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Re: Tools to measure TCP connection speed

  • From: Wil Schultz
  • Date: Mon Mar 10 13:05:31 2008

A couple of tools I use from time to time are iperf and ttcp. I'll run iperf on some host and either run ttcp to it from a router or iperf to another host. You can also run ttcp router to router.


On Mar 10, 2008, at 8:51 AM, Joe Shen wrote:

we do not just want to analyze e2e performance, but to
monitor network performance at IP and TCP layer.

We monitor end-to-end ping with smokeping, but as you
know, ICMP data does not reflect application layer
permance at any time. So, we set up two hosts to
measure TCP permance.

Is there tools like smokeping to monitoring e2e TCP
connecting speed?


--- "Darden, Patrick S." <[email protected]> wrote:

Best way to do it is right after the SYN just count
"one one thousand, two one thousand" until you get
the ACK.  This works best for RFC 1149 traffic, but
is applicable for certain others as well.

I don't know of any automated tool, per se.  You
really couldn't do it *well* on the software side.
I see a few options:

1.  this invalidates itself, but it is easily
doable: get one of those ethernet cards that
includes all stack processing, and write a simple
driver that includes a timing mechanism and a
logger.  It invalidates itself because your
real-life connection speeds would depend on the
actual card you usually use, the OS, etc. ad
nauseum, and you would be bypassing all of those.

2.  if you are using a "free" as in open source OS,
specifically as in Linux or FreeBSD, then you could
write a simple kernel module that could do it.  It
would still be wrong--but depending on your skill it
wouldn't be too wrong.

3.  this might actually work for you.  Check to see
how many total TCP connections your OS can handle,
make sure your TCP timeout is set to the default 15
minutes, then set up a simple perl script that
simply starts a timer, opens sockets as fast as it
can, and when it reaches the total the OS can handle
it lets you know the time passed.  Take that and
divide by total number of connections and you get
the average....  It won't be very accurate, but it
will give you some kind of idea.

Please forgive the humor....

--Patrick Darden

-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of
Joe Shen
Sent: Monday, March 10, 2008 5:00 AM
Subject: Tools to measure TCP connection speed


 is there any tool could measue e2e TCP connection

e.g. we want to measue the delay between the TCP SYN and receiving SYN ACK packet.


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