Measurement-Based Admission Control at Edge Routers

Abstract

Abstract-It is very important to allocate and manage resources for multimedia traffic flows with real-time performance requirements in order to guarantee quality-of-service (QoS). In this paper, we develop a scalable architecture and an algorithm for admission control of real-time flows. Since individual management of each traffic flow on each transit router can cause a fundamental scalability problem in both data and control planes, we consider that each flow is classified at the ingress router and data traffic is aggregated according to the class inside the core network as in a DiffServ framework. In our approach, admission decision is made for each flow at the edge (ingress) routers, but it is scalable because per-flow states are not maintained and the admission algorithm is simple. In the proposed admission control scheme, an admissible bandwidth, which is defined as the maximum rate of a flow that can be accommodated additionally while satisfying the delay performance requirements for both existing and new flows, is calculated based on the available bandwidth measured by edge routers. The admissible bandwidth is a threshold for admission control, and thus, it is very important to accurately estimate the admissible bandwidth. The performance of the proposed algorithm is evaluated by taking a set of simulation experiments using bursty traffic flows.

A cross traffic estimate method for high speed networks

“…This is mainly because of the buffer size's ignoring of [10]. Reference [10] also exhibits its intrusion (exceed bottleneck capability under almost every conditions) in Fig. 11.…”

“…From Fig.10 and Fig.11 we can see that our scheme has similar accuracy as minimal backlogging at lower cross traffic level but an evident advantage when the network is heavily loaded. This is mainly because of the buffer size's ignoring of [10]. Reference [10] also exhibits its intrusion (exceed bottleneck capability under almost every conditions) in Fig.…”

“…This assumption has already been used in previous works and be verified appropriate [9] [10]. It can be seen as a series queues connected each other if multiple bottlenecks exist.…”

“…Minimal backlogging algorithm proposed by [10] is also based on M/G/1 model. Our simulation also implements it in order to show its difference from our method.…”

“…Both algorithms mentioned above employ moment based means, so they need much large samples and relatively long period to obtain stable result and much intrusive. Reference [10] proposes an estimator based on M/G/1 model through a probing means named minimal-backlogging method. It does not make any assumption about the router's processing time and is more appropriate for optical networks than the previous two.…”