Chapter 5. How To Configure Advanced SIP

In the Matching From Header table, you define from which network the calls can come. You can also select what the From header (that tells who is calling) should look like. This is used when matching requests in the Dial Plan table below. Name each definition properly, to make it easier to use further on.

In this case, we want to match on calls coming from the IP-PBX. This will ensure that only users who have been autorized by the PBX to use the SIP trunk will be able to make outgoing calls.

In the Matching Request-URI table, you define callees. This is used when matching requests in the Dial Plan table below.

In this case, you want to define the calls that should be routed to your SIP operator, which is call destinations where the usernames consist of numbers only, as these most likely are intended to go to the PSTN network. Call destinations that look like helen@sip.ingate.com should not be routed via the SIP operator, but be handled by the Telecommuting Module itself.

You can let users call international numbers with a + sign instead of the international prefix. For this, define the + sign as a Prefix, which means that it will be stripped before the call is forwarded.

The Min. Tail is set to 4 here, to open for the possibility of three-digit local extensions, which should not be handled by the Dial Plan.

In the Forward To table, you define where calls should be forwarded. This is used in the Dial Plan table below.

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