SIP message processing involves performing the fixup operation on a complete SIP message. NAT ALG accepts and attempts fixup operations on all TCP segments that originate from or are destined This fixup is normally performedīy an application-layer gateway (also called an application-level gateway) (ALG) module that resides on the NAT device.īy default, support for SIP is enabled on the standard TCP port 5060 to exchange SIP messages. Fixup denotes the writing of the translated IP address back into the packet. That might belong to a private domain, and such messages must be fixed up when they pass through a Network Address Translation These SIP messages can contain embedded IP address or port information SIP messages that take the form of requests and responses. To describe multimedia sessions used for creating and controlling multimedia sessions with two or more participants.Įntities that are present in a Session Initiation Protocol (SIP) deployment communicate with each other by using well-defined Session Description Protocol (SDP) is a protocol that describes multimedia sessions.

To control attributes of an end-to-end call. Signaling allows call information to be carried across network boundaries.

Like other VoIP protocols, SIP is designed to address functions of signaling and session management within a packet telephony SIP provides an alternative to H.323 within the VoIP internetworking Signal the setup of voice and multimedia calls over IP networks. Cisco SIP implementation enables supported Cisco platforms to SIP can be configured to operate over TCP-based transports. SIP is a protocol developed by IETF for multimedia conferencing over IP. Session Initiation Protocol (SIP) is an ASCII-based, application-layer control protocol that can be used to establish, maintain,Īnd terminate calls between two or more endpoints. The NAT TCP SIP ALG Supportįeature adds NAT ALG support for fixing up TCP-based SIP messages. Gateway (ALG) is used with NAT to translate the SIP or Session Description Protocol (SDP) messages. That is configured with Network Address Translation (NAT) to be translated and encoded back to the packet.

The NAT TCP SIP ALG Support feature allows embedded messages of the Session Initiation Protocol (SIP) passing through a device

Cisco asa sip alg