To create this lab, some experience with Asterisk is required for the voicemail integration. This lab is relatively hard to implement. Some IP phones hardly send the busy message because they have more than a single line. It is important to use all the lines before to get the 486 Busy Here message. I like to do this test with two softphones, Xlite and Zoiper, in the same computer. When you reject a call in Zoiper, it sends a 486 Busy Here message to the SIP server. We will reduce the INVITE timeout in order to make the tests easier and less cumbersome. We can change the SIP timers using the following parameters:
modparam("tm", "fr_timeout", 5) modparam("tm", "fr_inv_timeout", 10)
The test for call forward is done on two occasions:
Test the call forward for unanswered calls: From the extension 1001, call the extension 1002. Do not answer the call at the user 1002. The system will forward the unanswered call to the user 1000.
Test the call forward on...