Hi, I'll prefix this by saying that I'm not a network admin. My comments below are based on my experience with a similar setup... On 19 October 2010 02:21, Justin Richards wrote= : > > My question is :- > > Can my network administrator stop other traffic (other than http > requests) =A0from using port 80 and 443. For http, yes. But unlikely. It's probably too expensive in terms of firewall hardware to do this. (but see below re: proxies) For https, not really. Because the data is encrypted so no-one (except at the other end of the connection) should be able to tell what you are sending > > My results indicate that he can as I could NOT ssh on port 80 and when > I try to use port 443 (even thou I know the service is not running) it > immediately reports "Network Error: Connection refused". =A0The response > seems too quick for it to have actually tried the connection and > appears to be getting blocked locally. If your router has the port open, but there is no service running inside your network, then this may be expected. If the router was silently dropping packets, then you would most likely get a timeout after some delay. > > The strange thing is, I know I can get out on 443 with VNC (but not > port 80 as I have tried this) so I guess VNC traffic looks like > http(s) traffic. I expect you have a proxy at work to connect to the internet? In that case you probably can't get a direct connection out of work on port 80. All HTTP traffic will go via the proxy, and in that case it has to be real HTTP traffic, otherwise the proxy won't understand it. (You *can* tunnel other protocols through HTTP, but that's another story) Port 443 is a different matter. The proxy cannot intercept this traffic because the secure connection can only be created with the desitnation website, not your companies network infrastructure. There are 2 ways I'm aware of that HTTPS traffic may be leaving your company network (there are possibly lots more methods - these are the 2 I know about): 1) All outgoing traffic on port 443 is allowed 2) All outgoing traffic on port 443 goes via the proxy using the HTTP CONNECT method In option 1), you should be able to use ssh on port 443 In option 2), you should be able to use a proxy-aware ssh client (such as putty) to get to your server (it will issue a CONNECT command to the proxy, and that will connect you to your home server) >From your previous comment about using vnc over port 443, it sounds like you have option 1). So I would try running ssh on port 443 and attemtping the connection again > > So it looks like I am back to dynamically reconfiguring the modem > using software control which is sad as ssh looked so promising. Don't give up yet! If you have another internet connection (such are 3g) I suggest you test with that on your laptop first. The advantage is that you can be at home with both the local and 'remote' ends of the connection, which makes debugging much easier. Once you have that working, you can try it again from work. Matt --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .