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Video streaming In India
• Streaming media is media that is consumed (read, heard, viewed) while it is being delivered. Streaming is more a property of the delivery system than the media itself. The distinction is usually applied to media that are distributed over computer networks; most other delivery systems are either inherently streaming (radio, television) or inherently non-streaming (books, video cassettes, audio CDs).
• The word 'stream' is also used as a verb, meaning to deliver streaming media. The difference between Video Conferencing and Video streaming in simple terms is that Video conferencing is a two way and multiway collaboration of audio, video and data, whereas streaming is a one way delivery of audio, video and data. Ofcourse the return path can be a data chat mode in a streaming application.
• The big challenge in Video conferencing application is the high bandwidth requirement at the central Multi Conference Server which will be twice the number of users connected multiplied by the bandwidth at which the conference is taking place and hence the reachability is limited based on the available bandwidth on the unicast mode. In Streaming, over a multicast network, only the bandwidth at which the stream is captured is used irrespective of the number of users who receive the stream. Over the unicast mode, the bandwidth required would be equal to the number of users multiplied by the bandwidth at which the stream is being captured.
• Protocol Issue • Designing a network protocol to support streaming media
raises many issues. Datagram protocols, such as the User Datagram Protocol (UDP), send the media stream as a series of small packets. This is simple and efficient; however, packets are liable to be lost or corrupted in transit. Depending on the protocol and the extent of the loss, the client may be able to recover the data with error correction techniques, may interpolate over the missing data, or may suffer a dropout.
• The Real Time Streaming Protocol (RTSP), Real-time Transport Protocol (RTP) and the Real-time Transport Control Protocol (RTCP) were specifically designed to stream media over networks. The latter two are built on top of UDP.
• Reliable protocols, such as the Transmission Control Protocol (TCP), guarantee correct delivery of each bit in the media stream. However, they accomplish this with a system of timeouts and retries, which makes them more complex to implement. It also means that when there is data loss on the network, the media stream stalls while the protocol handlers detect the loss and retransmit the missing data. Clients can minimize the effect of this by buffering data for display.
Hence when designing a streaming application, knowledge of Networks design, Quality of video streaming service over IP network, and the multimedia capturing tools – audio, video, data – are essential to deliver a smooth media stream.
