right, its cello switch
multimedia gateway is a bridge between different transport technologies.
when we apply softswitches that is separate the control and payload on different layers. the payload is carried by MGW.AT THE SAME TIME the payload may be coming from different transportation techniques and have to be propagated further on some other transport. for example its coming from PSTN network as TDM and going to 3g subs as ATM.SO media gateway will transform it in appropriate form for its further propogation.
ARSHAD M