IP network performance and QoS: signaling and interworking issues

In 2000, the IAB's RFC 2990, "Next Steps for the IP QoS Architecture", compared IntServ and DiffServ style networks and considered broader architectural approaches/requirements, including: critical "gaps" in routing; resource management; monitoring and accounting; application and service development; incremental, heterogeneous deployment. Therefore, what is needed is "a set of QoS mechanisms and a number of ways these mechanisms can be configured to interoperate in a stable and consistent fashion". The paper considers the present state of end-to-end (E2E) IP QoS and progress still to be made. Y.1541 specs exist for NI-to-NI (network interface) IP QoS classes, but there is no widely accepted delivery mechanism yet. It is still unclear if QoS-related resource control of others' networks will ever be allowed; even if some carriers agree, interoperability is still an issue. Over-provisioning is still central to many solutions. No forum is yet addressing reliability and restoration mechanisms for E2E IP QoS in any tangible way. Recent attention on IP emergency communications have served as a magnet for all of the shortcomings of E2E QoS proposals in IP space (IETF's IEPREP).