All-path bridging: Path exploration as an efficient alternative to path computation in bridging standards

This work is at: IEEE International Conference on Communications: Second Workshop on Telecommunication Standards: From Research to Standards. In Communications Workshops (ICC). Date 9-13 June 2013, Budapest, Hungary.Link-state based routing protocols are dominant in Shortest Path Bridges (IEEE 802.1aq) and also at TRILL (IETF) Rbridges. Both standards propose a hybrid of switch and router adding a link state routing protocol in layer two that computes shortest paths between bridges. Surprisingly, path exploration mechanisms have not yet been considered at standardization bodies, in spite of some outstanding advantages: simplicity,instantaneous path adaptation to traffic load with load adaptive routing and low latency. We have developed All-path, a family of protocols based on simple path exploration mechanisms based on full flooding of a single frame, as an alternative to the "beatentrail" of path computation. Path exploration (either instantaneous or periodical, proactive or reactive) is an efficient alternative to path computation for bridged networks because the processing cost of address learning at bridges from broad cast frames is very low and Ethernet links provide very high link capacity so that the extra packet broad casts do not impact load significantly. Standardization groups should consider the application of path exploration (instantaneous or periodical, proactive or reactive) mechanisms in Audio Video Bridges and ingeneric bridging networks like campus and data centers to find redundant paths, low latency and load distributionThis work was supported in part by grants from Comunidad de Madrid through Project MEDIANET-CM (S-2009/TIC-1468) .Publicad

Evaluating Native Load Distribution of ARP- Path Bridging Protocol in Mesh and Data Center

RP-Path is a simple, low latency, shortest path bridging protocol for campus, enterprise and data center networks. We recently found that this protocol natively distributes the traffic load in networks having redundant paths of similar characteristics. The reason is that every new path between hosts is selected on-demand in a race among ARP Request packet replicas over all available paths: the first arriving replica gets its path selected on the fly. This means a continuous adaptation of new paths to variations on the load at links and bridges. To show this unique load distribution capability and path diversity property we use a number of simulations for complex scenarios, including two different simulators: one flow- based and one packet-based, and two basic topologies: data center and a regular mesh. We also verify this behavior on real hardware on a network of nine ARP-Path NetFPGA switches. The conclusion is that the ARP-Path protocol efficiently distributes traffic via alternative paths at all load levels, provided that multiple paths of similar propagation delays are availableComunidad de Madri