Isochronets: A High-speed Network Switching Architecture

Florissi, Danilo

Traditional network architectures present two main limitations when applied to High- Speed Networks (HSNs): they do not scale with link speeds and they do not adequately support the Quality of Service (QoS) needs of high-performance applications. This thesis introduces the Isochronets architecture that overcomes both limitations. Isochronets view frame motions over links in analogy to motions on roads. In the latter, traffic lights can synchronize to create green waves of uninterrupted motion. Isochronets accomplish similar uninterrupted motion by periodically configuring network switches to create end-to-end routes in the network. Frames flow along these routes with no required header processing at intermediate switches. Isochronets offer several advantages. First, they are scaleable with respect to transmission speeds. Switches merely configure routes on a time scale that is significantly longer than and independent of the average frame transmission time. Isochronets do not require frame processing and thus avoid conversions from optical to electronic representations. They admit efficient optical transmissions under electronically controlled switches. Second, Isochronets ensure QoS for high-performance applications in terms of latency, jitter, loss, and other service qualities. Isochronet switches can give priority to frames arriving from selected links. At one extreme, they may give a source the right-of-way to the destination by assigning priority to all links in its path. Additionally, other sources may still transmit at lower priority. At the other extreme, they may give no priority to sources and frames en route to the same destination contend for intermediate links. In between, Isochronets can accomplish a myriad of priority allocations with diverse QoS. Third, Isochronets can support multiple protocols without adaptation between different frame structures. End nodes view the network as a media access layer that accepts frames of arbitrary structure. The main contributions of this thesis are: Design of the Isochronets architecture. Design and implementation of a gigabit per second Isochronet switch (Isoswitch). Definition of the Loosely-synchronous Transfer Mode (LTM) and the Synchronous Protocol Stack (SPS) that add synchronous and isochronous services to any existing protocol stack. Performance evaluation of Isochronets.



More About This Work

Academic Units
Computer Science
Department of Computer Science, Columbia University
Columbia University Computer Science Technical Reports, CUCS-021-95
Published Here
February 10, 2012