In a recent newsletter we mentioned the fact that we are driving a series of monthly discussions on the evolution of data center LANs and are including in those discussions six of the leading vendors: Arista, Avaya, Brocade, Cisco, Extreme and HP. The August discussion topic is the best alternative to the spanning tree protocol (STP). We will use this newsletter to summarize some of the discussion.
There was uniform agreement among the vendors that IT organizations should move away from STP. That, however, was about the only topic on which all of the vendors agreed. There was a degree of agreement among the vendors that Multi System Link Aggregation (MLAG) was a good replacement for STP. That said, each vendor's implementation of MLAG is proprietary. So, while the vendors agree in concept about the value of MLAG, they don't agree about how it should be implemented. In addition, some vendors, such as Extreme Networks, view MLAG as potentially a long-term solution. Most of the other vendors, view it as potentially more of a short to midterm solution until one of a couple of standards-based solutions are available.
The two most often discussed alternatives to STP are Shortest Path Bridging (SPB) and Transparent Interconnect of Lots of Links (TRILL). HP is an example of a vendor that appears to be equally committed to both alternatives. In the August discussion, HP states that it is committed to supporting standards and will adopt those standards as they make the most sense for our customers. HP also stated that they are actively working on TRILL based solutions for the traditional Enterprise customer segment, including open standards participation with the IETF and that they will start to release TRILL compliant products in 2H 2011. HP added that it was evolving some of its existing technology to current standards such as SPB.
While Avaya, Cisco and Brocade may well end up supporting both SPB and TRILL, in the August discussion each vendor expressed a clear preference. For Avaya that was SPB, and for both Cisco and Brocade it was TRILL.
We are going to keep going with the discussion of the best alternative to the spanning tree algorithm until Sept. 7. The discussion topic for September is the convergence of the LAN and the SAN. You can read more of what the vendors have to say about that both topics here.