 is merely one way to satisfy these requirements,
and there are alternative implementations as well.  For instance,
instead of associating separate socket connections with each remote
environment, an application might instead label each message with a
sender identifier; instead of looping through a table and sending a
copy of a message to each member of the replication group, the
application could send a single message using a broadcast protocol.</p>
      <p>The quote_send function is passed as the callbac