H.264 HDMI extenders can transmit HD video and audio over one cat5e/cat6 cable, over TCP/IP standard, support one to many applications over Ethernet, or even Wireless LAN network.
HDMI over wireless extender
HDMI over Ethernet LAN extender, Point-to-Point & Multipoint Support
HDMI over Ethernet LAN 4 port Point to Multipoint Transmission System Set
H.264 HDMI Extender over TCP/IP