Page 1 of 1

IP-phones at remote site

Posted: 15 Feb 2009 06:57
by immadov
Dears

I need the experts advice.

I am going to install 32 IP-phones in a remote site without installing any Media Gateways there. we have 2 Mb/s WAN link and Qos is well configured to give prority to the voice traffic. call admission controll will be configured to allow only 6 simultinous calls over the WAN link with G729a commpression for extra domain calls.

our provider advises me to install MG for remote sites that include more than 10 IP-phones but i didn't find any reason prevent me from installing extra devices without installing M-Gateway.
I am wondering here if there is any document or recomendation from alcatel about the number of IP-phones that can be installed at remote sites without installing MG.

In my case i need all external calls to go in/out through the central site and i can't imagin what extra benefites that i will get from installing MG other than the signaling backup.

note: i have 3 remote sites, each of them enclose 14 IP-phones. no MG and untill now i didn't face any problem.

Re: IP-phones at remote site

Posted: 15 Feb 2009 08:42
by krzysioD
Maybe it's a economic suggestion: buy more MG :>

but for situation that you describe (no Telco external lines in branch offices) then well, that will give you
MG+T0:
Backup link to main MG (note one MG can rescue one MG, so if 2 WAN points go down... )
Monthly rate for T0.
MG + PCS:
local communication by ip-phones, possibility to survive big crash of WAN.
MG + PCS + T0/APA:
local + remote communication by ip-phones, surviving crash of WAN and/or CPUs at main site (or 2 sites if spartial redundancy)
monthly rate, but you could go with one APA :)

Note: often provider of your WAN is very same (as cable/fibre goes) provider of your PSTN/APAor ISDN/T0 line... so you backup for router failure not the big J.C.B. (aka Jacob) doing some ground-work.

What i would do is to say, have in big branch offices a GSM gateway (2-4 SIM card / 1-2 T0) + PCS + GD (MADA8) and a router with GSM inertnet gateway as backup for your DATA. Then negotiate with GSM provider :>

As for 10-15 IP-phones, how much does it cost for your company to reach key persons in each office by GSM? Maybe everyone in your company have a GSM with smalles monthly rate that could be used to reach them if they are needed?
Or this is key for your company to have this 10-15 people "in touch", i think this is correct question.

Re: IP-phones at remote site

Posted: 02 May 2009 19:30
by frank
We have over 300 remote workers, each of them in a different state, different town.. Nobody use a remote gateway.. They all work good, as long as the bandwidth can support the traffic.

The only time they don't have phones is when their internet goes down :)

For the branch offices, we use PCS