Redundant Mediant SE/VE Low Capacity (up to 250 sessions) Session Border Controller (SBC) product - with 0 sessions. This base platform can only use 25, 50 < 100 upgrade packages of SBC sessions and signaling sessions. It is possible to grow to more than 250 sessions in future upgrades only after purchasing either the SW/MSW/LH or SW/MSW/LH/R software upgrades first!