Cisco Unified Communications Release 5.1(1) testing for IP telephony was designed to test the hardware and software components that work together in a multi-site distributed IP telephony deployment. For this testing, several site models were created. Each site model was designed to test a specific set of features and interactions. For information about the components, configurations, and environment tested in Cisco Unified Communications Release 5.1(1), see Tested Deployments and Site Models. 