gc

USA

IPTV Solution Architect

IPTV is a "switched video service" (not a 'download' service) which utilises internet protocols for delivery over networks operated by Telco's such as BT.

In todays video delivery, all TV channels are available at the TV and your set "tunes" to the requested channel. In a switched video service the tuner is effectively back in the network and when you request a new channel the network switches that channel onto your broadband connection.

Using todays compression technologies standard defintion video requires approx 4Mbps while High Defintion requires 16 - 20 Mbps across your broadband connection. Using the newer MPEG4 compression technologies these bandwidth requirements are approximately halved, ie 2Mbps for SD and 8 - 10 Mbps for HD.

So we can now see that 2Mbps bandwidth is the very minimum (not counting overheads and headroom on the broadband connection) will not be sufficient to provide a reasonable IPTV service, in fact most Telco operators need to consider 20 - 40 Mbps DSL connections to provide a compelling service, particulalry if they are offering the video service combined with VoIP telephony and High Speed data service concurrently. The other major impact on bandwidth utilisation is support of multiple video streams into a single household. Because IPTV is a switched service, if there are 2 TV's in the house watching different channels, that is 2 video streams over delivered over the same broadband connection.

IPTV is not a simple solution and one of the major considerations is the available bandwidth in the last mile to the home.