As a part of the conference control in Multimedia Conferencing Systems(MCS)
floor control is used to coordinate the access to the shared resources among the participants
which has a direct bearing upon the QoS of the system.In this paper
the floor control in SIP-based MCS is realized in the architecture of JAIN SIP by using the scalability of the Session Initiation Protocol(SIP)
which is characteristic of diversity in the way of control and adaptability to distributed systems.The test results show that the system design is rational and the delay is tolerable.