The Forwarding on Gates architecture : Flexible placement of QoS functions and states in internetworks
A main driver of Future Internet applications and services is Quality of Service (QoS). Current Internet technologies provide no suitable QoS support for end-to-end connections due to several drawbacks of IntServ and DiffServ. In this article, we propose the “Forwarding on Gates” (FoG) architecture, which answers the QoS questions by the help of a new inter-network architecture. It applies its own new network protocol, which was designed to handle IntServ and DiffServ in an integrated way. FoG supports resource reservations for QoS guarantees in IntServ scenarios and prioritized traffic in DiffServ scenarios as well as a combination of both. As core advantage, the QoS support of FoG works in a scalable way by allowing a network to move QoS states and delegate decisions about the QoS usage to the entities demanding for QoS. This article describes the architecture, its network protocol, and solutions for interoperability with current networks. The evaluation includes theoretical descriptions of network configurations for a use case not supported by IP. Moreover, simulations show that the protocol overhead is comparable to IPv6, although packets can select QoS explicitly. Measured routing graph sizes for various setups show the flexibility of the FoG architecture.