[Top] [All Lists]

Re: [ietf-smtp] Draft for compressing SMTP streams

2016-08-18 12:33:01
+1 to smime@

On Aug 18, 2016, at 7:10 AM, John Levine <johnl(_at_)taugh(_dot_)com> wrote:

Or perhaps 
not want compression at all. SMTP has different problems than IMAP, 
which I think simple compression will not fix: Submit sees a single 
message per connection, plain SMTP sees mostly spam. Why implement 
compression, then?

I think the motivation is people sending around large documents in
formats like Word and Excel.  Pictures and videos aren't very
compressible, but they're base64 encoded so compressing that tends to
get you back to the original size.  (You don't have to tell me that
BINARYMIME and BDAT solve that particular problem better.)

Modern Word and Excel files are in ZIP container formats. Therefore, they are 
already compressed. [Looks like Paul Smith already posted about this.]

I would like to see implementations of SMTP compression, but more important 
than that is binary SMTP (aka BINARYMIME / BDAT), RFC 3030. The difficulty here 
in addition to general SMTP deployment issues, is that storage has to be 
binary-clean, which has effects on POP and IMAP. But that is an easy way to 
save 37%+ on bandwidth.

If the entire payload is base64-encoded and is in standard form (72 characters 
per line, no weird spaces, etc.), then it would be straightforward to convert 
the base64 part (of which only 1 exists) to binary, and then de-convert it back 
for storage.

Servers that support EAI have to support 8-bit clean channels, except for 
control characters and NULL. Therefore they can be seen as part of the same 
(not-small) infrastructure upgrade.

S/MIME supports compression, RFC 3274. It is not widely supported, but I know 
of at least one mail client that supports it. It would be good to support that 
as well, especially since end-to-end encrypted content will not be further 
compressible. OpenPGP already supports compression widely (standard algorithms: 
DEFLATE etc.).


Early on people from Gmail experessed interest, but I haven't heard
from them for a while.


ietf-smtp mailing list

ietf-smtp mailing list

<Prev in Thread] Current Thread [Next in Thread>
  • Re: [ietf-smtp] Draft for compressing SMTP streams, Sean Leonard <=