). Encoding allows the variance of the amount of information transmitted wit the final result being a variable quality of video as well at the receiving or decoding end (Shenoda). The intent of this setup is to allow the utilization of different but constant transmission rates (Shenoda). This allows the user to choose the transmission rate which is most economical in terms of maximizing video quality and of minimizing transport cost (Shenoda). Guidelines as to what is typical in this type of setup is that quality first becomes acceptable starting with 384 kbits/s and improves substantially at 1 Mbit/s and above (Shenoda). There are numerous other recommendations for multiplexing, voice compression, the utilization of dual cameras in teleconferencing applications, etc. (Shenoda). MPEG differs form the above standards in that the protocol stack incorporates a “core physical layer, a network and transport adaptation overlay and several elements above network transport (Shenoda).” Other considerations include program streaming (multimedia multiplexing) which incorporated digitized audio utilizing ISO/IEC 13818-3 voice coding (Shenoda). Multimedia multiplexing also incorporates digitized video utilizing H.262 video codec and signals for user to user control (Shenoda). MPEG is broken into MPEG-1 and MPEG-2 with the latter having the highest resolution and a richer syntax (Shenoda). MPEG-1, however, allows even lower transmission rates because of its ability to encode at even lower resolution (Shenoda). This is particularly useful for applications such as CD-ROMs (Shenoda). Numerous ITU and International Standards Organization are associated with MPEG (Shenoda). On-line ApplicationMany of the standards which address clocking, synchronization, delay, packetization, adaptation layers and connection management and routing are currently in place and are in a constant state of evolution, others are being established (Sheno...
