All-path and Torii-HLMAC: beyond link-state routing protocols in shortest path bridges for campus and data center networks

20 Feb

Elisa Rojas. Introduction by Guillermo Ibáñez. University of Alcalá de Henares, Madrid, Spain

External Presentation (External Speaker)

The dominant paradigm in both IETF and IEEE 802.1 standards for shortest path bridges is based on link-state routing in layer two. This results on hybrid devices of router and switch.

At GIST-Netserv research group of University of Alcala de Henare (UAH), we explore simpler and efficient protocols not based on path computation. Two different approaches are presented in the talk.

In the first part of the talk we present All-path bridges, a new family of switching protocols based on simultaneous exploration of all paths and selection of the fastest one (or ones, to set up a multicast tree).

ARP-Path is the first protocol, which upon arrival of a new flow to the network, selects the fastest path by snooping the ARP protocol dialog (request and reply messages).

With the same principle, two new types of All-Path protocols evolve from ARP-Path: Flow-Path and Bridge-Path, flow-based and bridge-based respectively, instead of source address-based.

While preserving the main advantages of ARP-Path: zero configuration shortest path bridging exploiting the full network topology, Flow-Path has the advantages of full independence of flows at the time of path creation and guarantees path symmetry (congruency) and increased path diversity, and Bridge-Path increases scalability by reducing forwarding table entries at core bridges. Among their advantages are: simplicity, instantaneous load adaptive routing and low latency. We present their evaluation and implementation experiences on multiple platforms: Linux, Openflow, NetFPGA.

Basic principle: In the second part, we present summarily Torii-HLMAC, a protocol based on topological address routing. Torii-HLMAC is a multiple-tree hierarchical bridging protocol well suited for fat trees in data centers.

Torii-HLMAC is a scalable, fault-tolerant, zero-configuration data center network fabric architecture protocol as a fully distributed alternative to PortLand for similar multiple tree or classic fat tree network topologies.

It uses multiple, fixed, tree-based positional MAC addresses for multiple path and table-free forwarding. Addresses are assigned by a simple extension of the Rapid Spanning Tree Protocol.

Torii-HLMAC enhances the PortLand protocol advantages of scalability, zero configuration and high performance and adds instant path recovery, fully distributed routing and address assignment.

ARP Proxies may be used to prevent ARP broadcast messages.

This event will be conducted in English


  • Location: Sala 4.1.E05, Edificio Torres Quevedo, UC3M, Avda. Universidad, 30, 28911 Leganes – Madrid

  • Organization: NETCOM Research Group (Telematics Engineering Department, UC3M); IMDEA Networks Institute
  • Time: 01:30 pm