Application Layer Multimedia Multipoint Conferences Using Megaco/H.248

• Main Authors: Jen-Chun Chang, 張任君
• Other Authors: Wanjiun Liao
• Format: Others
• Language: en_US
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/69568952416437598908

碩士 === 國立臺灣大學 === 電機工程學研究所 === 89 === This paper proposes a new approach to establishing application layer conference trees for multimedia multipoint conferences on the Internet using the Megaco/H.248 protocol, a VoIP media gateway control protocol. Traditionally, a multipoint conference takes place through an MCU, which centralizes the control of the conference. This approach requires each conference member have a direct connection to the MCU, thus forming a star topology for the conference. The proposed approach establishes a shared, cost effective conference tree for the conference. The tree is rooted at the conference initiator, who initiates the conference, and spans over all the conference members. The tree branches grow or are trimmed dynamically and adaptively, in a way to avoid the growth of a skewed tree. Data destined to the conference goes to the tree in one copy directly from the branch of which the sender is located. I have developed a simplified analytical model and conducted simulations to compare the performance of the proposed approach with other approaches. The results show that our approach enjoys the advantage of lower join latency and better bandwidth efficiency as compared to the traditional MCU approach and is also cost effective.