Only suited to simple switch fabrics Very limited inter-switch bandwidth No resilience to failures
• Ring
Only suited to simple fabrics Very limited inter-switch bandwidth Provides limited resilience to failures
• Full Mesh (1 or more ISLs between all switches)
Suited to small 4, 5, 6 switch fabrics Larger inter-switch bandwidth than ring But more ports used
• Core-Edge
More scalable solution for large fabrics May be spare “core” switch ports available Each switch should have at least 2 ISLs to core
There are a number of different configurations we can use to create a fabric.
Here we consider the choices available, and which to choose for a particular application.
• Cascade o Best suited for fabrics with low switch counts, or where there are “islands” of connectivity with little need for “symmetrical” or “any- any” bandwidth between islands.
• Full Mesh (or Partial Mesh)
o Best suited to fabrics with low switch counts where there is a need for high inter-switch connectivity. However, this topology does not scale well beyond a few switches.
• Core-Edge o Best topology for very large fabrics, with high switch count.