Low-level: Conversing with a proxy server....

I’m working on a client app running on an embedded system. It does all of its networking via sockets, making it’s own HTTP headers and such.

Through watching the packets going out of my machine, I have been able to determine that in order to reroute through a proxy server you need to attach a “Proxy-Connection: Keep-Alive” parameter to all of your requests. But the only proxy server I have to connect to are any of the public ones you can find on the internet–none of which require authentication. And, I can’t seem to find any documentation about what data needs to be traded, in what order, with what level or type of encryption, etc.

The company we are building the app for have also said that they are using “iPlanet” as their proxy software, and that it requires a “pack file”–but google tells me nothing about “pack files” and only reveals that iPlanet has been discontinued.

This is a rather specific question but, does anyone know of any sources that would have information about the above?

Ah… good fun.

You’re going to want to familiarize yourself with the relevent RFCs. I once wrote my own, very basic HTTP server implementation using only the RFCs as a guide. They’re pretty straight-forward to read and considered gospel (for well-established protocols, at least) when developing TCP/IP based apps that you want to be standards-based.

Proxy server support was introduced with HTTP v1.1, so read up a bit on RFC 2616.

Good Luck!