I discovered some Joomla extension for web seminar.

For any website coded in PHP, wordpress or joomla , what each one is the prerequisite to include a Web seminar feature ?

Expensive / Flex is needed!!

The way i recieve the live feeds to this site. Could it be same like live broadcasting of the cricket match? How it's done?

Produce some hints to look and discover

Subscribe to http://www.ustream.tv/ and embed it inside your site.