Sameh Rabie

Quality of service for Internet traffic over ATM service categories

Connecting enterprise sites requires innovative architectures. Virtual private networks (VPNs) linking different organizational sites over the Internet are a popular solution. Internet traffic, however, is rapidly growing and becoming increasingly diverse. There is a strong need for quality of service (QoS) support in the Internet. Asynchronous transfer mode (ATM) backbones supporting QoS are already widely deployed in carrier networks. ATM offers a number of service categories. Each of the ATM services has its merits and limitations, so a tradeoff is necessary in selecting the service category for carrying Internet traffic between enterprise sites. In this paper, we compare the ATM service categories in terms of cost, buffer requirements, and performance with Internet traffic. We find that the ATM available bit rate (ABR) service provides a good synergy with the emerging Internet technologies for supporting end-to-end QoS. Connecting enterprise networks by ABR virtual path connections can guarantee quality of service and minimize queuing delay and loss in the backbone. In addition, it provides flexibility in supporting various implementations at the edge devices.