Ian Kenefick said:
There is a lot more krud circulating the net to be worrying about
rather than legitimate (and miniscule) data performing a legitimate
and important function as in this case.
Although the "blips" going over the Internet is not a real issue,
keeping the session alive while transmitting nothing to the mail server
is important. There will be only so many resources that a host can
provide whether for a single host or a boundary host that passes off the
connection to a farm of hosts. Every connection takes resources. ISPs
will maintain some load capacity for their customers but rarely could
handle them all at once. The longer you maintain a mail session the
longer you consume those resources that some other user could be using
to get or send their e-mail. Leaving a mail session open without
transmitting any real data to it is hogging the resource. Think of it
in perspective. If you had a few internal users connecting to your
workstation which has a limited number of connects available and one of
them stays on for 10 minutes to transfer a huge file (which would
transfer in 5 minutes via e-mail but the other 5 is waiting to actually
get the file, or the file would transfer in 2 minutes to upload it via
FTP and a few seconds for the e-mail) than the impact is noticable to
the other users that cannot get a mail session because they cannot get a
connection. Now up the scenario to you running a server with hundreds
of users trying to use its larger but still limited resources. Many
users hogging the connections means others may not get connections. Now
up the scenario to a nationwide ISP with MILLIONS of users. The ISP
doesn't have enough resources to handle more than a certain percentage
of concurrent load from their customers for e-mail. Yeah, their
capacity is a lot bigger but then so is the size of its customerbase.
You don't think you would get pissed if everyone going through the
revolving door at the store momentarily paused in the door and made you
wait? Get in and out quick. (Also, set your mail poll interval to
something realistic based on the level of your e-mail traffic. No one
needs to poll at 1-minute intervals!)
Sending huge files via e-mail is stupid, anyway. POP3 and SMTP are
*not* file transfer protocols. Mail servers will be choked per
connection for bandwidth to ensure a decent level of response for all
the other mail sessions for other users. There is no recovery, no
resume, or other features of real file transfer protocols. Rather than
compress the file for transmission, using e-mail will ENLARGE the size
of the file transfer due to encoding of attachments into plain-text
sections within the e-mail (figure about 30% larger, or more). This
also adds to the transmission time. Upload the file onto a host for
online storage somewhere, like a personal web page, online file services
(some are free, like Yahoo Briefcase), your own FTP server, or whatever,
and put a link to it in your e-mail. Then your e-mail is puny and
transfers quickly and reliably, you don't assault the recipient's
mailbox and possibly consume its disk quota to render it unresponsive to
further e-mails, you don't insult the recipient by making them wait for
a huge e-mail containing an attachment they may not want, and the
recipient can download the file whenever THEY choose to do so. Be
polite and give them a link to your huge file.