with regards to whether GKRCS is used or direct signalling it could be either. I’ve never configured
the OpenGK before but other gatekeepers will often have the ability to be configured for either. If required a gatekeeper manufacturer could program their gatekeeper to be configured to allow GKRCS for some type of call and direct signalling for others.
This could be decided based upon a number of criteria such as called number, calling number, etc.
If you have a LAN sniffer capable of decoding H.323 then you will be able to see if the gatekeeper is
doing GKRCS or direct.
With regards to the Avirt GK which you are using and routed call support for the OpenGK I’d take a
guess that both are refering/using
the LRQ (location request) method.
Lets say that you have an H.323 PABX which handles all numbers in the 2xxx range. The next site has an H.323 PABX which handles numbers in the 3xxx range. If a user on the 2xxx PABX dials 3333 then its own H.323 PABX will send an LRQ message to the 3xxx H.323 PABX requesting the IP address of user with alias 3333. Hopefully the
3xxx H.323 PABX will then return the IP address of 3333 to the user on 2xxx wishing to call 3333. The IP address should be returned in a
LCF (location confirm message).
Each H.323 PABX/gatekeeper needs to be configured with the IP address of every other GK covering
a number range that it may want to reach.
The same principal applies to GK’s on the internet or which are on a LAN and can be configured to reach GK’s on the internet.
Some gatekeeper manufacturers use other methods such as having their
gatekeepers which all cover different zones talk to a central database using either a proprietary method or something like LDAP. However if these gatekeepers want to communicate to other GK’s from different manufacturers they will have to use the LRQ method.
I’m not aware of any other Opensource GK’s for WIN32.