>  Please don't do that. The overhead to check for no mail is trivial.

That is not correct. Simple benchmarks will show you that checking for
"no   new   mail"--not   "no   mail,"   which   is   not   technically
correct--creates substantial CPU load. For hosting providers, it is an
undeniable cause of instability on client and server.

> In business, a "communication" often takes four or five retries.

Huh?  It may only appear to take four of five retries _if_ people make
the utterly wrong assumption that e-mail is a real-time medium. Due to
the size and number of messages that can be transmitted to one account
in  a  given  period,  Users cannot be led to expect that SMTP latency
will  be  less  than  5  minutes,  and  their  POP3 checks must be set
accordingly.  Anything  else is suicide for client-side stability (the
main cause of duplicate messages is overlapping POP3 checks).

For  users  connecting  over  POP3 to the local LAN, while it may seem
"cool"  to  try  to  fool  them  into  thinking they're using Exchange
internally   by   scheduling  1-minute  checks,  you  must  do  proper
benchmarking  to  determine  whether  a server's traffic patterns--and
concurrent  resource utilization by non-mail processes, which is often
the case in small shops with one file/mail/db box--are up to the task.

For  the  above  reasons,  for  a  hosting  provider that's one of our
clients,  we  built  a  solution  a couple of years ago that would not
report  new  mail if checks were performed more frequently than very 5
minutes  (it  will not even re-check the credentials). The only reason
this  service is no longer in use is that they scaled out their server
farm to handle more traffic.

--Sandy


------------------------------------
Sanford Whiteman, Chief Technologist
Broadleaf Systems, a division of
Cypress Integrated Systems, Inc.
e-mail: [EMAIL PROTECTED]

SpamAssassin plugs into Declude!
  http://www.mailmage.com/products/software/freeutils/SPAMC32/download/release/

Defuse Dictionary Attacks: Turn Exchange or IMail mailboxes into IMail Aliases!
  
http://www.mailmage.com/products/software/freeutils/exchange2aliases/download/release/
  
http://www.mailmage.com/products/software/freeutils/ldap2aliases/download/release/


To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html
List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/
Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/

Reply via email to