b8e6c10d   
   From: roy@panix.com   
      
   In article   
   ,   
    David Schwartz  wrote:   
      
   > On the Internet, a lot of connections pass through firewalls and   
   > transparent proxies that find it very hard to DTRT with half-open TCP   
   > connections.   
      
   This is a specific case of the more general statement, "This which are not   
   commonly used tend to be broken".  Forget about firewalls, I wouldn't be   
   surprised if you found kernels which can't handle simplex connections.   
   It's just not something that's commonly done, so it doesn't get a lot of   
   testing.   
      
   We've found the same is true for TCP urgent (i.e. "out of band") data.  I'm   
   currently working on an application which depends on OOB data to implement   
   keepalive messages.  In theory, the design is fine.  The problem is, we   
   keep running into real-life examples of systems with broken   
   implementations.  Not to mention that the security world seems to have   
   gotten into its head that urgent data is a security issue and we're seeing   
   firewalls which are administratively configured to block any TCP packet   
   with the urgent bit set.   
      
   Bottom line: stick to the mainstream features, because they're more likely   
   to work in the real world.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)