How to watch network traffic? A la packet sniffing or web debugging proxy?

http proxy debugging traffic
cwd picture cwd · May 22, 2011 · Viewed 13.6k times · Source

So when I am debugging my web applications and such, I've used the Charles web proxy and debugger and love it. It's so nice to see what's being sent and received via port 80 and 443. I can see all the resources loading, not just from the "browser" per say, but also flash applications. I can also see how the calls are being made, and it pretty easy to reconstruct them. It's a great debugging tool and I love it.

So I'm wondering two things:

First, I'm wondering is if there is something similar I can use to watch traffic that might be coming though on other ports. I guess some desktop applications will use the internet, but not necessarily via http / https requests. I remember looking at some security tools a few years ago - there are a lot of security tools out there, like kismet / etherCap, ethershark, etc - is there one that does what I'm describing in an easy and intuitive way?

Also, I'm wondering if I am using my iPhone / iPad / Android device, how can I set up a proxy through my computer so I can watch the http/https requests that the device makes?

Found the answer to that one here: http://www.ravelrumba.com/blog/ipad-http-debugging/

I'm mostly on a Mac so anything that is Mac friendly would be extra helpful.

Thanks!

Answer

AndrewF picture AndrewF · May 22, 2011

I believe you are looking for Wireshark. It allows you to monitor the network interface on your machine and be able to tell you sent/receive packets as well as their protocols. It also has a protocol decoder that can be used to get Layer 7 information about a IP stream. You can also do a "Follow TCP stream" which allows you to view the entire conversation of that connection. It's based on libpcap (Packet capture) which the built in tcpdump also uses.

The only downside for you web developers is that if you're using SSL encrypted sessions, you can't decode it. The endpoints of the SSL session are "above" (using OSI model) the layer at which wireshark (and similar tools) operate.

Related questions

How do I make HttpURLConnection use a proxy?

If I do this... conn = new URL(urlString).openConnection(); System.out.println("Proxy? " + conn.usingProxy()); it prints Proxy? false The problem is, I am behind a proxy. Where does the JVM get its proxy information from on Windows? How do …

Read More
How can I use an http proxy with node.js http.Client?

I want to make an outgoing HTTP call from node.js, using the standard http.Client. But I cannot reach the remote server directly from my network and need to go through a proxy. How do I tell node.js …

Read More
Using an HTTP PROXY - Python

I familiar with the fact that I should set the HTTP_RPOXY environment variable to the proxy address. Generally urllib works fine, the problem is dealing with urllib2. >>> urllib2.urlopen("http://www.google.com").read() returns urllib2.…

Read More