Cisco VGD-1T3, Руководство по настройке программного обеспечения

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Using Cisco Unified Communications Manager to Configure MGCP Gateway Support
Configuring MGCP Gateway Support
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Cisco VGD 1T3 Voice Gateway Software Configuration Guide
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MGCP gateway fallback support—All active MGCP analog and T1 CAS calls are maintained during
the fallback transition. Callers are unaware of the fallback transition, and the active MGCP calls are
cleared only when the communicating callers hang up. Active MGCP PRI backhaul calls are
released during fallback.
Any transient MGCP calls (that is, calls that are not in the connected state) are cleared at the onset
of the fallback transition and must be attempted again later.
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Basic connection services in fallback mode—Provides basic connection services for IP telephony
traffic that passes through the gateway. When the local MGCP gateway transitions into fallback
mode, the default H.323 session application assumes responsibility for handling new calls. Only
basic two-party voice calls are supported during the fallback period.
Except for ISDN T1 PRI calls, all the MGCP calls that are active at the time of fallback are
preserved, but transient calls are released. When a user completes (hangs up) an active MGCP call,
the MGCP application handles the on-hook event and clears all call resources.
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Rehome support—Provides a rehome function in the gateway fallback mode that detects the
restoration of a WAN TCP connection to the primary Cisco Unified Communications Manager
server.
When the fallback mode is in effect, the affected MGCP gateway repeatedly tries to open a TCP
connection to a Cisco Unified Communications Manager server in the prioritized list of call agents.
This process continues until one of the Cisco Unified Communications Manager servers in the
prioritized list responds.
The TCP open request from the MGCP gateway is honored, and the gateway reverts to MGCP mode.
The gateway sends a Restart-in-Progress (RSIP) message to begin registration with the responding
Cisco Unified Communications Manager.
All currently active calls that are initiated and set up during the fallback period are maintained by
the default H.323 session application, except ISDN T1 PRI calls. Transient calls are released. After
rehome occurs, the new Cisco Unified Communications Manager assumes responsibility for
controlling new IP telephony activity.
The following types of interfaces on the gateway are supported:
• FXS analog interfaces—For connecting to the PSTN or analog phones
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FXO analog interfaces—For connecting to the PSTN or PBXs
• T1 CAS digital interfaces—For connecting to the PSTN or PBXs
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T1 PRI digital interfaces—For connecting to PBXs and central offices (COs)
MGCP Gateway Registration with Cisco Unified Communications Manager
Table 1 describes what can happen when either the gateway loses connection to the primary
Cisco Unified Communications Manager or the gateway also loses connection to all backup
Cisco Unified Communications Manager servers.