On Jul 1, 2008, at 9:09 AM, Freek Dijkstra wrote:
John Vollbrecht wrote:
Attached is a DCN glossary which is part of DCN architecture and DCN reservation documents.
Thanks John!
path - a connection between a source and destination. A path is a sequence of hops.
I would argue that a path is a sequence of edges/links rather than hops. That way I can distinguish between two links between the same hops, and can more easily between different types of relations between hops (link, cross connect, adaptation, de-adaptation)
I think of a path a a sequence of hops because a requested path may contain some but not all intermediate hops, and hops may be domains rather than links. A strict path is a sequence of links. There may be multiple paths between hops but paths may be "potential" or requested as well as confirmed and strict. What I think is needed is a concept of resources like bw that are included in a connection or circuit. I have (I think wrongly) been using path to describe a circuit, which is path with specific resources in each segment of the path. Probably we need a name for this concept of circuit over time. Perhaps just circuit is good enough -- what do you think. Then what DCN reserves is a circuit and its circuit segments. Paths and path segments are similar without resources assigned to them. does this make sense? In that case, adaptations are assigned to circuits rather than links. Which is not to say that circuits cannot be links in a different infrastructure of higher order links and nodes. John
Regards, Freek
John Vollbrecht, Senior Network Engineer Internet2 office +1-734-352-4960 | mobile +1-734-395-7890