Polycom RealPresence RMX 1500 Administrator's Manual page 657

Gateway Calls
To invite two participants: SIP: 3456 and a PSTN participant whose number is 9251234, enter:
912000*3456**9251234.
Dialing from SIP Endpoints
Dialing String and Call Flow from SIP Endpoint to One, Two or Three Endpoints
The calling endpoints can dial to one, two or several endpoints (up to ten) in one dialing string. The dialing
string includes the following components:
[MCU Prefix in SIP Proxy] - The prefix with which the Collaboration Server is registered to the SIP
Proxy. This component is optional and is not required in most cases.
[GW Profile ID] - The ID of the Gateway Profile to be used for routing the call to the destination endpoint
or DMA, as defined in the Collaboration Server Gateway Profiles. It includes the parameters of the call to
the destination.
* - indicates H.323, SIP or ISDN connection protocol to the destination endpoint (followed by the appropriate
destination number). Placing this delimiter before the destination number causes the system to try to
connect the endpoint using H.323 first, then SIP and lastly ISDN according to the selected protocols.
** - indicates a PSTN connection to the destination endpoint (followed by the appropriate destination
number).
[Destination number] - the destination number as alias, IPv4 address or ISDN/PSTN number.
[@domain name] - the Collaboration Server domain name as registered to the SIP Proxy
The dialing string:
[GW Profile ID]*[Destination Number, first participant]*[Destination Number,
second participant]**[destination number]......*[Destination Number, tenth
participant]@domain name
Polycom®, Inc. 626