Then you just install a lightning arrestor on your comms circuit - I have a mast way up the hill to provide our connectivity here, and use one on the Ethernet line down to prevent issues (like a house fire) from a strike.
There's really no "just" concerning lightning protection. You can just add some protection, to code or above, but it may not work. Nature can be unforgiving.
You have to assume a direct hit by lightening will fry your hardware, period, full stop - proper grounding and lightning protection however will mean that the hardware does not catch fire.
There are lightning protectors that will absorb a direct lightning strike. Most antennas on hilltops and tall buildings have them. They take lightning strikes routinely.
Here's some ARRL material on lightning protection.[1]
It's not difficult, but it's not miniature. A classic design was a soup-can sized device with a coax connector on each end and a hulking big ground connection on the can. Inside was a spark gap with dime-sized silver contacts, and a few turns of copper busbar as an inductor to smooth out the spike that got past the spark gap. That goes where the cable enters the building. Similar units today tend to be smaller. There will still be serious metal boxes.[1]
You need a serious ground. As in hulking big copper cable to a long ground rod. Grounding to a pipe is no longer allowed; there might be plastic pipe somewhere in the system, either now or in the future.
The next stage is a "central office protector". This is a gas tube with three terminals - both sides of the line, and ground. So it's an enclosed spark gap in an inert gas. An overvoltage will ionize the gas and short it to ground. Telco central offices have one of those on each line. They're plug-in devices that sometimes have to be replaced.
There's a lot of obviously fake stuff on eBay and Amazon in this area. 2D logos superimposed on curved surfaces, even. There's a standard, UL 497B. If it doesn't have that certification, don't buy.
I'm a licensed radio amateur since 1996, I've spent about 20 years working in the cellular/telecom/two way radio industry, and I've done Motorola R56 inspections (as well as other proprietary grounding standards).
I respectfully disagree, a direct lightning strike almost certainly will take out gear at a cell site, even when properly grounded. Similarly a direct strike to telco cable will certainly fuse the 16-20ga wire in the cable itself at the first point its near a ground. Carbons, Glass Tubes, and other similar hardware will protect you in the event of a nearby strike (like to a lightning rod on a tower, or building) - but wont save you if the infrastructure is struck itself.
Generally the point of lightning protection systems is to well ground the tower, to draw the lightening away - so the tower and grounding system can protect the equipment - that isn't a direct strike by what I'm saying here - a direct strike would be if it struck the antenna itself.
Thats the perspective I have from cleaning up from strikes at well grounded and protected tower sites.
Yes, few antennas really need to remain operational against direct hits. Nor do they usually need to be the highest thing on the tower.
Data cables aren't usually up that high, fortunately. Power cables, though, are. In some areas high tension towers carry a ground wire between the peaks of the towers for lightning protection. It's impressive to see those systems take repeated direct hits without the lights even flickering. I've seen that in Florida.
Worst case is probably is an AM broadcast station where the tower is isolated from the ground at the base. WSM in Nashville TN is like that. They had a pipe ground vaporized and windows blown out in a lightning strike in December 2019. They lost the tower lighting and some transmission components were damaged, but they apparently stayed on the air.
The Empire State Building takes about 25 lightning hits a year. I wonder what their lightning protection looks like.
Clearly you have never seen a phone line fried by a direct lightning strike before: the cable vaporizes and blows up the ground over top of it. Direct strikes are rare enough that most people will never see them. On overhead lines the neutral and communications strand are grounded and will take most of the strike over the twisted pair communications cable. Underground cables have some benefits by being in non-conductive conduit, but none of that matters if it's a direct strike. All insulators will break down in a strong enough electric field.
There's also the issue of ground bounce. A lightning strike near a house will feed back into the telecommunications and power equipment via the ground rod/plate. I've had experience with plenty of modems getting fried over the years. Some places are just lightning magnets.
