[ns] Building a multicast protocol with dynamic groups

[Will Shaver <will@digitalfountain.com>]

	I'm working on building a new multicast protocol, and have figured out
most of what needs to happen (How to do different packet headers, build
the agents, and the different timers etc.) But I can't find in the docs
(perhaps because it isn't there.) is how to mess with groups. The basic
problem is that in this protocol there 20 or so different multicast
groups sending different data at different rates etc. How do I decare
and use a group in C++. I'd like to be able to have one 'server' agent
and one 'client' agent that manage the different groups and I have to
use C++ as I'm sending information in the actual packets. . . Anyone
know (or know where to look) about Multicast Groups in C++?

...

	Another question, I noticed that the allocpacket methods in packet fill
the packet with garbage data as a payload. if I want say a 100 byte
packet, do I need to alloc 75 and thus account for say a 25 byte header,
or do the headers not actually weigh anything or what? Does actual byte
size in the header (int, double, short etc) show how much is actually in
the header of each packet?

Thanks..

 -Will