I am currently in touch with a few HTTP proxy installations. As every time when troubleshooting network issues, I am looking at Wireshark on the network and trying to understand the different packets.
Here is a short overview of the differences between HTTP requests that are sent directly to the destination and HTTP requests that are sent via a proxy. Wireshark screenshots and a downloadable pcap round things up.
Continue reading At a Glance: HTTP Proxy Packets vs. Normal HTTP Packets