Ok, explain to me...I took a 220MB system file and compressed it down to 28MB.

Obviously this is lossless as I can recover individual files from 
within it that are things like extensions, fonts, etc.

I admit, JPEG, MPEG, etc. are lossful, but modems have been doing 
v.42bis compression which is 4:1 on the fly for a long time now. 
Granted, the speed is only 53k at best (although some faster network 
equipment also uses a subset of v.42bis), so the time frame from 
receiving to sending would be larger that you would get with 
receiving to sending to local device like a tape drive.

I'm wondering if it would be possible for Retrospect to do some 
software compression that may be slower, but would allow greater 
inline compression.  I would guess that the software compression 
built into Retrospect is the same algorythem that hardware 
compression drives use.   By getting with a company like Alladin 
Systems, it would seem like they could improve on that technology.

If Dantz did something like this, obviously having a choice of 
Hardware compression or software compression would still be there, 
but adding to the software compression may be 3 levels.  Normal, 
Better (slower), Best (slowest).

The speed of the compression would depend heavily on the speed of the 
CPU doing the backups.  So if I had my Dual 1Ghz Processor Alpha box 
running NT doing backups, the best compression would be barely 
noticeable performance hit.

I do think that if Dantz should at least talk to someone at Alladin about it.


>One (compound) word: Lossless
>The compression methods that you are lusting after introduce errors
>(artifacts) into the resulting decompressed data. This may be acceptable
>for sound, photos and video but to totally unacceptable for storage of
>system files, programs and most other data.

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