Visit Our UNIX and Linux User Community


General Proxy Question


 
Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers General Proxy Question
# 1  
Old 09-17-2001
General Proxy Question

This is quite a general question:

I am trying to detect whether people accessing my network are using a proxy server. This is *not* to ensure that web pages are not cached!

The only way that I can think of doing this is to intercept at packet level and examine the source port for high-numbers. But even this is no guarantee. Humph.

Does anybody have any suggestions. The solution must be automated, ie. I can't rely on users filling out a form correctly!
# 2  
Old 09-25-2001
No suggestions. I cannot think of any 100 percent reliable way to check this. Proxies, from the client perspective, look the same as clients. As you suggest, high port numbers are not an indication of a proxy server. Clients use high port numbers as well.

You might be able to guess proxies from large companies that direct the vast majority of traffic thru proxy servers by a study of the IP addresses of the connections. This would be a good guess for large organizations. You can also tell clients that are more-than-likely not proxied because of the hostname, i.e. the DHCP names of clients with Roadrunner, @Home, etc. This would be intelligent guessing (at best) and incomplete.
 

Previous Thread | Next Thread
Test Your Knowledge in Computers #610
Difficulty: Medium
Compared to Python, Perl has a relatively small Comprehensive Perl Archive Network (CPAN) library.
True or False?

10 More Discussions You Might Find Interesting

1. Programming

General question about learning Python

I am planning on taking a class in Python. My choices are 2.5 or 3.0. Which version should I choose? I am getting the impression they are two separate paths. thanks. (5 Replies)
Discussion started by: djehresmann
5 Replies

2. Shell Programming and Scripting

General question about passing variables among shell scripts

So this is something I've been wondering how to do for a while. Suppose I have two shell scripts a.sh and b.sh script a does some function and outputs to a varable $x . I would then like to take $x into the second function, b.sh, and do a function on it and create some output. So how do you pass... (3 Replies)
Discussion started by: viored
3 Replies

3. UNIX for Dummies Questions & Answers

General question about folder level permissions

How is the level of access on a particular folder determined? I have heard (its just hearsay so am not particularly sure of it) that the access a particular user/group has to a low level directory is also affected by the level of access granted to the user/group on its parent directories. e.g. ... (1 Reply)
Discussion started by: jawsnnn
1 Replies

4. Linux

General compression question

I am looking for an alternate solution other than gzip or bzip2 to compress files that are 3 to 4 GB each and will be hundreds per day. Aside from increasing storage anybody found a good tool? (5 Replies)
Discussion started by: mykey242
5 Replies

5. Solaris

General question about configuring DHCP on Solaris

Dears, my question is that possible to configure any server to work in solaris zone i mean any server cos i read that DHCP can't be work on solaris zone is that real or not Best Regards Alexander Corvinus (4 Replies)
Discussion started by: corvinusbsd
4 Replies

6. UNIX for Dummies Questions & Answers

General Programming Question

Experience level : New to programming in Linux. Forgive my noobiness in this context with regards to programming, language or grammar. Some Background info : I have seen a lot of programs which I use (Modo and Maya especially) which can use a command line to run the different parts of the... (2 Replies)
Discussion started by: snd321
2 Replies

7. UNIX for Dummies Questions & Answers

Executable directory general question

This may be a dumb question (but this is the UNIX for Dummies Q&A forum :) But I'm wondering, what is the purpose of a directory being given execute permissions? I can't execute a directory, only files, right? If I make a directory executable, the files inside still won't execute unless I give... (1 Reply)
Discussion started by: FredSmith
1 Replies

8. Shell Programming and Scripting

general question?

Perl, Python, and PHP are these languages easy to use? Are they command line or are they part of a GUI? (2 Replies)
Discussion started by: wmosley2
2 Replies

9. UNIX for Dummies Questions & Answers

General Question

Hi, I've been racking my brains trying to remember, but, whats the command to change the default shell? I'm currently always in the Korn shell and I want to start out in the Bash shell. I'm running a variant of BSD I guess in Mac OS X 10.2.2 and Mandrake. Thanks. ccindyderek:confused: (4 Replies)
Discussion started by: ccindyderek
4 Replies

10. IP Networking

General Proxy Question

Firstly I must apologise; I have posted something similar in the "general UNIX newbies" forum; but in reterospect I think that it's more appropriate here. Anyhoo; I am trying to detect whether people accessing one of my servers are coming via a proxied connection. I must add that this is... (1 Reply)
Discussion started by: sam_pointer
1 Replies

Featured Tech Videos