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New Member

H323 trunk vs Qsig trunk

Iam a bit confused between the 2. We have a h323 trunk between an Avaya system and Cisco and are able to call successfully

When we should be using a Qsig trunk and when H323 between the 2 systems. What are the Pros and Cons of each


Hall of Fame Super Silver

Re: H323 trunk vs Qsig trunk

H.323 Trunk is an IP (virtual) connection between 2 devices.

QSIG is an ISDN protocol that allows for TDM integration between 2 systems, this requires a physical connection (cable, cards) between the 2.

QSIG was the best solution for PBX integrations in the TDM days where IP protocols were not available.

These days new PBXes support IP protocols and H323 or SIP trunks are the best options.

If your systems support H323 (which obviously it does) then there is no reason to go to QSIG.

HTH, please rate all posts!


New Member

Re: H323 trunk vs Qsig trunk

thanks for the explanation


New Member

Re: H323 trunk vs Qsig trunk

Hi Friend,

We want to have similar integration between Alcatel PBX & Cisco 2811 over H.323

Can u plz share what are the parameters to be configured on both the sides!!! I am in deep trouble so asked help from you....

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