# vmsamp environment

The following illustration shows the environment in which the vmsamp functions. For clarity, the illustration shows the 3G-324M Interface and the Video Messaging Server Interface operating on independent boards. However, both interfaces can reside on the same CG board.

Natural Access services control and configure the gateway and server components except for the H.245 stack that runs on the host outside of Natural Access.

The H.324M Middleware abstracts the H.245 stack to negotiate session control with remote wireless devices using an H.223 multiplexer as the data link layer of the transport mechanism.

For demonstration purposes, PRI call control is achieved using Q.931 signaling by the onboard ISDN stack. TDM trunk connections are created using the H.110 bus on the CG board and are managed by the Natural Access Switching service. For more information, refer to the Switching Service Developer's Reference Manual.