SIP as a protocol is easy to understand, and implement. It enables distant computers, phones, TV and other client software to communicate. SIP messages are similar in structure to the HTTP format, and for convergence, SIP uses the same error codes, so that for example the Web code 404 "Page not found" is the same as the SIP code 404 "Address not found".
SIP addresses are based on the tested email address format and so sip:user@odyssey-systems.co.uk could easily be a sip device address. SIP also uses the web DNS to make its communication more extendible.
When implementing SIP, it is important that the devices and services have long term reliability without continually updating servers and clients, but with the ability to add to the range of features with new devices and services as they become available. SIP permits this because:
- SIP messages are in a text format for ease of reading and debugging.
- It uses the mime type description to enable auto-running of associated applications.
