Port 80 and firewall/proxy
Scott C. Best
sbest "at" best.com
Wed Oct 6 01:04:00 2004
Heya. In addition to the firewall you have at work, all
web-traffic (ie, HTTP) is probably passed thru a web-proxy first
(a very common setup for corporate networks). Unfortunately,
a VNC Viewer is not "HTTP-proxy" aware.
At a high level, then, you have two choices:
1. Try another port instead of 80. My favorite is 443, the port
used by HTTPS (in which the data content is SSL-secured, so
any packet-inspection a firewall/proxy might want to do is
pointless anyhow). Many of those common corporate network
environments will mistakenly allow anything out as long as
it's headed to TCP 443, regardless of whether it is really
in HTTPS format or not.
2. Try using a second application to "bypass" your workplace
firewall/proxy. HTTPort (http://www.htthost.com) looks to be
a pretty good one (though I never used it myself). It has the
advantage of not requiring you to install anything on the
target machine, just a "HTTPort client" on your VNC Viewer
machine. Other solutions, such as common "tunneling" applications
like SSH or Zebedee, require their own client alongside your
VNC Viewer as well as their own server alongside your VNC
Server. For many advanced VNC users, this is no hassle at all.
For new users ... it can be a challenge.
Hope these suggestions help! Other ideas VNC users have
had over the years regarding this topic can be found here:
BTW, please note: doing any of this could be contrary to
your workplace network security policy. And some managers take
such violations more seriously than others.
> Hey guys.
> I have a little problem.
> I've read all the posts regarding proxys and firewalls, and tried what I've
> found, but it still won't work. Here's the deal:
> I've got a computer at home that's behind a router. I want to be able to
> control this computer from work.
> At work I have no rights to open ports, and the computer uses a proxy.
> Port 80 is open because WWW works.
> I've set the vnc server to port 80, and I forwarded port 80 on the router to
> the vnc PC.
> I asked a friend to connect to my vnc using vnc viewer: <ip>::80, and it
> However, from work it does not. I've tried the negative port number (-5820)
> and it doesn't work either.
> Does anyone have any idea on what can be done to solve this?
> Any help is greatly appreciated. Much thanks
> / Magnus