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Re: [ns] Hierarchical addressing and mcast



On Thu, Oct 19, 2000 at 09:35:14AM -0700, Haobo Yu wrote:
> > > I haven't bothered with centralised multicast or BST.
> > 
> > Don't even think of using hierarchical addressing with these two critters
> > either.
> 
> I'm curious in what sense hierarchical routing does not work with
> centralized multicast? I know there is a test in
> test-suite-hier-routing.tcl for centralized multicast.

When I turn on hierarchical addressing, my packets don't get delivered
or replicated. And I start sending packets waaaaay after the tree should
be computed (instantaneous). I've got a fairly unsophisticated topo:


0.0.2             0.1.1              0.2.1
(2)                (3)                (6)
   \                |                /
    ---- (0) ----- (4) ----- (5) ----
   /    0.0.0     0.1.0     0.2.0    \
(1)                                   (7)
0.0.1                                0.2.2

Nodes 1, 2, 3, 6, and 7 join a single mcast group. I've also annotated
the hierarchical addresses (although someone ought to document that
you MUST start addressing from 0...)

Nodes 0, 1, and 2, and 5, 6, and 7 used to be LANs, but I know better
now.

The agents on nodes 1, 2, 3, 6, and 7 are derived from Agent/UDP.

I'd send the patch for the code too, but, it would also contain some
work I'd done to "improve" ns's interaction with dmalloc (as in actually
reporting file and line number of the allocations.)

> This is as far as I know. I don't know how to get hier routing work with
> DM, nor how to get DM work with LAN :(



-scooter