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Direct means that nodes are actually within the structure, while indirect means that the nodes sit outside of the links.

xiaowend

Here latency of mesh in worst case should also be O(sqrt(n)).

sjoyner

Direct: Nodes are sitting on a switch in the network. Indirect: Nodes are not on the switches but instead on the edge of the graphs.

unihorn

Question: Should we also consider of bandwidth between nodes here? It is generally an important indicator when discussing about network.

kuity

In addition: Ring, direct, blocking, O(n), O(n)

chaominy

@unihorn: I agree that bisection-bandwidth is also a very important metric.
Bisection-bandwidth:
1. Crossbar O(N)
2. Multi-stage: O(N)
3. Mesh: O(sqrt(n))
4. Ring: O(1)

TeBoring

@chaominy In the answer the TA posted on pizza, the bisection-bandwidth of Mesh is O(N). Which should be correct?

kayvonf

@TeBoring, chaominy: bisection bandwidth of a mesh is O(sqrtN). Think of the number of links cut by a vertical line through the network. If the mesh has N nodes, there are sqrt(N) horizontal links.