Redundant pair of Mediant 2600 Session Border Controller - with 0 SBC sessions (bare bones) and 0 transcoding sessions supporting software upgrade up to 600 redundant SBC sessions and up to 375 transcoding sessions or 600 transcoding session with addition of MPM4B. See release notes for transcoding capacity per coder. Includes a pair of Mediant 2600 chassis each with dual power supply, AMC module with 1 CPU AMC sub module, 2 networking AMC sub modules with 4 x redundant 1000Base-T GE copper interface and a DSP AMC sub modules with 2xDSPs.