...before Radix-64 layer and Compression Algorithms?

From: RPK (webmaster_at_hypercypher.zzn.com)
Date: 09/30/03 

Date: 30 Sep 2003 10:41:02 -0700

I have two questions to get cleared:

(1)
I read PGP RFC but it is not clear to me as to what is done when the
final message is prepared with the concatenated packets just before
applying the Radix-64 layer.

For example, if the message looks like:

ProductSignature+TimeStamp+CTB+RSA_encrypted_SessionKey+EncryptedText..
+CRC ......

Now when the final concatenated message is formed, does the Radix-64
layer is applied directly or something else is done before it.

(2)
Why ZIP is only used as a de-facto for compressing messages before
encryption? There are some good compression algorithms like RAR and 7z
which can make the compression even more tighter, however some
speed is also compromised, but if compression makes encryption
stronger then why not opt for tighter compression.
ZIP is sometimes not able to compress well certain type of files.

Relevant Pages

  • Re: AES and Diehard
    ... >you could employ kill file, ... The result of encryption which might eventually develop ... a standard for crypto the 'diversity' of interests is ... compression algorithm could exploit in order to compress. ...
    (sci.crypt)
  • [HPADM] SUMMARY: File Transfer from AS400 to HP-UX with compression and e ncryption?
    ... Also I'd like to know what compression and/or encryption techniques might be ... We're currently doing FTP from AS400 which is taking about 5 hours so they'd ... The gzip site says there is no encryption available for gzip so one would ...
    (HP-UX-Admin)
  • Re: Compression and encryption
    ... I would like to have both encryption (in case the computer gets ... I could tell Windows to compress the files that get written to the ... Windows XP Pro comes with EFS. ... I want both compression and encryption. ...
    (microsoft.public.windowsxp.general)
  • Re: Just a thought...
    ... idea apply bijective arithmetic compression or bijective PPM compression ... like in BICOM before the encryption. ... way even if the correct key was used say for a CBC AES type of encryption ... you could rotate the file using DSC or you could add a secret number ...
    (sci.crypt)
  • Re: Logical Thinking...???
    ... Aside from the fact that it's mighty hard to define "random noise," ... even over a set of common compression methods. ... (to the compressed file + its encryption key ...
    (comp.sys.hp48)