[Help] IP Telphony bandwidth estimations & Asterisk/CRM

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 ?

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?

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?

Have a look here on bandwidth:


And here on codecs that cost vs ‘free’:


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.

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


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

ahh, forgot that one :smile: