Ò Ae Blockin Blockin

Internet Appli ations Fugui Wang Computer S ien e and Engineering Department Mi higan State University East Lansing, MI 48824 wangfugu se.msu.edu Prasant Mohapatra Department of Computer S ien e University of California Davis, CA 95616 prasant s.u davis.edu Sarit Mukherjee and Dennis Bushmit h Panasoni Information and Networking Te hnologies Lab Two Resear h Way Prin eton, NJ 08540 fsarit, dbg resear h.panasoni . om Abstra t Di erentiated servi es (Di Serv) was re ently proposed by the IETF as a s alable solution for the Internet QoS. Within the Di Serv ar hite ture, premium servi es is a servi e lass whi h is proposed for intera tive real-time appli ations like Internet telephony or video onferen e. In order to ensure the servi e quality of premium servi es, ea h Di Serv domain need to appropriately negotiate a servi e level agreement(SLA) with its ustomers and neighboring domains. Be ause the resour es for premium servi e is usually a small part of the total network bandwidth, dynami SLA negotiation is preferred to maximize the resour e utilization. However, a ompletely dynami SLA negotiation s heme introdu es s alability problem for the bandwidth broker(BB). In this paper, we introdu e the on ept of \pipe" as a viable solution for this s alability problem. We propose a simple threshold-based updating s heme for the pipe whi h in urs an a eptable updating overhead for the BB while maintaining a high utilization of the pipe. We study the performan e of the threshold-based updating s heme and ompare it with an ideal updating s heme. The ideal s heme is theoreti ally optimal as it uses future knowledge for periodi ally updating the pipe apa ity. The performan e of the threshold-based updating s heme is very lose to the ideal updating s heme.