Polycom MGC Administrator, Руководство администратора

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MGC Administrator’s Guide
7-31
retrieved from the Gateway Link. The indicated asterisk (*) is the
Delimiter and the digits 1234 represent the destination Alias.
Step 2. The local gateway automatically dials the remote gateway using the
string 80208000. 8020 is the H.320 Gateway Parameter (access PRI
number) taken from the Remote Gateway Definition and 8000 the
Remote Gateway DID number taken from the Gateway Link. The
digits 8000 represent the destination endpoint alias in H.323 format.
The local Gateway queries the remote gateway where the routing
service has a pre-configured dial-in number (DID). The remote
gateway has no information but the Forwarding Service knows that it
has to request the string from the local gateway using the TCS4
channel. The local gateway translates the E.164 string into TCS4 and
sends it to the remote gateway.
Step 3. The remote gateway translates the TCS4 message into E.164 format
and connects the call to the remote H.323 endpoint. The remote
gateway forwards the Alias by retrieving the H.323 dialup sting that
has been stored at the local gateway. The local gateway sends the
string to the remote gateway and connects the call to the endpoint
dialing 1234.
H.320 to H.323 to H.320/H.323 Calls
When an H.320 endpoint calls an endpoint (H.323 or H.320), two different
methods may be used to reach the same endpoint: Address Book or Profile.
With the Address Book method, the carrier allocates the dial-in numbers to
the MCU/Gateway. Usually the carrier only transfers part of the number (the
last digits from the end of the number) to the gateway, for example, 1001 to
1600. Each dial-in number is assigned to a specific destination H.323 or
H.320 endpoint. The destination H.323 or H.320 endpoints will have to be
configured according to the dial-in numbers allocated to the gateway using
aliases in E.164 format. For example, if the dial-in number 1001 is allocated
to an H.323 endpoint, the endpoint alias will have to be configured as 1001 in
E.164 format. Each of the H.323 endpoints must register with the gatekeeper
using its E.164 alias. The H.323 endpoint dials the gateway prefix with the
H.323 alias in E.164 format; for example, 11118291*90#42.