ietf-smime
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RE: Compressed data type for S/MIME

1999-07-29 01:43:41
All,

I've been watching this thread with interest and I'd like to raise a few 
observations/questions/issues.  I'd like to make the point first though that 
what follows is not intended to contradict or counter any of the messages that 
proceed this one - I'd just like to widen the debate a little and firm up my 
understanding of the relative merits of performing compression or not.

1. Are we really concerned with saving network bandwidth these days?  If we are 
then clearly compression is essential.  If we're not, why are we discussing it 
at all?

2. If we need compression, how does the algorithm complexity of zlib 
compression algorithm compare with 3DES encryption?  What's its average 
compression rate?

e.g. How does the time to process the data compare in the following:

        a. Encrypt 10Mb of plaintext with 3DES
        b. Compress 10Mb to (say) 5Mb using zlib and then encrypt using 3DES.

3. If b. takes longer than a. and we're not that concerned with network 
bandwidth why bother compressing?  

I think my bottom line questions here are: how important is processing speed 
compared to network bandwidth? and how much time does this aspect of the 
processing take compared with all those cert/crl processes going on in S/MIME 
and/or CMS?

Regards,

Darren

------------------------------------------------------------------------
Darren Harter B.Sc (Hons) CEng MBCS
Application Development Group, UK
Entegrity Solutions Corp.
Tel: +44 1452 371383
Fax: +44 1452 371384
Cell: +44 7801 812850
Email: mailto:darren(_dot_)harter(_at_)entegrity(_dot_)com
http://www.entegrity.com
http://www.entegrity.co.uk