In standards-based IPTV systems, the primary underlying protocols used are:
- Live IPTV uses IGMP version 2 or IGMP version 3 for IPv4 for connecting to a multicast stream (TV channel) and for changing from one multicast stream to another (TV channel change). IGMP operates within LAN's or VLAN's so other protocols, such as Protocol Independent Multicast (PIM), are used to route IPTV multicast streams from one LAN segment to another.
- VOD uses UDP or RTP protocols for channel streams and control is done using the control protocol RTSP (Real Time Streaming Protocol).
- NPVR (network personal video recorder), like VOD, uses UDP or RTP for IPTV streams, and the RTSP control protocol for end-user control communications.