An alternative to optical interconnects is to use Datacom technology to convert video to data bits and run it over Ethernet or HDBaseT cabling in a local area network (LAN). This offers several benefits: the convenience of having video streams as digitally accessible IP resources; the relative low cost of networking gear; and the improved deployment model associated with installing copper networking cables (or category cabling) in advance of the AV deployment. But there are downsides to this approach as well.
There are two types of video over IP interconnects available for HDMI. Copper network cabling and standard SFP optical modules (10Gbps over fiber). Copper is readily available and easy to install, but bandwidth declines rapidly over distance (see chart). The second type uses 10Gbps SFP optical modules, which offer more bandwidth over distance but require the installation of fiber. Even so, 10Gbps still isn’t enough bandwidth for a real 4K HDMI signal. You would need to combine two 10Gbps SFP channels to support the 18Gbps required by real 4K.
Because of bandwidth limitations, video over IP and HDBaseT solutions must compress the size of the video data stream. Compression throws away data deemed not necessary and squeezes the HDMI signal into a tighter package. The lost data is gone forever and cannot be replaced. In addition, processing is required to do the compression and can create latency issues where the video lags as the processing time interferes with the timing of the video.
Running video over IP requires building and maintaining a stable, high-speed network and having the support infrastructure necessary to maintain 100% uptime. Not every AV installation has the resources (or desire) to manage a dedicated high-speed network for video delivery.
8K is coming soon and will require 48Gbps to enjoy all its benefits. Only fiber has the inherent ability to run this much bandwidth, now and into the future. While copper-based implementations will likely need to be completely replaced, fiber-based installations can be easily modified to push 8K and beyond.