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The Cisco 1700, 2600, 2800, 3700, and 3800 series voice gateway routers can communicate with the Cisco CallManager through H.323 or the Media Gateway Control Protocol (MGCP). In H.323 mode, Cisco CallManager does not need to know which particular network module, Cisco Unity Express Advanced Integration Module (AIM), or platform is used. Therefore, once Cisco CallManager supports a particular protocol or feature, this is sufficient for operation.
But in the case of MGCP, there are certain restrictions because some of the voice gateway routers are not compatible with all versions of Cisco CallManager.
To check whether the router is compatible with Cisco CallManager in the MGCP mode, refer to Cisco Voice Gateway Router Interoperability with CallManager.
The Cisco 1700, 2600, 2800, 3700, and 3800 series voice gateway routers can communicate with the Cisco CallManager through H.323 or the Media Gateway Control Protocol (MGCP). In H.323 mode, Cisco CallManager does not need to know which particular network module, Cisco Unity Express Advanced Integration Module (AIM), or platform is used. Therefore, once Cisco CallManager supports a particular protocol or feature, this is sufficient for operation.
But in the case of MGCP, there are certain restrictions because some of the voice gateway routers are not compatible with all versions of Cisco CallManager.