ned.freed@innosoft.com
Mon, 24 Jan 2000 11:40:44 -0800 (PST)
> We seem to be ascribing different meanings to partial delivery. If we fail to
> deliver all the pages in a fax, returning this information to the sender will allow
> the sender to retransmit the missing pages. The same is true for a multipart
> message when on or more of the parts were not successfully delivered.
Actually, the differences are even greater than this. The FAX world's issues
with partial delivery have to do with the analog lines used and the resulting
possibility that some portions of a transmission can be garbled. In such
cases there is a reasonable expectation that retransmitting will help.
This is not the case in the email world. Partial losses due to garbling of
message content on analog lines are extremely rare. Losses in the email world
generally are the result of some system being incapable of handling some
particular media type. And in such cases retransmitting the same message to the
same address is a total waste of time.
However, at least one of the goals here is to standardize a way to report
tranditional FAX errors when gatewaying from email to FAX. So I basically
see the issues of describing FAX errors as a subset of a much larger and
more complicated problem this proposal is attempting to address.
> It is true that the criteria for declaring a particular page not to be successful
> in fax are not defined in the standard and thus each manufacturer has defined their
> own. This accounts for the variability noticed by earlier commenters. In any case,
> we are dependent on the interpretation of the particular manufacturer for the
> decision as to whether it was successful or not.
Then perhaps we should carry this over to the present case and allow some
leeway in what constitutes an error when gatewaying.
> My personal take on this is that the delivery information to be returned should be
> useful and allow appropriate action to be taken. Sometimes we may have to
> retransmit the entire message even when we know where the error occurred because it
> is not feasible to only retransmit that part of the message.
Perhaps this argues for focusing on reporting more about how to deal with the
error than the specifics of the error itself. In the FAX case there should be
something to indicate retransmission would help. In the case of a dropped part
because the system cannot deal with it an alternate address would perhaps make
sense. (SMTP used to have some redirect facilities, but they have fallen into
disuse.)
Ned
This archive was generated by hypermail 2.0b3 on Mon Jan 24 2000 - 21:50:59 IST