ADTRAN NetVanta 3140 5-Session SBC is the NetVanta 3140 SIP Router with the added bonus of the Session Border Controller Feature Pack. Includes 3 10/100/1000BaseT Ethernet interfaces and supports 5 simultaneous sessions. Need more than 5? No problem! The ADTRAN NetVanta 3140 SBC comes with up to 300 calls. That is 300 simultaneous sessions. Crazy, I know. Just call one of our awesome VoIP experts at 1-800-398-8647 and they will help you with all of your VoIP needs!