Introduction to the SIP Protocol on the SIP Wiki

There’s a new docmument authored by Tim Bosserman and myself that is a brief introduction to the SIP protocol on the SIP Wiki. As we say in the document:

The information here is not meant to replace the RFCs. It is not possible to duplicate all the information contained in 1000s of pages of RFCs in a few brief paragraphs.

We hope it gives an introduction to the main aspects of the protocol for the technically savvy reader:

It covers:

  • The SIP URI
  • Establishing a Call
  • SIP Registration
  • Frequently Misunderstood Aspects of SIP Protocol
  • DNS Issues
    • NAPTR Records
    • SRV Records
  • Resolving a SIP URI
  • Phone Numbers, DNS, and SIP
    • Introduction to ENUM

UPDATE: Can somebody please write a similar document for SIMPLE and the SUBSCRIBE/NOTIFY methods in practice?