Mark works as a Voice technologies associate for PassGuide Inc. His company uses Cisco IP phones for its voice network. He wants to use a protocol that can be used for communication between Cisco…

Mark works as a Voice technologies associate for PassGuide Inc. His company uses Cisco IP phones for its voice network. He wants to use a protocol that can be used for communication between Cisco UCM and terminal points. He also wants the protocol to provide a facility to make quick changes to it and add needed features and functionality. Which of the following protocols will he use for the network?