Sunday, 20 March 2011


IPTV is sensitive to packet loss and delays if the streamed data is unreliable. IPTV has strict minimum speed requirements in order to facilitate the right number of frames per second to deliver moving pictures. This means that the limited connection speed/bandwidth available for a large IPTV customer base can reduce the service quality delivered.

Although a few countries have very high speed broadband-enabled populations, such as South Korea with 6 million homes benefiting from a minimum connection speed of 100Mbit/s, in other countries (such as the UK) legacy networks struggle to provide 3-5 Mbit/s[61] and so simultaneous provision to the home of TV channels, VOIP and Internet access may not be viable. The last mile delivery for IPTV usually has a bandwidth restriction that only allows a small number of simultaneous TV channel streams – typically from one to three – to be delivered.[62]

Streaming IPTV across wireless links within the home has proved troublesome; not due to bandwidth limitations as many assume, but due to issues with multipath and reflections of the RF signal carrying the IP data packets. An IPTV stream is sensitive to packets arriving at the right time and in the right order. Improvements in wireless technology are now starting to provide equipment to solve the problem.[63]

Due to the limitations of wireless, most IPTV service providers today use wired home networking technologies instead of wireless technologies like 802.11. Service Providers such as AT&T (which makes extensive use of wireline home networking as part of its U-Verse IPTV service) have expressed support for the work done in this direction by ITU-T, which has adopted Recommendation (also known as G.9960), which is a next generation home networking standard that specifies a common PHY/MAC that can operate over any home wiring (power lines, phone lines or coaxial cables)

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