>Unfortunately, the numbers I got appear to suggest that switching
>to VERP deliveries would increase our bandwidth consumption by as
>much as 40%. Here's how I arrived at that number, for anyone who
>wants to follow along and correct my assumptions.
I would think that your labor costs savings would be able to offset any
increase in bandwidth costs when using VERP. That is, we have a part-time
person to help subscribers that are having problems, and the vast majority
of those problems are people having trouble getting unsubscribed.
If we were not using VERP single delivery, that would most likely be a full
time job. That's because with the traditional BCC method, the subscriber
never sees any clue as to which email address they are subscribed under.
We put in the subscribers email address in the To: line of all announcement
lists whenever we are doing VERP. I have seen other lists drop in the
email address at the bottom of messages too, and both might be advisable.
As long as you are sending a unique message anyway, why not ?
We use Exim as our MTA, which has the ability to do VERP, as well as
manipulate headers so that we can put the receipents email address in the
To: line. We use VERP on all our small and or in-frequent lists. For our
bigger lists, we use the traditional mailing list method for all the large
domains, and VERP single delivery for the rest of the list. With AOL for
example, I don't think VERP helps that much, since AOL handles bounces ok,
and the email ends up in the mailbox for the "screen name" that the person
is using, so they are rarely confused as to which address of theirs is on
And with the rapidly falling price of bandwidth, I expect we will be using
VERP single delivery on every single piece of email. Both for the easy
handling of bounces, and eliminating the confusion of which email address
is on the list,from the subscribers point of view.
That's my 2 cents :-)
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