Curious

[jonf]

I've never had any networking problems with FSHost before so never bothered to do a port scan on that machine but just did yesterday and was curious about some of the ports it was listening with and these UDP ports were reported. Are the ones listed here that aren't part of the published list of ports to open just for local use? or can opening some of the ranges below possibly help some people out?

FSHost30       ->  1043  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  1050  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  1051  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  1209  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  1211  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  1212  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  2350  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  2351  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  9122  UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  20020 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  20171 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  23456 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  23457 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  32481 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  39613 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  40140 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  41348 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  44207 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  44963 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  49959 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  52787 UDP   D:\FSHost\FSHost30.exe        
FSHost30       ->  64721 UDP   D:\FSHost\FSHost30.exe        

[Russell Gilbert]

Yeah, I've seen strange things like this too.  I can assure you it's all DirectPlay doing those weird things, not FSHost.  The only port FSHost explicitly opens on its own is TCP 80, for the web access.

I think part of the reason for all the ports is the way DirectPlay communicates with other machines.  Sometimes when I was tracing a connection, I could see that machine A would send a packet out from his own port X (which was just some random port number, maybe in the high range) to one of the normal DirectPlay ports on machine B (maybe 2350, for example).  Sometimes the two machines would then settle on 2350, and both sides would send and receive on that port.  But sometimes they'd settle on the high-numbered random port instead, or one side would end up sending back to that high-numbered port while the other sent to 2350.  Anyway, it's all in the way Direct Play tries to switch to any port it can to find a good connection -- if it sees the other machine using some particular port, it sometimes tries to use that port locally as well.  The result is probably that you get a strange-looking list of ports being used by the program.

Well, that's my guess, anyway...

But you don't need to open any of those ports -- it probably wouldn't do any good anyway, since they're probably random.  DirectPlay is very good about always trying specific ports first, so the published list is all that's required.  If they're open and available on both sides, no other ports are needed.

Russell