Cisco^® Certified Design Associate (CCDA) Certification Practice Questions

Exam: 200-310

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Q7. Which one of the following is a Cisco proprietary client/server signalling protocol for call set-up and control?

Correct Answer: B

Explanation:

Q.931 is a standard for call signalling used by H.323 within the context of H.225. 

H.245 specifies messages for opening and closing channels for media streams and other commands, requests, and indications. It is a control channel protocol.H.323 is a standard published by the ITU that works as a framework document for multimedia protocols, including voice, video, and data conferencing, for use over packet switched networks. 

MGCP is a client/server signalling protocol that is used to allow centralized call processing agents (such as CUCM) to control gateways in VoIP networks. MGCP is defined in RFC 3661. In VoIP, RTP transports audio streams. RTP is a transport layer protocol that carries digitised voice in its payload. 

RTP was initially defined in RFC 1889 and the current RFC is 3550. RTP runs over UDP SCCP is a Cisco proprietary client/server signalling protocol for call set-up and control. 

SCCP runs over TCP. SCCP is called a skinny protocol because it uses less overhead than the call set-up protocols used by H.323. IP phones typically use SCCP to register with CUCM and to establish calls.

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