Explanation/Reference:
Explanation: Rendezvous conferences (also called meet-me, static, or permanent conferences) require endpoints to dial in to a predetermined multipoint resource. These multipoint resources are shared by a number of endpoints and are capable of hosting many conferences at the same time. Because a dedicated device is used to host rendezvous conferences, these conferences can have many more participants than multisite conferences (but not necessarily more than an ad-hoc conference on a dedicated multipoint device).
Reference: http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/srnd/collab09/clb09/confernc.html