While the term video over Internet Protocol (IP) has existed for quite some time, it essentially has been used to refer to any type of IP-based video transmission. However, regardless of the cabling medium, most of these systems to date have been supported by traditional audiovisual (AV) architectures where signals are sent and received via AV transmitters, receivers and video matrix switches rather than using true Ethernet LAN switches. This has prohibited AV transmission from truly converging onto existing network cabling infrastructures, and they have instead remained on their own standalone network. But all that is changing with AV over IP that uses standard network equipment to transmit and control AV signals.
A Step in the Right Direction
Over the past decade, balanced twisted-pair copper cabling (i.e., Category 6 and Category 6A) has become an AV-supporting medium using baluns that enable composite and analog video to operate over the twisted-pair cabling. The use of AV over twisted-pair cabling really came to fruition in 2010 with the introduction of the HDBaseT standard.
Since it was introduced by the HDBaseT Alliance, HDBaseT has evolved to support what has been dubbed “5Play”—the transmission of ultra-high definition 4K video and audio along with 100 Mb/s Ethernet (100Base-T), USB, bidirectional control signals and 100W of power (power over HDBaseT [POH]) over a single twisted-pair cable for distances up to 100 meters using standard 8P8C (RJ45) connectivity.
While HDBaseT can run over Category 5e (to limited distances) and Category 6 cabling, the HDBaseT Alliance and HDBaseT equipment vendors all recommend the use of Category 6A twisted-pair unshielded cabling at a minimum to support the bandwidth required for 4K signals and reach the full 100-meter distance. Many AV vendors recommend stepping that up to Category 6A or Category 7A shielded twisted-pair cable to ensure a truly robust performance—especially for installations with unmanaged environmental factors. Shielded Category 6A or Category 7A offers better resistance to alien crosstalk, which has a significant impact on HDBaseT signals wherever multiple cable are bundled together. Further, with POH running at a higher remote powering level of 100W, shielded cabling offers far superior heat dissipation and thermal stability.
While HDBaseT remains the most popular AV protocol over twisted-pair cabling and was a step towards using a common cabling medium, it is not true IP as it used a different packetization protocol (T-packets). Further, an HDBaseT system must use HDBaseT equipment, so it essentially must remain as a standalone system and therefore does not meet the true definition of IP convergence. Continue reading