent Verizon 100Gbit/s news and some 100Gbit/s background:

— Craig Matsumoto, West Coast Editor, Light Reading