i got a message on my computer saying someone was scanning my ports danger it could be a cracker?

Question

what is a cracker and how do you guard against it

Answer 1

There are several possibilities:
One, if you know, you haven't installed a Firewall yourself (like Zone Alarm or Norton Internet Security or something else) then it's probably an advertisement and mostly a scam.

If you *do* have a firewall, and have just connected to the internet, then there is a slight possibility, that you got an IP adress from a previous user, that had some file sharing program open.
Other people who try to download will try his old adress, since some programs don't update their connections only every few minutes. So your firewall detects these connections, and because of the sheer volume of requests thinks, that you are under attack by a port scanner.

If you are already connected for a long time, then someone is trying to find out, if your PC has a vulnerable port open, abd your Firewall did a good job blocking this access.

For your question what a cracker is: A cracker is a malicious hacker.
Although in the media a "hacker" is always a bad guy trying to break into other computers, the correct definition would be cracker.

A hacker has fun trying out stuff with computers and other electronic devices.
If a person tries to break into his own computer to find out if it is vulnerable with the intend to make it safer or to make something cool, its a hacker.

If someone breaks into a computer avoiding security to steal data or disrupt services, its a cracker.

Compared to a car: your car's mechanic of your choice is a hacker. If he opens your car, and tunes it to go faster or installs a PC inside it and tunes your auto alarm to shout "Die! Thieving scum!" he is "hacking" your car.
The car thief who manipulates your alarm so it doesn't go off to steal your car is a cracker.

Answer 2

If you get a message about this kind of thing its usually just your computer's firewall advertising itself and telling you what a wonderful job its doing for you.

Provided you have it set up correctly, the default configuration should be fine, you have nothing to worry about and can even turn those messages off and let it get on with protecting your computer silently.

The cracker is likely to someone somewhere scanning to see if they can find a poorly protected computer they can take use to send spam or do some other nasty thing. So long as you have a firewall and its turned on you should be fine.

Merry Christmas!

Answer 3

It could be a hacker, or it could just as easily be your ISP pinging your machine to see if you are still online.

With more broadband connections around there are more instances of this, but its not really anything to worry about - even the standard Win XP firewall will block such attacks. A good anti-virus solution is more essential to guard your pc against visits to dodgy websites and to scan your incoming email.

Answer 4

I use McAfee and AVG for Virus detection. I've used Spybot on multiple computers over the years. I tried running it on this machine which I've done several times - wouldn't run so tried to download the latest version and AVG gave me a popup alert to remove it.

Answer 5

does your computer hook straight up to your modem?

if it does - then your pc has a public IP address.

get behind a router - the NAT will stop NETBios attacks, and other malicious activity.

your pc will be assigned a private address from the router and will be practically invisible on the net