Efficient Distributed Conference Architecture in SIP Environment

SIP 환경에서의 효율적인 분산형 컨퍼런스 구조

  • 조현규 (금오공과대학교 컴퓨터공학과) ;
  • 이기수 (금오공과대학교 컴퓨터공학과) ;
  • 장춘서 (금오공과대학교 컴퓨터공학과)
  • Published : 2008.05.31


The centralized conference architecture, one of the conference architectures in SIP(Session Initiation Protocol) environment, is widely used as it has the advantage of conference management and control. However it has been limited in scalability. Therefore we have proposed an efficient distributed conference architecture to improve scalability of centralized conference model. In our architecture, if the number of conference participants exceeds the predefined maximum number, a new conference server is added to the conference dynamically. In this case, the focus of existing server acts as primary focus and the focus of added server acts as secondary focus, and dynamic reallocation of participants between servers is done to equally divide the loads. This process is repeated as the number of conference participants increases. For this behavior, we have proposed procedure of adding the conference server, SIP call signal exchange, signaling procedure for RTP(Real Time Transport Protocol) sessions between conference servers, and procedure of conference event package between conference servers. The performance of our proposed model is evaluated by experiments.


SIP;Conference;Conference Event Package


  1. J. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston, J. Peterson, R. Sparks, M. Handley, and E. Schooler, "Session Initiation Protocol," RFC 3261, 2002(6).
  2. J. Rosenberg, "A Framework for Conferencing with Session Initiation Protocol(SIP)," RFC 4353, 2006(2).
  3. K. Singh, G. Nair, and H. Schulzrinne, "Centralized conferencing using SIP," in Internet Telephony Workshop 2001, New York, 2001(4).
  4. R. V. Prased, R. Hurni, and H. Jamadagni, "A Scalable Distributed VoIP using SIP," Proc. 8th IEEE ISCC, pp.608-613, 2003(6).
  6. 조현규, 이기수, 장춘서, "SIP 환경에서의 중앙 집중형 컨퍼런스 모델 기반의 새로운 서비스 모델에 관한 연구", 한국콘텐츠학회논문지, 제6권, 제 2호, pp.17-26, 2006.
  7. H. Schulzrinne, S. Casner, R. Frederick, and V. Jacobson, "RTP: A Transport Protocol for Real-Time Applications," RFC 3550, 2003(7).
  8. J. Rosenberg, H. Schulzrinne, and O. Levin, "A Session Initiation Protocol (SIP) Event Package for Conference State," RFC 4575, 2006(8).
  9. R. Sparks, "The Session Initiation Protocol (SIP) Refer Method," RFC 3515, 2003(4).
  10. A. B. Roach, "Session Initiation Protocol (SIP)-Specific Event Notification," RFC 3265, 2002(6).