How does msftconnecttest.com/redirect work?

I just wondered how exactly msftconnecttest.com/redirect works.

• Is this feature built into every router?
• How else would a link redirect you to a login page if you first need to login to resolve the link?
• Are there any alternatives out there?

It also works on Android, so i don't think it's just built into Windows.

Solution 1:

Is this feature built into every router?

First off, this isn't the feature. There's nothing special about this URL at all. The actual "feature" is that the router redirects all HTTP URLs to the login page; this just happens to be one.

No, most routers don't have this "feature" because most routers don't have any kind of web login page in the first place. I mean, it's really not part of a router's job description.

(And if you're on a network which does have such a login page, it's more likely that it is imposed centrally at the network operator, not at each individual end-user router.)

How else would a link redirect you to a login page if you first need to login to resolve the link?

When there's a login page, you're not actually "resolving" the address to its real destination at all. Instead, the router (the one which implements the login page) intercepts all DNS requests and always gives you a fake response pointing at the router itself.

It also intercepts all HTTP requests, always returning a fake "redirect" response that again points at the login page at the router.

(The link you have actually expects to be intercepted like this. Its real response just leads you to the MSN News webpage, not to any login page.)

Are there any alternatives out there?

Plenty. There is nothing special about this URL at all, except the fact that it is deliberately plain HTTP and not HTTPS. The network doesn't care about the "msftconnecttest" domain, and it doesn't care about the "/redirect" part either.

So when you're dealing with a network that has a web-based login page, usually it'll just intercept literally every HTTP request and redirect all of them to the login page. For example, if you visit neverssl.com or echo.opera.com, it'll get intercepted all the same.

Really, that's how such things always used to work in the first place. It was actually a much later addition that the OS began using these dedicated URLs to probe for redirects. Before that, you actually had to open some random website yourself.

(If you're asking about URLs that an OS uses for this specific purpose – yes, macOS has its own, Android has its own, Fedora Linux has its own, etc.)