Here is the scenario:
5 sites located in AU, US, UK, DE. Three sites have CME and two sites have CM.(6.1(1)
Each site has his own IOS gateway with connectivity to PSTN.
I can either create trunks between callmanagers (GK controlled) OR just send calls through gateways (GTWYs are connected to GK)
What advantage do I gain by creating GK controlled trunks between callmanagers Vs. just sending the calls trhough H.323 gateways?