email - Reasoning behing 76 being the line length limit for MIME sections, as defined by RFC 2045? -

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rfc 2045 defines maxmimum line length encoded data 76 - cannot find explanation why 76. number entirely arbitrary, or there reasoning behind it?

rfc2822 legacy standard of email. in section 2.1.1 of rfc2822, can find reason below: affects mime.

there 2 limits standard places on number of characters in line. each line of characters must no more 998 characters, , should no more 78 characters, excluding crlf.

the 998 character limit due limitations in many implementations send, receive, or store internet message format messages cannot handle more 998 characters on line. receiving implementations handle arbitrarily large number of characters in line robustness sake. however, there many implementations (in compliance transport requirements of [rfc2821]) not accept messages containing more 1000 character including cr , lf per line, important implementations not create such messages.

the more conservative 78 character recommendation accommodate many implementations of user interfaces display these messages may truncate, or disastrously wrap, display of more 78 characters per line, in spite of fact such implementations non-conformant intent of specification (and of [rfc2821] if cause information lost). again, though limitation put on messages, encumbant upon implementations display messages handle arbitrarily large number of characters in line (certainly @ least 998 character limit) sake of robustness.


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