SIP INVITE Header format

General

Information about the format needed to be used within the SIP INVITE for outbound calls with regards to the FROM, TO and CONTACT headers.

Product

• Voice

Steps

The SIP INVITE  should adhere to certain standards.

• Userpart: E.164 internationally formatted number which is owned by the customer or purchased from CM.COM. E.g. +31761234567

• Hostpart: PBX external IP address

• Portnumber: standard port 5060. A different source port can be used which needs to be reflected in the SIP account endpoint configuration within the Voice Management portal.

• Using port 0 we will send the response back to the used source port.

FROM/TO/CONTACT: <userpart>@<hostpart>:<portnumber>

• Calls using the same A- and B-number will be blocked by our SIP Gateway

• Calls are routed with the information received in the CONTACT and VIA headers.