Actually this is likely Sky's opt-in adult content filtering. It really isn't mandatory.

Any content blocking is prone to false positives and people will learn that eventually.

Sky's filtering is now opt-out:

> What we’re doing now is simply making sure that the automatic position of Sky Broadband Shield is the safest one for all – that’s ‘on’, unless customers choose otherwise.

src: https://corporate.sky.com/media-centre/our-blog/2015/sky-bro...

When the whole opt-in opt-out thing hit the news I remember all the press was insisting it was opt-in. Simply insisting, then basing their arguments off that.

Not mandatory though, that's most the important thing.

You can get the client to disable this via the My Sky page here: https://secure.sky.com/mysky-homepage/indexb

This is opt-in so they clicked a button somewhere when Sky asked them if they wanted adult content blocking.

If anyone opts in to blocking; it's their funeral. It doesn't work. Sky's blocking even kills ThinkPad wiki.

Sky announced a couple of weeks ago that they intended to turn on their filtering by default. Maybe that's now happened.

Source: http://www.bbc.com/news/technology-30896813

Yes, it has been, from my metrics at least - with predictable results! (Seems to be a phased/tranched rollout.)

Don't get CloudFlare to budge you to another IP, you'll never know what may or may not be listed - most of the content on the default filter is not porn. This is Sky's problem, not CloudFlare's.

It's deplorable, but entirely predictable (and they were repeatedly and loudly warned!) that innocent bystander sites have been blocked by the censorship on Sky's broadband network that people haven't even asked for.

Have you perhaps considered legal action against Sky?

You may also want to let them know, but they can't admin the filter themselves (last I heard), so can't whitelist you, and the equipment they have cannot proxy the site on their list without also affecting yours. (That you share an IPv4 address is not itself an issue with CloudFlare.)

Don't mind me, I'm just getting snacks. This is going to get worse.

> Have you perhaps considered legal action against Sky?

This is the real, correct solution but seems unlikely. The OP said his client is unable to shell out the extra $20/month for SSL on Heroku so it seems unlikely they'll want to pay for lawyers required for legal action :(

This precisely fails to address the actual problem: his site is blocked for other users.

It seems that for the three people I have contacted, they have no recollection of being opted in to this adult blocking service

It asks you when you first connect the router. I suspect most people you have contacted are likely to have subconciously (or thoughtlessly) opted in.

If you let me know the URL, I can test from here as I'm on the end of a Sky connection without the opt in blocking so that would confirm if it is that or not.

A lot of people get technicians in to install the hardware, their default mode is to just next,next finish until the router is ready. Chances are it's the technicians themselves turning on the blocking. Not in a malicious or tinfoil hat way, just out of a desire to get the job done quickly

I can't let you know the URL, but http://medfirstalert.com/ is one of the other seemingly okay domains on this IP

That's fair.

The domain above resolves fine with and without the block: http://i.imgur.com/AIqtrxF.png

DNS cache was flushed between each hit.

If you have an engineer set up the router, they may just click though the screen as part of the set up, or bypass the traditional set up to save time.

Probably because the government told ISPs that opt-in should be the default.

One of my hobbies is arguing with reviewers about these sort of things on amazon. Its amazing the crap they come up with.

Squirrels act as inductors in DC circuits. Only once though. There's a high current surge that drops to zero as they turn rapidly into a carbon resistor!

We had a number of network outages at Apple due to squirrels inserting themselves in the NOC's power lines.

Note to self: Don't design any circuits that incorporate these animals. Squirrels make terrible fuses.

So true.

We had a different problem. They chewed through the fibre cables between our offices to get the fiberglass sheath for their nests. Eventually they ran Ethernet underground because they'd have broken it again in a couple of weeks.

Whereupon: Moles :-)

a bit like the NED Noise Emitting Diode - makes a lound noise once

Having sat there, as a teenager, with a whole bag of 1N4148s and a mains test block, can confirm :)