SIP Outbound is a SIP extension that focuses on keeping SIP connections alive over a NAT. The SIP user agent sets up two TCP/IP flows over UDP or TCP to two separate SIP proxys, called Edge Proxies. If one connection dies, the other takes over. The service user these connections for requests from the core to the user agent. All responsibility for NAT traversal is pushed to the edge, to the SIP UA in SIP outbound.
Implementations
- SIP Outbound - Managing client-initiated connections in SIP
- Edvina.net Presentation of SIP outbound
Implementations
- Kamailio 4.0 includes SIP outbound Support
- Counterpath Bria for iPhone supports Outbound
- BareSIP
