Originally Posted by marcosdasilva

Hello Chitra. all of what's been said in prior replies is true and has tought us all on the "online booking" and "offline booking". So, we should be thankful to those who shared their expertise.
Here is my suggestion to you, though. Check out "YTB Travel Network". They offer a booking system where you may utilize your Company name and take advantage of a online booking system that compares to "flight search engine" mechanisms.
There is a small investment involved.
They also offer good customer services for the "RTAs" (Referring Travel Agents) who subscribe to their product and work under their rules and regulations.
Their site offers a International Flights booking thread that might just serve your purpose.
I use the system and it works out great for my Company.
www.worldtravelplanners.com

Good luck, friend.

Marcos.