Show me yours and I'll show you mine (IP addy)

I am staying in a hotel far, far away from home.

A few times the Internet went down and I had to call some 3rd party company that handles Tech Support for the hotel.

When I called last time, the (foreign sounding) tech kept asking, “Give me your IP address, so I can test some things.”

Isn’t it dangerous as heck to give out your IP address - especially if you are on a laptop without a firewall/router??

I told the tech “No way! If I give you my laptop’s IP address, then you’ll always know it and be able to hack my computer?!”

Is that true, or do I have wrong information?



If you have a local network then the IP addresses on that local network will be specific to that local network and will not be accessible from outside it. For example the computer I am on now has an IP address of and no one can access the computer using that address unless they are at another computer on my local network.

Public IP addresses are issued to ISPs and when you connect to the internet through them they issue you with an IP address belonging to them which is used as your IP address on the internet. When they are your regular ISP and you have a permanent physical connection to them they may issue you with a static IP address so that you will always have the same IP address. Alternatively they can give you a dynamic IP address which means that they swap all the IP addresses around every so often. With a wireless connection to your IPS or where you are away from home using some other way of connecting to the internet then you will only have the IP address for the duration of that connection.

Where people have a temporary IP address allocated to them to connect to the internet they are unlikely to know what that IP address is. The only reason those with a static address are likely to know what theirs is would be because they most likely specifically wanted a static IP address so that they can connect to their own computer themselves from other locations and so have gone to the trouble of looking it up.

I have no idea as to the IP address that my ISP has currently allocated to connect my local network to the internet.

What I have seen technical support people use when they need access to your computer in order to check things is to use one of the meeting web sites. They give you the site and a meeting id and when you get into the meeting you then have the ability to grant them access to see your screen and to work your computer using their keyboard and mouse. You can then watch what they do while fixing your computer. Once either you or they close the meeting they then have no further access to your computer.

No more so than visiting any website or connecting to any other service on the internet, your IP is visible to whatever you connect to. Do you trust every website you visit more than the tech support you don’t?

If someone knows your IP address, can’t they hi-jack your computer?

You make it sound like you can broadcast your IP address to the world and it’s no big deal? :-/

I thought one key benefit of home firewall/routers is the ability to mask your IP address and even change it regularly?


They can only hijack your computer if there is a vulnerability in either the operating system or an active application.

Whether you like or not, communication from your computer to the internet is generally travelling unencrypted over multiple networks all of which can see your IP.

Home routers typically use NAT to map the local network IP to your ISP allocated IP, and will only route incoming communications to your PC that you have initiated or have specifically routed. Whether your internet visible IP changes is down to your ISP not your router.

You do it every single time you get on the internet.

Tell me what you see here:

Should be the IP address of your external connection via your ISP.

There is a difference between putting your individual computer directly on the Internet with no firewall and running open unsecured services, and the way most people go about their daily usage - usually with a firewall, no un-necessary services running, etc. If you’re not offering any services like file sharing to the outside world, then there isn’t much to hack, is there?

I thought one key benefit of home firewall/routers is the ability to mask your IP address and even change it regularly?

True. Most people don’t get a dedicated IP address, they get one dynamically assigned by their provider, which their router then uses along with network-address-translation (NAT) to allow multiple computers to exist ‘behind’ the router, using that one dynamic IP to connect to the Internet.

That is pretty cool! :smiley:

If you’re not offering any services like file sharing to the outside world, then there isn’t much to hack, is there?

I thought - at least 5-10 years ago - that if you knew someone’s IP address that you could take over their PC?!


10 years ago the average PC often defaulted to having certain services turned on for convenience, in unsafe configurations with default usernames or passwords. Not so much the case these days. Personal firewalls on individual computers are much more common. Even if someone knew your IP address, most firewalls enforce some sort of connection control where if you initiate a connection with someone outside, it’ll allow that to happen. If someone from the outside tries to initiate a connection with you, it gets blocked unless you’ve explicitly made allowances for that.