I've been pretty vocal about my disdain for HDMI and my preference for DisplayPort on my PC. I might not like HDMI as a protocol, but the hardware used for it is pretty high quality, which makes it useful for other things. One of which I can't decide if it's cursed or genius, but probably somewhere in between.

In the early 2010s, makers of managed network switches had a problem. The driving force of enterprise connectivity required greater-than-Gigabit speeds, or switches with more ports for office and datacenter use, which made things tricky because the interconnects between switches were mostly Gigabit, using either SFP or standard twisted-pair cabling. But you know what is capable of more than Gigabit bandwidth? Yep, HDMI, and that's what some networking appliance makers decided to do.

Some companies have taken liberties with HDMI

Netgear and Dell have a lot to answer for

Flicking through the images above, you might start wondering what I'm talking about, because they look like normal 48-port Gigabit managed network switches at first glance. At least, until you get to the last image and see something you might notice is out of place.

Yes, there are two HDMI ports on the back of the switches, as up and down links to chain up to six of these together in a stack. They're not connected to display chips like anything else with HDMI installed; instead, they use the high-quality copper wiring as a stand-in for 10GbE networking cables. These work at Layer 1 and are simply there to provide a multi-Gig connection between the switches.

Used like this, the HDMI cables are full-duplex, and the recommendation from Netgear is to stack them in a ring, so I'd use two HDMI cables with my two switches, for redundancy, but would do the same with a cable from the top to bottom of the stack if I was using more. Stacking lets you manage the entire stack from a unified GUI on one IP address, which is great.

But it had one important advantage

At the time, most network switches were Gigabit everywhere. The SFP ports on the front of this model are capped at Gigabit, and so are the Ethernet ports. But High Speed HDMI is 10.2 Gbps, Premium High Speed is 18 Gbps, and Ultra High Speed is 48 Gbps. Now, I'm pretty sure the ports here are HDMI 1.4, which aligns with the new High Speed HDMI moniker, so we get roughly 10 Gbps connection speed once overhead is taken into account.

That's plenty of bandwidth for stacking up to six of these 48-port switches, making this a pretty smart engineering decision (even if I hate it). I've even seen newer, more expensive versions of this with 40 GbE stacking connections and Ultra High Speed HDMI cables. Around that time, fiber optics became relatively affordable, so networking switched to it for faster connections, but for about a decade, HDMI remained a regular fixture in the network stack of many companies.

The connector might be cursed, but these are pretty good switches

Plenty of enterprise features for not much cash (since eBay is the only place to get them)

At the time, these were fantastic network switches, and they're still pretty good a decade later. I get 96 Gbps backplane bandwidth, can stack up to six of them for a single management page, and can set 8,000 MAC addresses per system for QoS and port-based rules.

• 48 Gigabit ports
• Four SFP Gigabit fiber ports
• VLANs (including dedicated management VLAN)
• Port-based QoS
• Link aggregation (LACP)
• Storm control
• Port mirroring to go to IDS/IDP or other uses
• Cable testing

Plus, there's probably a good few years of life left in them. The mean time between failures for this switch is roughly 14 years, and there's no way they were in operation that long before they were pulled and put on eBay.

96 Gigabit ports at my disposal

I have no idea what I'm going to use 96 ports for in my home lab, but I look forward to figuring it out. If nothing else, it's a fun piece of networking history for my collection, where HDMI was used for something other than video transmission. They'll come in handy if I get enough SBCs to make a giant Kubernetes cluster, that's for sure.

I still don't want HDMI on my computer, but my network rack is fine

I'm not entirely sure if I want HDMI in my network rack now that 10 GbE over twisted-pair cable is widespread, but I had to pick up a couple of these cursed objects to play with in the home lab. They were cheap, too. To say they were hundreds or maybe even thousands new, the two cost me under $80.