pendent blocks, which are  not guaranteed to reach the other
end. Even when they  do reach the other end, they are  not guaranteed to be
error free. Data  transfers are atomic, one datagram at  a time. Reading
only  part of  a  datagram discards  the  rest, so  that  the following read
operation  will  act  on  the  next  datagram.  The  advantages  are  in
simplicity (no connection  setup) and performance (no  error checking or
error correction). 
</p>

<p>
Note that although no guarantees are made, these 