What you’re doing is very common. With so many open wireless hotspots around, it’s a temptation that’s frequently too hard to resist, particularly when you’re in need.
Yet resist it you should.
There are a number of problems that arise from connecting to an unknown but open hotspot.
Who owns it?
I don’t have a good approach to identifying the owner of an open hotspot.
The access point name or SSID that’s displayed is often a clue, I suppose, but clearly the person who set up the open hotspot you’re seeing didn’t bother to change the default name, so that’s no help at all.
There’s no reliable way to know for sure, or track it down, without more information.
So we have to assume it’s a poorly-configured access point in someone’s home or business.
Is connecting to it legal?
I am not a lawyer, and I don’t even play one on TV. This should not be considered legal advice.
My guess is, it’s very likely that what you’re doing is, in fact, illegal in most places. Naturally, laws and law enforcement vary greatly from location to location. I have no idea what the law is in your situation, but it’s safest to assume it’s illegal.
Is connecting to it ethical?
Even if it’s legal, using someone else’s internet connection without their permission is at least ethically questionable.
Even if someone leaves their internet connection horribly unprotected in the form of an open Wi-Fi connection, that doesn’t give you the moral right to connect to and use it. For example, they could be on a metered connection, and your use could cost them additional money. At a minimum, it could certainly slow down whatever they’re doing.
That they didn’t set things up properly themselves is no excuse.
At a practical level, though, legality and morality may not even be your biggest issue.
Is connecting to it safe?
When you connect to the internet, the owner of the connection can see everything you do.
Most of the time, you have no need to be concerned. Your “real” ISP (the one you’re paying money to, and the one who’s apparently coming out on Monday) typically doesn’t care. When you visit a friend, they probably don’t care. When you visit a coffee shop or hotel with free internet, they probably don’t care what you’re doing online.
But they might.
If the person down the street notices that his internet has slowed to a crawl at unexpected times, he will care. If he’s tech savvy at all, he might well be able to peek at what you’re doing. Even with a simple router or access point, it’s not that difficult to set up a PC with some software to monitor traffic. It’ll be complex data, perhaps difficult for a lay person to interpret completely, but it’s easy to watch and easy to capture.
Let’s consider two additional risks: malware and liability.
Malware: his, yours, and theirs
You’re exposing your computer to an unknown network.
Since that network has no wireless password, it’s likely the person operating it is less technically savvy than you are. By connecting to their network, you’re about to trust that they’ve set it up properly and securely. The one data point you have says that’s not very likely.
You’ll be exposing your machine to whatever he has on his network, malware and all. Even with a good firewall or VPN on your part, that’s just not a risk worth taking.
Looking at it from the other direction, what happens if your computer has malware and ends up infecting one of the machines on this unknown network? Once again, I’m no lawyer, but I’d expect it’s possible for liability issues to arise should you be discovered as the source.
There’s another even more troubling scenario. Hackers have been known to set up open Wi-Fi hotspots specifically to lure unsuspecting victims, monitor their internet traffic, and steal valuable information.
Just say no
As you can probably predict by now, my suggestion is simple: don’t do it. Just don’t. There’s too much risk, both legal and technical, if you head down that path.
If you must — if you just can’t help yourself or if you’ve discovered you’re connecting to a legitimate, legally accessible public Wi-Fi hotspot –then of course you need to treat it as you would any open hotspot: How Do I Use an Open Wi-Fi Hotspot Safely?
In your shoes, I’d wait ’til Monday, or perhaps visit a trusted friend, coffee shop, or library.