CHAPTER 1. Voice Feature308 © SAMSUNG Electronics Co., Ltd.Operation ModeWhen the Ubigate iBG2016 runs as SIP gateway, it can work in an CallManager Interworking mode where it interworks with SIP network via CallManager, or in a Stand-alone Mode(or Toll Bypass Mode) where it directlyinterworks with other SIP gateway with Call Manager. If it runs in an CallManager Interworking Mode, and when Call Manager fails, it is automaticallychanged to a Survivable Telephony Mode to provide a basic function withoutCall Manager. Each operation mode is described below.Call Manager Interworking ModeIn an Call Manager Interworking Mode, the Ubigate iBG2016 is registered inCall Manager using a REGISTER method to perform operation. Call Managermanages multiple IP phones and Ubigate iBG2016s. Generally, the UbigateiBG2016 delivers the calls to be routed to SIP to Call Manager. Call Managermakes a decision on actual routing to route a call to other Ubigate iBG2016,IP Phone or other Call Manager.The generic network configuration in Call Manager Interworking Mode isshown in the Figure 26.1, Figure 26.2 shows the configuration-a single CallManager exists in a headquarter office to control the corporate VoIP network,and multiple Ubigate iBG2016s exists in individual branch offices. In addition,multiple IP phones exist in headquarter and each branch. All the gateways andIP phone in a company are registered in Call Manager, and Call Managercontrols the overall routing of the internal and external calls.Under this configuration, the Ubigate iBG2016 performs the internal and finecontrol of itself, but it is controlled by Call Manager from the perspective ofthe entire networks since it is a device subject to Call Manager.
