This object specifies the combination of the network type (IP/ATM), virtual circuit type (PVC/SVC) and ATM adaptation layer type (AAL1/AAL2/AAL5) for the connection used in transporting bearer traffic.

ipPvcAal5 (1) - The bearer traffic is transported in IP network, through Permanent Virtual Circuit(PVC) over AAL5 adaptation layer. atmPvcAal2 (2) - The bearer traffic is transported in ATM network, through Permanent Virtual Circuit(PVC) over AAL2 adaptation layer. atmSvcAal2 (3) - The bearer traffic is transported in ATM network, through Switching Virtual Circuit(SVC) over AAL2 adaptation layer. atmSvcAal1 (4) - The bearer traffic is transported in ATM network, through Switching Virtual Circuit(SVC) over AAL1 adaptation layer.

In MGCP, if the call agent specifies the bear traffic type in the local connection options (CRCX request), configuration of this object will have no effect, otherwise the value of this object will be used when media gateway sending CRCX response.