From: ROBERT LEUGERS (RLeugers@familydollar.com)
Date: Fri Aug 17 2007 - 15:18:28 ART
Because the TCP stack on your machine has throughput limitations based
on a single thread? Your disk write speed is bad? Full buffers (tcp
frozen windows) or packet drops (requiring retransmit requests, data
retransmission, acknowledgements, and back-off with slow start from a
fraction of the previous rate) on the destination might do it also?
Because your testing methodology/program can't push the rate based on
the way the application under test behaves (use a UDP or TCP-based test
instead of ICMP)?
These are just a few possibilities. Very hard to tell. BTW -- this
doesn't eliminate the possibility the switch is another source of the
problem.
I can tell you from experience that some applications misbehave over
very good networks because of the way they actually operate over the
network. Database queries, for example, don't always behave very well
over high-delay WANs if they are searching through a huge table
line-by-line until they get the answer(s). The same database works
blindingly fast if the query is executed locally on the database.
Another thing is that Ping does not really do a throughput test. It
tests request/response and rough two-way delay based on ICMP echo and
echo-reply, but not necessarily throughput as no data is really being
transmitted.
Multiple concurrent ftp's from different windows might push the rate up.
A traffic generator might do it also. There are free ones about.
Use one of these methods and the throughput might get better.
Rob Leugers
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Sean.Zimmerman@clubcorp.com
Sent: Friday, August 17, 2007 10:49 AM
To: sirus MOGHADASIAN
Cc: Cisco certification; nobody@groupstudy.com
Subject: Re: simple question: why I get throughput of maximum 1Mbps in
network that consists of 2 hosts and 1 switch!!?
If I had to guess, I'd say duplex mismatch. Is it a 10/100 or
10/100/1000
switch? How about the NICs?
Sean #18225
"sirus MOGHADASIAN" <cyrus.mgh@gmail.com>
Sent by: nobody@groupstudy.com
08/16/2007 08:43 PM
Please respond to
"sirus MOGHADASIAN" <cyrus.mgh@gmail.com>
To
"Cisco certification" <ccielab@groupstudy.com>
cc
Subject
simple question: why I get throughput of maximum 1Mbps in network that
consists of 2 hosts and 1 switch!!?
Hi group,
simple question: why I get throughput of maximum 1Mbps in network that
consist of 2 host and 1 switch!!?
My OS is windows , even more interesting if I use access pint for one of
two
hosts with 802.11g I reach only 120KBps .
What this issue stem from?
Sirus
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