[Asterisk-Users] Enhancing performance and utility of an Asterisk machine

[Erick Perez]

Hi, some questions/comments about performance/utility of * and * hardware

I've been reading this list for a few weeks and I think I have
compiled the better feelings of the users.
please correct me if I'm wrong, still learning * ....
Will be nice to see something like this in a wiki.
After being flamed and corrected I will repost "clean" data.

1- Transcoding is the process of converting from one codec to another.
Example from G.723.1 to G.729.
2- It does not matter if you're doing voicemail or a call. If one of
the ends does not "speak" the same codec, transcoding is involved.
3- Transcoding is very CPU intensive and should be avoided when possible.
4- DSP based cards will improve * performance by offloading work from the CPU.
5- If you configure the SIP phones to use the same codec (G.729) .
then no transcoding is involved when they talk to each other.
6- If you're doing VoIP to POTS/T1/E1 you're doing transcoding.
6a-If youre using G.711 as the codec and doing VoIP to POTS/T1/E1
you're NOT doing transcoding?
6b- More than 50 calls VoIP to POTS/T1/E1 will kill an * box due to
excesive transcoding??????
6bb- unless using quad machines, plenty of RAM and DSP cards?????

File Codecs
What codec should I use to save my voicemail and IVR prompts?

Hardware
DTMF generation and cut-through detection are features you must get on a card
Integrated DSP Echo Cancellation is a must.
any other features that I should go out and buy? * compatible hardware
of course.

Another off-this-topic question
i read that the TDM cards from Digium are having some problems. Im
just saying what i read. I have no intention to discuss the problems.
But if this is true, then * VoIP players like Nufone with their 80+ *
server farms.....are using what E1/T1/DS3/etc * compatible hardware?
are Digium and VoiceTronix the only * compatible hardware? I googled a
lot and found "will work with opensource apps" but do not explicitly
say Asterisk.
(Shido can you shed some light on this?)

Since I am an end user/Unix sysadmin/VoIP learner I think I will ask
the forum to give me the task of doing a wiki or update existing wikis
and voip-info.org (when we all agree of course).

I bought the * book from signate. It's very good but lack some
things...I'm waiting for the next revision (if any).
-- 

-------------------------------------------
Erick Perez
Linux User 376588
http://counter.li.org/  (Get counted!!!)