Michael,
True, that added overhead does affect transmission time, though it
would not show up in the file size of an email attachment. The
protocol overhead would apply to whatever data that was being sent,
binary or not.
Curt
W. Curt Deegan
Boca Raton, (Southeast) Florida
Michael Hawkins wrote:
Beyond this overhead, add the overhead that TCP/IP protocols
induce as well. The 8 bit data effectively becomes 10 bits when
averaged out.
Steve,
Email clients and servers only handle character data which is 6 bits.
Binary data is 8 bits. To send binary data files the 8 bit data is
broken down into groups of 6 bit data which looks like characters, then
converted back when received, to the original 8 bits. This grouping
introduces extra bits as filler, so to speak, so the file size
increases
as a result of accommodating the lower bit count characters. All this
translates to: the larger the file the larger the increase in
attachment
size and ultimately, the slower the transmission.
This all dates back decades to when about all that was being sent
electronically were characters on teletypes, and the need for more than
just the alphabet and a few other characters was yet unanticipated.
Unfortunately, email was designed along the same concept. The need to
send! binary attachments was an afterthought, which explains the
inefficiencies of the design to do so.
With FTP (File Transmission Protocol), the protocol was designed for
binary data, so there is no similar ballooning of file size upon
transmission.
I'm posting this reply to the IRCA list since this same question has
come up recently and others may be asking it. I trust it is not too far
off topic.
Curt
W. Curt Deegan
Boca Raton, (Southeast) Florida
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