Polycom MGC Administrator Administrator's Manual page 431

Figure 7-16: IP-to-ISDN Over H.323 Backbone Call Flow Using Profile
Step 1. The H.323 endpoint dials 7011*1234 representing the gateway prefix,
the Gateways Link ID, the Delimiter and ISDN number as shown in
the above example.
The digits 70 represent the local gateway prefix defined in the
Network Service Properties and 11 is the local Gateway Link ID
retrieved from the Gateway Link.
Step 2. The local gateway automatically dials the remote gateway using the
string 9042*1234.
The digits 90 represent the remote gateway (H.323) ID prefix taken
from the local Gateway Link. The Remote Gateway H.323 profile
ID, 42, represents the configured Session Profile (ID E.164)
parameter defined in the To H.320 Session Profile Definition dialog
box. The * is the Delimiter defined in the Gateway Configuration -
General Settings dialog box. 1234 is the dialed ISDN number and
represents the destination endpoint number.
Step 3. The remote gateway dials 1234 and connects the call.
MGC Administrator's Guide
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