Flash can use the RTMP protocol to exchange data between a server and a client.
How do you typically access this functionality in AS2 or AS3/Flex? For example to use sockets you use the XMLSocket (AS2) or Socket (AS3) classes.
Does the server-side RTMP software use Sockets under the covers? or is it HTTP with tunneling?
The Real-Time Messaging Protocol (RTMP) was designed for high-performance transmission of audio, video, and data between Adobe Flash and a server. RTMP is now available as an open specification to create products and technology that enable delivery of video, audio, and data in the open AMF, SWF, FLV, and F4V formats compatible with Adobe Flash Player.