How can I simulate blocking RTMP over port 80 on Windows?
- by Christian Nunciato
It seems like this should be so simple, but since this isn't my area of expertise, I'm having a hell of a time figuring out how to do it.
Basically, I have a Flash app and I'm connecting to a Flash Media Server to stream some content. The URL I'm using to do this, for example, looks like this:
rtmp://someserver.com/some/path/mp3:somefile
Everything works -- but that's sort of the problem. When I'm trying to do is simulate my users attempting to play back my media under more restrictive conditions than the ones I have here (i.e., none) -- namely being stuck behind firewalls or proxy servers that block access to RTMP streams.
Flash, according to Adobe, is equipped to handle proxy servers and firewalls automatically, like so (from the docs):
When you do not
specify a port number in an RTMP
address, Flash will attempt
to connect to port 1935. If it fails
it will then try to connect to port
443; if that fails, it will try port
80. [And if that fails, it will attempt to connect via RTMPT (i.e., HTTP tunneling) on port 80.] So no coding is required to access ports 1935, 443, or port 80 if you do
not specify a port in the RTMP
address.
The problem I'm having is setting up a reliable environment in which to test that this behavior actually happens. I'm on a Windows machine, for example, so with Windows Firewall, I can block certain ports and protocols (1935, 443), but I don't want to block port 80, because the final fallback protocol (RTMPT) is supposed to run on port 80, and Windows Firewall only gives me enough granularity (as far as I know, anyway) to block "all outbound TCP traffic to remote port 80" -- that is, I can't, apparently, block "all outbound RTMP traffic to port 80" while leaving RTMPT traffic to port 80 unaffected.
My understanding thus far is that I'll probably need to set up a proxy server to do this. Is this correct? Or is there a simpler way (on Win 7, at least) to filter out RTMP to 1935, RTMP to 443, RTMP to 80, but still allow RTMPT to 80 (where all four hostnames are identical)? And if I do have to set up a proxy server, what's the simplest way to go on Windows? I've set up WinProxy, which seems a bit janky but apparently works -- but then what I can't figure out is how to tell Windows to force all TCP traffic (including RTMP, RTMPT and HTTO) through this proxy server so I can turn around and reject the requests for RTMP.
Any help would be hugely appreciated. This isn't my realm of expertise and I've alreasdy spent more time on it than I probably should. :)
