From 0f34455fc02d31402f6f28e0019972f970f45940 Mon Sep 17 00:00:00 2001 From: Stephane Bortzmeyer Date: Sun, 25 Jun 2000 13:50:27 +0000 Subject: [PATCH] New details file and link to it. --- Web/details.wml | 96 +++++++++++++++++++++++++++++++++++++++++++++++++ Web/index.wml | 5 +-- 2 files changed, 99 insertions(+), 2 deletions(-) create mode 100644 Web/details.wml diff --git a/Web/details.wml b/Web/details.wml new file mode 100644 index 0000000..b6980f6 --- /dev/null +++ b/Web/details.wml @@ -0,0 +1,96 @@ +#use wml::template Title="echoping details" + + + + +

echo service

+ +

echoping assumes the remote host accepts such connections. Experience show that +most Internet routers do and many hosts also. However, some Unices are not +shipped with this service enabled and, anyway, the administrator is always +free to close it (I think they shouldn't). echoping has therefore less chance +to succeed than ping or bing. (On a typical Unix box, "echo" service is +configured in /etc/inetd.conf but see the CERT advisory.) + +

What does it measure?

+ +

echoping simply shows the elapsed time, including the time to set up the TCP +connection and to transfer the data (but excluding the time for the +- possible - DNS call). Therefore, it is unsuitable to physical +line raw throughput measures (unlike bing). On the other end, the action it +performs are close from a HTTP request and it is meaningful to use it +(carefully) to measure Web performances. + +

UDP and inetd

+ +

With UDP servers you can have surprises: the first test is quite often +much slower since inetd has to launch the process. After that, the process +stays a while so the next texts run faster. + +

A nice example

+ +

There are many, many traps when measuring something on the Internet. Just one +example: 'echoping -w 0 -n 4 a-sunOS-machine' and you'll see the first test +succeed in a very short time (if you are close from the machine) and all of +the others take a much longer time (one second). With '-w 1' (wait one second +between tests, the default), everything works fine: it seems the sockets on +SunOS need time to recover :-) + +

To measure performances on the Internet you can also see

+ +

Unix

+ + + +

MacOS

+ + + +

MS-Windows

+ +(I have little knowledge of that environment and I tested nothing.) + + + +

Windows-NT

+ +echo and other services can (apparently) be provided within +'Simple TCP/IP Services' which +can be enabled through the Network Control Panel + +

Web clients

+ +You can ping or traceroute on the Web. See + or + . + + +

Use all of them with care, the result is not obvious to interpret. + +

And don't forget to read RFC 1470 ("Tools for Monitoring and Debugging +TCP/IP Internets and Interconnected Devices"), specially its "Benchmark" +section and the Richard Stevens' books (all of them), published by +Addison-Wesley. diff --git a/Web/index.wml b/Web/index.wml index d535f4c..c825e0e 100644 --- a/Web/index.wml +++ b/Web/index.wml @@ -10,7 +10,8 @@ hurry :-) Download, if you wish. (Or you may prefer access the latest developments via CVS: the -module is named "SRC".) +module is named "SRC".) You may be interested in SourceForge's page +about echoping, with the bug reports, etc.

To use it, simply: @@ -20,7 +21,7 @@ module is named "SRC".)

or use the options before the machine name (see the man page). -

See the DETAILS file for various traps when benchmarking networks, +

See the DETAILS file for various traps when benchmarking networks, specially with this program.

In any case, be polite: don't bother the remote host with many repeated