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IP trunks 1

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oldtimers

Vendor
Jan 16, 2007
47
GB
What is the maximum number of sip trunks you can have into an IP office??
Thanks in advance for your help
James
 
128 the same as vcm channels



RTFM.gif



ACS - Implement IP Office
ACA - Implement IP Telephony -- ACA - Design IP Telephony
ACA - Voice Services Management
______________
Women and cats can do as they please and men and dogs should relax and get used to the idea!
 
128 Concurrent calls over some theoretical number less than a million programmed trunks. That is assuming you are using g.711, which you probably are not.

120 at g.729
88 at g.723

 
If you use PRI interfaces then the max ISDN trunks is 240, so at the very least the system should be capable of 240 SIP trunks.
128 max SIP trunks doesn't make sense.

Also why would you need 128 VCM channels to run 128 IP trunks.
The way it works is that for IP to IP a VCM channel is only needed to establish the call. It is not required during the call itself.
Is there any activity from the IP Office during the call? My understanding is that there is not!

It seems to me that the maximum number is determined by the troughput of the network speed. ie if the SIP trunk was over a 10M circuit then the max could be over 800 based on 12K per channel.

Has anybody out there actualy tested this? The answer 128 SIP trunks does not seem right. Does anybody know the truth here?
 
Lets not forget SIP licences, and VCM Licences ( IP500 ).
You cant make 64 simultanious calls if You're only licenced for 25! Some sites grew over the Years, never adding licences!
VCM could be an issue, IP Phones usually release the VCM once conected, TDM Phones do NOT!
Of coures My favorite still is when none of the phones work because VOIP bill wasn't paid, I still come accross this, lol.

Andre
 
I guess we assumed TDM phones as you didnt specify.
Ill have to give you a star on your own post oldtimers, as long as your IP phones are using the same codec your trunks are using they shouldnt take a VCM after the connection. Same goes if you are trying to do some kind of ip-ip trunk routing.

i guess my point is that i have no idea and havent seen an answer in any docs.

 
There isn't any doc mentioning it as far as i know
If you only use ip phones and the codec is the same for all then you probably can go higher untill the system reaches it's limit

VCM usage is done the next way:


SIP Calls

• SIP Line Call to/from Non-IP Devices
Voice compression channel required.
• Outgoing SIP Line Call from IP Device
No voice compression channel required.
• Incoming SIP Line Call to IP Device
Voice compression channel reserved until call connected.

RTFM.gif



ACS - Implement IP Office
ACA - Implement IP Telephony -- ACA - Design IP Telephony
ACA - Voice Services Management
______________
Women and cats can do as they please and men and dogs should relax and get used to the idea!
 
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