Chapter 4. SIP and the User Directory

In the previous chapter, we briefly introduced SIP, the Session Initiation Protocol, where we discussed how to register a telephone with FreeSWITCH. In this chapter, we will build upon that foundation and learn more about how we use SIP to connect users, both locally and around the world. SIP is a ubiquitous protocol in the VoIP landscape. In this chapter, we will:

• Learn the principle behind the FreeSWITCH user Directory

• Explore and configure the FreeSWITCH user Directory for the first time

• Learn how to connect FreeSWITCH to service providers

• Make modifications to the Dialplan and directory XML configuration

• Briefly discuss SIP profiles and User Agents