On Dec 16, 2009, at 9:12 AM, Aaron Brown wrote:
A question still open is the definition of "connected"? Is it a literal connected graph, or does it mean connected such that folks could actually somehow make circuits to get from any point in the graph to any other point (ignoring how they know that reservations and the like can happen)?
This is a good question. In my mind being able to make circuits (or connections) implies that there is an encapsulation and "concatenation" capability at all points on the graph.
For example, say someone has a switch with sonet ports and ethernet ports and that switch connects to two other nodes, one via ethernet and one via sonet. Is the implication that the node connected via ethernet can connected to the node connected by SONET? If not, is that a connected graph for these purposes, or are there two separate topologies (the SONET one and the Ethernet one)?
I wonder if there needs to be a concept of "topology at a layer", where layer is a particular technology layer.
Relatedly, if a topology is disjoint due to solely to switching capabilities instead of cabling, is that two separate topologies or a single topology? I am not sure what you mean by this -- how would switching capabilities make something disjoint?
John