RE: [ns] using SRM

["Haobo Yu" <haoboy@isi.edu>]

>         In ns manual, there is a chapter about webcache and send real
> data. the one based on Tcp is very tricky, since it uses call back
> function to get data from the sender,however, as far as I know, this only
> applies to one-to-one connection. I am think if we can have a global
> linked list to store the sent data, and the receiver can get data from
> this list directly. while every element in the list keeps a counter
> recording how many potential receivers it has, when a receiver get one
> copy, just decrease the counter , and the last one free the buffer, so
> that this way can apply to one -to -many case.

You can in fact put your data in individual SRM packets (after the session
data). This makes sense if you don't want to do fragmentation and
reassembly; in the SRM context this is not a problem because you are
supposed
to send ADUs in each SRM packets.

>      I am doing SRM to send real data, one way to do is like udp , but I
> think maybe it is better  if the method above can work, then
> I have to know in-fly how many members in a group, is it possible?

If you want to do it the other way, you can certainly know how many
members are in a group, because SRM exchanges those session messages
and it has to keep a distance array among members. I think you can
find this info in some variable in the otcl part.

- Haobo