the new architecture and uses the virtual service framework. At the time of writing this book, AT&T has deployed initial implementations of some BVoIP services including mobile call recording and AT&T Collaborate, which is described here as a BVoIP use case. AT&T Collaborate is a hosted BVoIP service that is intended to serve all business segments. The customers run the range of small businesses with 1-5 lines or extensions, all the way to large enterprises with thousands of lines and extensions. As shown in Figure 14.22, AT&T Collaborate service elements are deployed in AIC. The DBE is used to provide secure data access to the platform. The session bor- der gateways are used to provide secure SIP access to the platform for voice and video calling. The Collaborate service complex is a grouping of servers that perform service logic, routing, media func- tions, device management, voice messaging, desktop sharing, and supporting services. The complex connects to other carrier networks via SIP interconnect where available and TDM trunking otherwise. The virtual service framework is used to deliver the Collaborate service. Most of the design principles applied to the virtualized IMS service platforms (refer to Section 14.4.1) apply to this service also. The SBC is decomposed into signaling SBC and media SBC. The signaling and media SBC VNFs are reused and instantiated for access and network interconnect purposes. Subscriber data are decoupled from the AS logic. VNF VMs are deployed across multiple cloud availability zones at a site using anti-affinity rules. Many reusable VNFs are added to the VNF catalog with this service, including the signaling SBC, media SBC, DBE, and the media server. The decomposed SBC, media server VNFs, and the ASs included in the Collaborate service complex can be reused for other services. AT&T Collaborate is one of the first virtualized services for which control loop automation using the virtual service control loop framework for auto-recovery of failed VMs is Building the Network of the F