SIPdomain-to-numericPrefix Mapping
Dialing a direct URI can be difficult since phone keypads do not usually include characters other than numbers. SIP Broker maps – for instance – 'Ekiga.net' to '*673', so you would just dial '*673' followed by the number in the SIP address. This works for providers peering with SIP Broker to dial out.
There are over 1000 of these mappings, allowing someone to reach any open SIP proxy (that is, any SIP proxy that doesn't block incoming SIP calls from non-business-partner external domains).
In addition, SIP Broker allows to register shortcuts for SIP addresses that can then be dialed as '*011' followed by the shortcut.
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