Port Scanners

Have you look at NMAP (nmap.org). This is what NMAP does.

.... Thinkpads_User

T1 Online Port Scanner lets you scan a range of ports:
http://www.t1shopper.com/tools/port-scan/

If you are talking within your lan, you my have to use a different tool..

Whois / TCPView - http://technet.microsoft.com/en-us/sysinternals/bb795532

HTH,

Kent

For the LAN there are also some other free windows tools that are fairly easy to use:

Advanced IP Scanner
http://www.advanced-ip-scanner.com/

Network Scanner
http://www.softperfect.com/products/networkscanner/

most online port scanners will only let you scan your own ip. this is to prevent you from using them to attack others.

can you tell us more about your situation ? we might be able to give better advice. what are you trying to check ? software known vulnerabilities ? open ports ?

also beware that software that list vulnerabilities by checking software versions are plain useless and will both make you work on useless upgrades and forget about what security truely is. always having the latest version of apache facing the internet is completely dumb if your apache runs as root on a machine that is not properly isolated from your lan.

@thinkpads : does nmap provide online port scanning services ? open for scanning any IP ? i'd be more than happy with an URL if anybody provides such a service

The last time I used Nmap, it was a piece of software to install. I had it on a Linux system. ISP's do NOT like port scanning, so I did not use it much. I offered it as an option, and because it was/is free.

.... Thinkpads_User

so much for my hopes

a solution for a port scan could definitively be to run nmap from a remote location, but nmap does not do much when it comes to vulnerability checks. nessus does a good job at presenting known vulnerabilities. http://www.qualys.com is likely based on nessus and will do remote scans. i don't think the free version will let you scan any IP, but i did not give it a try.

anyway since the author does not interact with this thread anymore, it will be difficult for us to help more, and coming up with a bunch of tools probably won't do.

if the author is looking for a commercial service, then any of them will do since they are almost all based on the same free software tools we are used to. they only tend to differ in the way they present the results. this include costly security audits as well for the majority of them.

I have found my own languard scanner, which seems to work for 25 hours.

I've requested that this question be closed as follows:

Accepted answer: 0 points for LateNaite's comment #a39485708

for the following reason:

Found my own scanner, which worked well.

Found my own scanner

as far as i know languard does not provide any ONLINE scanning services (but the scanner is a nice very customisable tool). if it does, would you care to share ?