The SBC (Session Border Controller) allows the branch offices to have their own addressing scheme, independent of the addressing scheme of the data center or other branch offices.
If one must pass through the internet to get from the data center to the branch office, then often the addressing space of the data center is extended to the branch office by creating a VPN tunnel between the data center and the SBC in the branch office. In this scenario there is no central media relay SBC, media connections for inter-branch calls are made directly between branches.
Currently the Branch SBC or Comdasys SBC is supported as a branch SBC. These SBCs combine branch survivability and SBC functionality in the same box as well as NAT (Network Address Translation) traversal, firewall pinholing, and (limited) topology hiding for the branch. When VPNs are used between the branch and the data center the Comdasys SBC can be used to terminate the VPNs in the branch and provide dynamic switchover to a secondary VPN if primary VPN fails (in a scenario with geographic separation of Lotus Sametime Unified Telephony nodes).
Parent topic: SBC (Session Border Controller)