In the evolution of the optical transport network to the packet transport network, one of the main concerns of the operators is the interworkingbetweennetworks.
在光传送网向分组传送网演进的过程中，网络之间的互联互通是运营商关心的主要问题之一。
2
There will be a need for interworking functions (IWF) between ISDN and dedicated networks to cope with the different environments given by the various networks.
为了适应各类网络给出的不同环境，在ISDN和专用网之间将需要互通功能(IWF)。
3
Trunking Media Gateway transmits media stream between IP and circuit switching networks, implements interworking of IP and circuit switching networks with signaling gateway in Softswitch network.