Session boundary controller-SBC

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Session Border controller (SBC) is a standard configuration product for NGN and IMS networks.SBC is generally located between two service provider networks in a peer environment, or between an access network and a backbone network that provides services to residents and enterprise users. Although some SBC only process signaling, most of them process both signaling and media. This type of SBC implements communication between the component that processes the signaling and the component that processes the media stream signaling, which is carried out within the SBC.Some people think that Softswitch will eventually include the edge controller function. However, the functions and core technologies of SoftSwitch and SBC are obviously different, and the different positioning of the network structure eliminates the possibility of "stuffing" the functions of most SBC.

SBC is generally located between the softswitch and the public Internet that controls the VOIP service. It has the following features:

play the role of a network access terminal (NAT) in the network of the service provider to hide the real IP addresses of the network connected users.
when the network is connected, the network structure of the service provider is hidden, such as the number and location of servers.
act as a network firewall when logging on from an interconnected network