Internet-Router Buffered Crossbars Based on Networks on Chip

—The scalability and performance of the Internet depends critically on the performance of its packet switches. Current packet switches are based on single-hop crossbar fabrics, with line cards that use virtual output-queueing to reduce head-of-line blocking. In this paper we propose to use a multi-hop network on a chip (NOC) as the crossbar fabric, with FIFO-queued line cards. The use of a multi-hop crossbar fabric has several advantages. 1) Speed-up, i.e. the crossbar fabric can operate faster because NOC inter-router wires are shorter than those in a single-hop crossbar, and because arbitration is distributed instead of centralised. 2) Load balancing because paths from different input-output port pairs share the same router buffers, unlike the internal buffers of buffered crossbar fabric that are dedicated to a single inputoutput pair. 3) Path diversity allows traffic from an input port to follow different paths to its destination output port. This results in further load balancin...

• Type: Conference
• Year: 2009
• Where: DSD
• Authors: Kees Goossens, Lotfi Mhamdi, Iria Varela Senin
• Keywords: Crossbar Fabric, DSD 2009, Hardware, Line Cards, Single-hop Crossbar