Translating then Translating again.

Unanswered Question
Sep 11th, 2008

Hi guys, I have a small issue which i fill i know the answer to but i would like to have some more opinions an best practices on this one :)

We have a centralised architecture, we have resolved an issue whereby users were dialing internally to another site but dialing the full number rather then the extension. So we put in a translation pattern to shrink the number when it was dialed to the extension and send it along the Wan. The problem we have just found out that if the Wan is down then we cannot ring that site because the number gets translated to an extension which is not able to go across the wan because the wan is down :).

Any best practices would be appreciated.. I was thinking another route pattern in the route list or AAR?

Any Help much appreciated..


I have this problem too.
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Marwan ALshawi Thu, 09/11/2008 - 02:57


u can solve this issue by makeing two dial peers

lets say ur user dial 9551234

make two dial peers

first one going though the WAN link which in this case should be a voip dial-peer and make another dial peer with the same distination pattren but gos through the pstn which ic pots dial-peer and give it a higher prefrence number and the first dial-peer will be prefered because it has the defualt preference number which is 0 if the WAN is down the call will failover to the second one which is the pstn

and apply the trnaslation profile to the voip dial-peer ony have a look at the following example

users dial 955123 u send over WAN 123 only and through the pstn if the WAN down u send 551223

creat the foolowing voice calss so that the failover between dial-peers will take only three second instead of the default 15 second

voice class h323 1

h225 timeout tcp establish 3

voice translation-rule 1

rule 1 /955\(...\)/ /\1/

voice translation-profile profile1

trnslate called 1

dial-peer voice 9 voip

destination-pattren 955...

translation-profile outgoing profile1

voice-class h323 1 (this is the calss we created above apply it to this dialpeer)

seesion target ipv4:[CCM or gateway IP]

dial-peer voice 91 pots

destination-pattren 955...

preference 2 ( this to make the VOIP matched first )

port [ur pstnport]

forward digit 5

u can forward digits as u want here we only send 55... like 55123

good luck

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hellspire69_2 Thu, 09/11/2008 - 03:11

Your a star thanks alot, this was a idea we was gonna implement before but I was trying to find a way to keep it purely on the CCM side of things... Which is why i thought of another route pattern or using AAR or so. I mean how would a mgcp sys do it? :)

Marwan ALshawi Thu, 09/11/2008 - 03:44

first this works fine with h323

with mgcp and h323 as well u could use deffrent route groups and then put them togather in on route list and assign them to on route pattren lik 955XXX

and on each route group define a port or gateway and at the route group level u can make the numprening trnasformation

by the way AAR dos not work in case of WAN link down it works only if u have gatekeer and call admition control enabled and there is no enough bandiwdth to pass the call then AAR works

and if u have two mgcp gateways u dont need two dial peers the calling system wil be handeled by CCM and u can make like:

user dial 955XXX

u ahve trnaslation pattren on ccm match pattren 955XXX and make it XXX which is internal number

with mgcp u cant do it like h323 so if WAN gos down u need to make the remote site router to operate in srst mode in this case they need to have a DID number on the remote site also ur users on the main site with CCM they need to call the whole DID number which is not transparent to them like with h323, bu the remote users with srst mode they can stil dial normal numbers but u need to trnalste them and make full dial-plan for h323 fall-back and srst mode

in my knowledge with mgcp we cam make failover based on PSTN ports not from WAN to pstn !!!

for example if u use remote site pstn and the through the WAN and the WAN down u can use ur local pstn as a failover through route groups and route list

good luck

please, if helpful Rate

hellspire69_2 Thu, 09/11/2008 - 07:30

Thanks matey really really really helpful!! :) Ive just got a real bee in my bonnet about getting it working souly on the CCM mgcp way.. but at the moment im not having much success. Im trying to use a route pattern with a called party translation the same as i had with the translation pattern but im trying to figure out how to get it to use the first trans rather then sending it out to the GW :)

Marwan ALshawi Thu, 09/11/2008 - 19:41

u can also make control through partions and CSS so u give the user a CSS that has access only to the trnaslation pattren partion and u give the translatio pattren a CSS that have access to the route pattren that should route the call after being translated

will u use CCM with MGCP? i think will not help u alot as h323 !!!

good luck

if helpful Rate and thansk for rating as well :)


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