As we discussed in our recent article "What is TRILL?," with the tremendous growth in data centers and the seemingly eventual move to all things being Ethernet-based, the limitations of STP and the complications caused by working around those limitations, especially in a virtualized environment, are beginning to impact data center agility. Ideally, the entire network would be a flat, single network, but the limitations of spanning tree protocol (STP) won't allow that to happen. Currently, most networks have to be carefully designed to work around STP's limitations, which leads to a mix of Layer 2 and Layer 3 network infrastructures.
There seems to be a consensus among the major network players that Transparent Interconnection Of Lots of Links, (TRILL), is the logical replacement for STP. If so, this is going to require a change in the network infrastructure. I am reminded of the days when Novell NetWare introduced the concepts of directory services, which required a redesign of the networking infrastructure. It had to happen, and if you were going to do it, you might as well look at what Microsoft and others had to offer.
I think the same will be true as we move out of STP and into flat layer 2 networking. If you are going to have to gradually begin to replace your current network infrastructure gear, it probably makes sense to see what the competitors in the space have to offer. Many transitions start by borrowing sound technologies in adjacent markets and implementing them. TRILL, for example, borrows the idea of a multi-pathing fabric from FC SANs, which is taking root as the for equal-cost, multi-pathing for Ethernet, essentially, an "Ethernet Fabric." Also, while TRILL will be the standard, it will potentially be just the starting point for each of these vendors, and they may each add individual capabilities to their products that may make their switches more compelling than someone else's. While this can create some compatibility concerns, the feature set may be so compelling that it outweighs those concerns. Worst case, just like SANs today, you will probably be able to switch back to a compatibility mode.
The point is that TRILL will be a flashpoint that provides an opportunity for users to broadly consider other competitors to the market leader. With these types of changes on the horizon, it is going to be a change filled several years in networking. When we are done with implementing the new infrastructures it will be interesting to see what logos remain.