Which of the following statements is true regarding ad-hoc conferences without Cisco VCS?

A.
SIP endpoints can neither initiate nor be added to an ad-hoc conference.

B.
SIP endpoints cannot initiate an ad-hoc conference but can be added to an ad-hoc conference.

C.
SIP endpoints can initiate an ad-hoc conference but cannot be added to an ad-hoc conference.

D.
SIP endpoints can initiate an ad-hoc conference and can be added to an ad-hoc conference.

Explanation:
Session Initiation Protocol (SIP) endpoints without Cisco TelePresence Video Communication Server (VCS)
can initiate an ad-hoc conference and can be added to an ad-hoc conference. Ad-hoc conferences are also
known as unscheduled or on-demand conferences. To participate in an ad-hoc conference, simply press the
Conf, Join, cBarge, or Add keys on the endpoint.
H.323 endpoints without Cisco VCS cannot initiate an ad-hoc conference but can be added to an ad-hoc
conference. A SIP endpoint is required to add an H.323 endpoint to an ad-hoc conference. H.323 endpoints
can initiate an ad-hoc conference by using Multiway with Cisco VCS.
Either MultiSite or Multiway can be used for ad-hoc conferences, which are also called on-demand
conferences. MultiSite uses a phone’s native multipoint control unit (MCU) functionality and allows up to four
participants in a conference. However, MultiSite requires that an option key be installed on each endpoint.
Multiway allows many more participants but requires a Cisco VCS and a Cisco TelePresence MCU to handle
the conference. In addition, an option key is not required for Multiway. MultiSite and Multiway are mutually
exclusive; if Multiway is used on your network, you should disable MultiSite on the endpoints.

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