| It is increasingly important to provide system support for networking with quality of service (QoS) guarantees. This trend is in part due to the emergence of distributed multimedia applications having real-time constraints. At the network level, it has been shown that end-to-end QoS (such as throughput and delay) guarantees can be provided by rate-based packet scheduling together with admission control. In addition, several standardization efforts, such as IPv6 and RSVP, are in progress to avail user applications of access to reserved network resources. However, to deliver truly superior performance to applications running in general purpose workstations, the network-level guarantees must be extended to the operating systems (OS) of these workstations. Towards this goal, we propose an end system architecture with the following major components: (1) adaptive rate-controlled CPU scheduling, (2) an implementation framework of Migrating Sockets for user level protocols, and (3) a constant overhead active demultiplexing mechanism. Besides suitable for networking with QoS guarantees, our end system architecture has other advantages, namely efficiency, flexibility and backward compatibility with existing systems. |
