From: grahn+nntp@snipabacken.se   
      
   On Fri, 2013-04-05, Pascal Hambourg wrote:   
   > Hello,   
   >   
   > glen herrmannsfeldt a écrit :   
   >>   
   >> I don't know either SIP or RTP in that much detail. Normally UDP runs   
   >> with a checksum. Most often, it runs over a hardware layer that supports   
   >> a CRC on the packet.   
   >   
   > The optional UDP checksum only covers the UDP pseudo-header, not the   
   > data payload.   
      
   Not true -- see RFC 768:   
      
      Checksum is the 16-bit one's complement of the one's complement sum   
      of a pseudo header of information from the IP header, the UDP   
      header, and the data, padded with zero octets at the end (if   
      necessary) to make a multiple of two octets.   
      
   How optional it is today can also be debated, I suspect. IIRC it's not   
   optional over IPv6.  And there's also UDP Lite.   
      
   /Jorgen   
      
   --   
     // Jorgen Grahn    O  o   .   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)