[brite-users] Re: Huge node sets and Dijkstra's SP algorithm
Thu Feb 20 11:18:01 2003
I am cross-posting this to the brite-users@ list as others have asked this
question to me also.
To answer your questions:
> - RT_NODE regular host node within AS
> - RT_BORDER router node in AS
> - E_RT - intra AS edge
> - E_AS - router level edge
Yes, you're correct.
More precisely, RT_BORDER stands for a border router in an AS. That is,
it is a router in AS A which has neighbors that fall in other ASes.
Also, E_AS stands for an inter-AS edge, i.e. an edge that connects two
ASes, or equivalently, two border routers belonging to two different ASes.
> I assume that I can specify how many routers I want per AS? And also that
> I dont want any AS-AS edges that do not go through routers, i.e only
> router edges can connect two different AS's.? I think I've read this in
Yes, you can specify the number of routers per AS.
If you decide to do this, you may want to use the
BottomUpHierModel. This model does the following: first, it
generates a single-level router topology. Second, it groups routers
into AS boundaries until a specified threshold (size) is reached.
You could also easily extend the TopDownHierModel so that it generates a
router level topology for each AS of the size you desire. I think that
right now TopDownHierModel generates fixed size router topologies for each
AS (clearly not realistic, but it was intended to be a dummy model that
others would extend).
I would also suggest you take a peek at Tangmunarunkit et al's CCR
paper: Does Size Determine AS Degree. In this paper they found that they
number of routers corresponding to an AS (its size) follows a heavy tailed
distribution. Another suggestion would be to use rocketfuel
traces for your router level topologies.