> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip.md). # SIP and VoIP - [SIP](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip.md) - [NAP](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/nap.md): A network access point (NAP) is the entry point to another network or peer - effectively a trunk group. How NAPs bind SIP, ISDN and SS7 access points on TelcoBridges systems. - [NAT Traversal](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/nat-traversal.md) - [SIP Authentication](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-authentication.md) - [SIP Emergency](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-emergency.md) - [SIP NAP Polling](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-nap-polling.md) - [SIP Privacy](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-privacy.md) - [SIP Register Filtering](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-register-filtering.md) - [SIP Registration](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-registration.md): How SIP registration works: the role of the registrar, what a REGISTER request carries, and how an address of record is bound to a contact URI. - [SIP Session timers](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-session-timers.md): SIP session timers (RFC 4028): the refresh mechanism that lets user agents and proxies tell whether a session is still active, and how to configure it. - [SIP subscribe notify publish forwarding](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-subscribe-notify-publish-forwarding.md): How ProSBC and FreeSBC forward SIP SUBSCRIBE, NOTIFY and PUBLISH between users and a registrar, and which event packages phones typically subscribe to. - [SIP Transport Server](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-transport-server.md) - [SIP-I/SIP-T](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/sip-i-sip-t.md): SIP-I and SIP-T, SIP with encapsulated ISUP for interworking SS7 and SIP networks. TelcoBridges supports ITU Q.1912.5 Profile C, with listed exceptions. - [SIPREC Forwarding](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/sip/siprec-forwarding.md) - [H.248 and MGCP](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/h248-mgcp.md): H.248, also known as Megaco: the protocol a softswitch or media gateway controller uses to control media gateways. Applies to Tmedia 3.2 and 3.3. - [MGCP](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/h248-mgcp/mgcp.md): MGCP, the protocol a softswitch or media gateway controller uses to control a media gateway. TelcoBridges Tmedia and Tdev products do not support it. - [TB Media Gateway](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/h248-mgcp/tb-media-gateway.md) - [IP network and security](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network.md) - [Call Leg](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/call-leg.md) - [DNS](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/dns.md) - [Gateway Port](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/gateway-port.md) - [Leg](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/leg.md) - [NSE](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/nse.md) - [Product network interfaces cross-reference](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/product-network-interfaces-cross-reference.md) - [RAW IP](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/raw-ip.md) - [RFC](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/rfc.md) - [TLS](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/tls.md): Transport Layer Security (TLS) in VoIP: the handshake, how it secures SIP signalling, and how TLS profiles are configured on TelcoBridges systems. - [TUCL](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/tucl.md) - [UDP IP](https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/ip-network/udp-ip.md) --- # Agent Instructions This documentation is published with GitBook. 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