# SBC
> Session Border Controller – a network device that secures and manages VoIP traffic at network boundaries

An SBC (Session Border Controller) secures, routes, and manages VoIP traffic at network edges.

## What is an SBC?
A Session Border Controller (SBC) is a network element deployed at the edge of a VoIP network to control and secure real-time communication sessions. It manages [SIP](/voip-glossary/sip/) signaling and [RTP](/voip-glossary/rtp/) media between different network domains.

## SBC functions
Key functions include [NAT traversal](/voip-glossary/nat-traversal/), topology hiding, call admission control, codec transcoding, [TLS](/voip-glossary/tls/)/[SRTP](/voip-glossary/srtp/) termination, DoS protection, and regulatory compliance (e.g., lawful intercept). SBCs are essential for VoIP service providers interconnecting with carriers and enterprise customers.

## Related Terms
- [SIP](/voip-glossary/sip/)
- [NAT Traversal](/voip-glossary/nat-traversal/)