Tel Alias

From Pbxnsip Wiki

While it is usually okay to have names with a domain scope, there are situations when you need a global scope for names. For example, if you want to assign DID numbers to accounts (e.g. executive extension) in different accounts, the PBX can locate the right domain based on the tel: alias.

tel: alias names start with the string “tel:”. Everything else is exactly the same as with other accounts names (for example, tel:2127654321). That means if you have to, you can also include alphanumeric characters. So tel:abcdef would be a valid name. However, in most cases the tel: alias will use only numbers. But it might also make sense to use tel: alias names that include a + symbol in the front, e.g. tel:+886911765324.

Tel:alias are not only used for Inbound Routing. They are also used for presenting the Caller-ID to the outside world (see Outbound Calls on Trunk). Even if you have only one domain, it makes sense to use tel: alias names for the Caller-ID presentation. Invitation emails for scheduled conferences search also for tel: alias names when indicating what conference room number should be included in the email.