Re: [ietf-smtp] Stray <LF> in the middle of messages

Dave Crocker <dhc@dcrocker.net> Wed, 10 June 2020 13:32 UTC

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From: Dave Crocker <dhc@dcrocker.net>
Organization: Brandenburg InternetWorking
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Subject: Re: [ietf-smtp] Stray <LF> in the middle of messages
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On 6/8/2020 7:03 AM, Hector Santos wrote:
> The Internet Mail format officially starting with RFC 822 selected the 
> DOS/Windows format <CR><LF> format.
> 
> Why?


Any interesting computer network seeks interoperability among 
heterogeneous systems.  All sorts of differences need to be dealt with, 
including differences in the end-of-line construct.

The simplest and most scalable way to accomodate such differences is to 
define a /single/ standard and require each system to between their 
local convention and the network's canonical convention.

This approach was as the core or the early Arpanet protocols, including 
FTP as already noted in this thread.  That's from the early 1970s 
timeframe.

RFC 822's predecessor, RFC 733, was 1977.  SMTP was 1982.  They merely 
continued the convention.

Telnet and FTP chose CRLF as the end of line construct.


d/
-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net