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New Member

Voice Trunk PBX-IP-PBX

Trying to replace the 2 t-1 tie lines inbetween pbx's. With a 3845 and a 2811 router useing 1 VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 in each end.

Basically got

controller T1 0/2/0

framing esf

linecode b8zs

ds0-group 0 timeslots 1 type e&m-wink-start

ds0-group 1 timeslots 2 type e&m-wink-start

voice-port 0/2/0:0

timeouts call-disconnect 3

connection trunk 201 answer-mode

dial-peer voice 1 pots

destination-pattern 100

port 0/2/0:0

This is x48 timeslots/dial-peer's ect on both ends

I am hitting the loopback on each router with this:

dial-peer voice 50 voip

destination-pattern 2..

session target ipv4:

dtmf-relay h245-signal h245-alphanumeric

ip qos dscp cs5 media

Basically the trunk comes up but the avaya pbx on each end doesnt show anything. am I missing something?

Hall of Fame Super Gold

Re: Voice Trunk PBX-IP-PBX


Instead of connection trunk, you could let the router interpret the numbers from the pbx instead. You will need 48 DP pots because you are have created on voice-port per channel. You can reduce reduce this to 2 if you put 24 timeslots in the ds0-group, you would loose 1:1 mapping between PBX's timeslots, but probably doesn't matter.

New Member

Re: Voice Trunk PBX-IP-PBX

Actually I tried 1 ds0-group for each line. It didn't work as not all the lines would come up. With this config i get all the channels to come up and trunk.

Hall of Fame Super Gold

Re: Voice Trunk PBX-IP-PBX

So it's working now ?


Re: Voice Trunk PBX-IP-PBX

Hi Paolo,

we need to connect two old PBX through IP (PBX_A-2821--IP--2821-PBX_B)

by reading cisco docs, actually, i would choose "connection trunk". can you please describe your proposal? what are the advantages and/or the requirements?

Hall of Fame Super Gold

Re: Voice Trunk PBX-IP-PBX

Hi, as mentioned above you can use connection trunk, but a regular configuration where you received the numbers gives you more control and debug. So I suggest you configure the signalling used by the PBX and interpret the number, that interface is that ?

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