IPTV networks

An IPTV network essentially consists of three fundamental components: a content aggregation segment, a content distribution segment and a consumption device.

Aggregation takes place at a super headend where programming is collected from multiple sources: off air, fiber networks and satellite feeds. This content is encoded and multiplexed into an MPEG transport stream, IP encapsulated, L-band modulated and then uplinked to a satellite.

AVC or VC-1 codecs maximize transponder bandwidth efficiency. This can also eliminate transcoding farther downstream. AVC/VC-1 compressed video is IP encapsulated and multiplexed in an MPEG transport stream. Using this methodology, content can be delivered to the customer's premise and decoded by the STB or PC.

IPTV system operators build regional headends where additional content is received. This content can arrive from a satellite, off air or over landlines. In the IPTV network operations center, EPG information is generated, content is encrypted and conditional access and DRM control is implemented by middleware. Customer service and billing systems are integrated into the content management system layer.

Delivery to the customer continues over telco or cable broadband systems to a local DSLAM (Digital Subscriber Line-Access Multiplexer), and then the last mile to an IPTV STB or media PC that completes the system. The MPEG-IP packets are transported as UDP (User Datagram Protocol) packets using RTSP (Real-Time Streaming Protocol.)