Ah, I see now. I believe this might explain it furthermore.
Each transmission in 802.11 world has a certain number of retries. 
802.11 does not define in its MAC layer that how many retries are
allowed before link is dropped. 
Alas, TCP/IP layer does! I believe it is set to 2 seconds
for the TCP/IP layer (not quite sure about that).

What this means is that as your distance gets bigger you have 
more retries (because of signal fading, errors, etc.) and at 
some points TCP/IP gives up and severs the connection (times out).

The sliding frame and frame size might still have something to do 
with some of the problems, but I believe that retries are more significant
in this case.

-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf
Of Towers, Derek
Sent: Monday, March 29, 2004 11:23 AM
To: '[EMAIL PROTECTED]'
Subject: [BAWUG] RE: Distance vs. Packet Size


Sorry for being unclear about the distance part. It appears there is 
correlation between the distance and the size of the packet that this
phenomonon occurs. The further apart the sites are the smaller the packet
size that this occurs. For example at 1/4 mile say 2x-1 time and at
1 mile its the x-1 time. These numbers are just for reference for
understanding
this phenomonon.

Dont the window size and sliding frame self adjust/negotiate?



-----Original Message-----
From: Ivan Bojer [mailto:[EMAIL PROTECTED]
Sent: Monday, March 29, 2004 11:14 AM
To: Towers, Derek; [EMAIL PROTECTED]
Subject: RE: [BAWUG] Distance vs. Packet Size


It is a little bit unclear to me what are you asking.
I am not sure what do you mean by "distance?" 

If I am understanding you right you might want to look 
at TCP window size and TCP sliding frame for this particular problem.

-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf
Of Towers, Derek
Sent: Monday, March 29, 2004 7:12 AM
To: '[EMAIL PROTECTED]'
Subject: [BAWUG] Distance vs. Packet Size


I have seen this in more than one occasion, using different equipment.
A ping packet with a 32 byte size will last for x time
A ping packet with a 64 byte size will last for x-1 time
A ping packet with a 200 byte size will last for x-2 time
A ping packet with a 500 byte size will last for x-3 time, etc
until at some point it is request timed out from the first packet.

Once any of these sized packet pings start timing out, if I reduce
the packet size it will almost immediately return to responding.

Any one else have this experiece? Know why it is or where I can
find any info on it?

Derek Towers
Senior Network Consultant
Two Trees Technology
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