[asterisk-users] Article - a method on how to evaluate an Asterisk server

[Ioan Indreias]

Hello all,

I would like to share with you an article [1] we have issued last week
(sorry, currently only in Romanian language - we plan to provide an
English version soon).

This article is describing a method to be used for obtaining the
maximum number of SIP simultaneous calls an Asterisk server could
process safely (meaning no errors/maintain control of the machine and
without RTP frame drops)

We used SIPP (with modified uas and uac_pcap scenarios) + 2 scripts
for controlling the test (one is running on the tested Asterisk server
- start-test.sh, for data collection and load analysis and the other
is running on the SIPP+Asterisk testing machine, for call quality
control and SIPP instance control - sipp-controller.sh) + customized
Asterisk dialplans and SIP configuration.

The best part is that this method could be used for testing any type
of Asterisk PBXs (from embedded to bigger servers), having
capabilities to balance the load to several SIPP call
generators/answer engines in case the tested server have more
processing power than the testing machine. We have use this method to
test 4 machines and the results are for the maximum number of G.711
ulaw - ulaw SIP calls are summarized in [2].

Also, this method is describing how to configure SIPP and Asterisk in
order to test different transcoding scenarios (like ulaw to gsm).

Basically the controller script increase the number of simultaneous
calls (one SIPP call generator is calling an extension on the tested
Asterisk server and the call is answered by anotther SIPP answer
engine) till one of the load or quality tests failed.

The tests are:
	- load evaluation -> how much time a `sleep 1` command take on the
tested server
	- SIP RTT evaluation -> what is the average RTT of a SIP INVITE message
	- audio quality evaluation -> based on evaluating of the call
"monitor" file size  (on the tested Asterisk server we use an echo
application and the file is recorded on the testing machine)

Even that the translation service provided free by Google is not the
best way to read our article in English (or other languages) I
encourage you to read it (the pictures and the results are very easy
to understand) and send your feedback or comments here.

Best regards,
--
Ioan Indreias
www.modulo.ro

Notes:
[1] - http://www.modulo.ro/Modulo/ro/Articole/Determinarea_capacitatii_maxime_a_unei_centrale_Asterisk.html

[2] Maximum number of G.711 ulaw - ulaw SIP calls
	 38 - Norhtec MicroClient Jr DX
	130 - VIA EPIA EN12000EG
	176 - Asus Pundit R350
	320 - Gigabyte 945GCM-S2L