[Csci551-talk] some thoughts about TA's sample implemenation

[Affan, Syed]

-----Original Message-----
From: csci551-talk-bounces at mailman.isi.edu
[mailto:csci551-talk-bounces at mailman.isi.edu] On Behalf Of hua liu
Sent: Friday, April 22, 2005 12:15 PM
To: csci551-talk at mailman.isi.edu
Subject: [Csci551-talk] some thoughts about TA's sample implemenation


Hi,

I compared my implementation and TA's sample implmentation of ProjA and
had some questions in TA's code. Here are my thoughts:

1. What if node A is in e_SegUpdate or in e_FileXchange and now a new
node B  joins in. Node B will send tracker a GROUP_SHOW_INTEREST, and
tracker will send GROUP_ASSIGN to node A and node B. In TA's code, on
reception of GROUP_ASSIGN, node A will generate an error message. But is
this actually an error?
> I don't get it, why would A receive the GROUP_ASSIGN? The new node B
receives that and he should be in e_TrackerSent state. There is no need
for tracker to send gratuitous group assignments.


2. In TA's code, a node can only start next round of download when the
ReqTOTimer expires. That means, even there are no loss in CLNT_SEG_REP,
a node must wait timeout to send next GROUP_SHOW_INTEREST. But I think a
node should start next round of downloading immediately after it gets
all the CLNT_SEG_REP. It should only wait for a timeout if some
CLNT_SEG_REPs are lost. 
> That might be overlooked but can be easily taken care of, and if oyu
want to use it, it would be good that you do implement this. 

Correct me if I am wrong. I am wondering how do we handle the first
case. Can we just ignore the GROUP_ASSIGN if we are not in
e_TrackerSent? 

Thanks!
Hua