[Help] IP Telphony bandwidth estimations & Asterisk/CRM


#1

If I replace all digital Telephones with IP telephones , how big the Bandwidth should I have in the office
can anybody recommand me some literature about how to conect Asteris with CRM ?


#2

are you talking internal or external bandwidth?

How much BW you need depends on how many active calls you have and what codec you’re using. A compressed codec like iLBC or G.729 will fit several calls into the same bandwidth of one uncompressed (G.711 ulaw/alaw) call.

How many users do you have, and how many concurrant outgoing lines will you need?


#3

We have about 20 telephones,and we estimate that 10 concurrent outgoing calls will often occur.
All the codec you mentioned are free ?,or I must pay for that.
How much BW should I have ,if I take the normal codec like g.711 ulaw/alaw.
About the codec I know nothing about it , can you recommend some literature?
thanks


#4

Have a look here on bandwidth:

voip-info.org/wiki-Bandwidth+consumption

And here on codecs that cost vs ‘free’:

voip-info.org/wiki-Codecs


#5

the only codec that is NOT free is G.729.

On your internal network, bandwidth won’t be a concern (100mbit lan has plenty for 20 calls). External might be an issue.

Check out the wiki-codecs link. The best quality (g.711 ulaw/alaw) takes up 64kbit/sec plus overhead. If you want to use compression to save external bandwidth, it’s preferable to use a codec like GSM or iLBC. Alternatively, you can use G.729 if your providers don’t support GSM or iLBC.


#6

Actually, G723 has a cost associated with it if not used in passthrough mode.


#7

wow,thanks


#8

Actually, G723 has a cost associated with it if not used in passthrough mode.[/quote]

ahh, forgot that one :smile: