Proxy Servers Information

Hi there, experts!

I have three questions regarding proxy servers, they are all related and I'm giving 500 points to the person who answers correctly.

I would like to know if there is any way and how to find out detailed information about a Proxy Server.

For instance, if you go to, you will see a list of proxy servers with  extra information such as the "type" of server. How can a program scan a server to see if it is "transparent", "anonymous", "high anonymity", etc.?

Specific questions:
Can I use Winsock to obtain this information?
How can I know which port I have to use to connect to the Proxy Server?
How can I know if the IP address that I'm pinging or connecting to is actually a Proxy Server?


Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Here are the different proxies and the properties.

Transparent Proxies
They do not hide information about your IP address:

HTTP_VIA = proxy IP

The function of such proxy servers is not the improvement of your anonymity in Internet. Their purpose is information cashing, organization of joint access to Internet of several computers, etc.

Anonymous Proxies
All proxy servers, that hide a client’s IP address in any way are called anonymous proxies

Simple Anonymous Proxies

These proxy servers do not hide a fact that a proxy is used, however they replace your IP with its own:
HTTP_VIA = proxy IP

These proxies are the most widespread among other anonymous proxy servers.

Distorting Proxies

As well as simple anonymous proxy servers these proxies do not hide the fact that a proxy server is used. However a client’s IP address (your IP address) is replaced with another (arbitrary, random) IP:

HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = random IP address

High Anonymity Proxies
These proxy servers are also called "high anonymity proxy". In contrast to other types of anonymity proxy servers they hide a fact of using a proxy:

HTTP_VIA = not determined
HTTP_X_FORWARDED_FOR = not determined

>>Can I Use winsock to obtain this information?
Well you need to access a remote system and see what info is available in the packets.

Why not use any of the free checkers out there?
You could use your own web server if you have one to check the variables described above.

>>How can I know which port I have to use to connect to the Proxy Server?
Generally it will be supplied to you with the proxy address, if not 8080,3128 & 80 are common ports.
The port is set in the proxy config and can be anything this is the problem with open proxies admins just too dumb to know or too lazy to change them.

>>How can I know if the IP address that I'm pinging or connecting to is actually a Proxy Server?
From a simple ping you can not tell, a ping gets a reply from a server. It does not reveal any information about HTTP/FTP/PROXY services etc.
You can simply attempt a proxy request by supplying any ports dicovered as a proxy to the winsock control and attempt to access a site with the proxy active.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
NoviceASPAuthor Commented:
Your explanation was good enough to clarify my doubts and answer my questions.
Thanks a lot!
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Programming Languages-Other

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.