Erlang SIP business introduction

When talking about the SIP Protocol, many people first think of the VoIP service. So what else is there? Today we will introduce another embodiment of the SIP business-Erlang project called yxa official website http://www.stacken.kth.se/project/yxa/), can be said to be the Erlang on the SIP protocol stack and server implementation. In addition to the basic SIP service package release, transfer layer, and Transaction layer, yxa also provides a set of server functions in the form of independent applications, including the following.

1. incomingproxy

Implements the Registry's registrar function and can process the REGISTER request.

Implements the proxy server with transaction status, namely, transaction stateful proxy.

This is also the core function, which basically implements RFC3261 and provides most of the common SIP services.

2. outgoingproxy

It mainly helps clients of the SIP service to traverse NAT.

3. pstnproxy

Enable communication between VoIP users and general telephones.

4. appserver

Processing Branch forking) request and CPLCall Processing Language ). CPL allows administrators to define complex call processing and routing rules to implement advanced services.

5. Database Support

Mnesia, Mysql, LDAP, and plain text files. Mnesia is a distributed database that comes with Erlang.

6. Web-based Management Interface

The Web server also uses Erlang-based yaws. You can manage location services, user databases, and view running conditions. The following is a glimpse of the management interface:

7. RFC compatibility

RFC3261 SIP: Session Initiation Protocol
RFC3263 Locating SIP Servers
RFC3265 SIP-Specific Event Notification
RFC2916 E.164 number and DNS
RFC3581 using Ric Response Routing
RFC3326 The Reason Header Field
RFC4320 SIP Non-INVITE Actions (updates RFC3261)
RFC3327 Registering Non-Adjacent Contacts (Path: header)
RFC3856 A Presence Event Package for SIP
RFC3903 SIP Extension for Event State Publication
RFC3863 Presence Information Data Format (PIDF)
RFC4235 An INVITE-Initiated Dialog Event Package for SIP
And several other required RFC, such as DNS and MD5.

From the above SIP business, we can see that yxa supports Presence, that is, it supports rendering business.