oc-12

from The Free On-line Dictionary of Computing (8 July 2008)

Optical Carrier 12
OC-12

   <networking> (OC-12) A {SONET} rate of 12 * 51.84 = 622.08
   {megabits} per second.

   [Matches {STS-12}]?

   (1997-05-26)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

OC12
       Optical Carrier level 12 [622,08 Mbps] (SONET, STM-4), "OC-12"