RE: [ns] using SRM

[Sencun Zhu <szhu1@ise.gmu.edu>]

thank you for your reply, I have another thing not very clear. To me it is
a little strange to use SRM in tcl level, usually in multicast
application, the sender has:

$srm(0) set dst_addr_ $group
$srm(0) set dst_port_ 0

to my best understanding, the receiver should call:

$ns join-group $rcvagent(0) $group

to join the group and receive data.but in the
example: /tcl/ex/srm-chain.tcl or other srm application, I did not find
the receivers call the sentence above, instead, the receivers also have:

$srm(1) set dst_addr_ $group
....


I wonder how can the receiveing srm agents get data???


thank you again.


Sencun

On Tue, 11 Jul 2000, Haobo Yu wrote:

> 
> >         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
> 
>