Re: Compression

["Edward H. Currie" <ehcurrie@worldnet.att.net>]

And then of course there's paper tape to be considered ...


-----Original Message-----
From: Herbert R Johnson <hjohnson@pluto.njcc.com>
To: tass@wwa.com <tass@wwa.com>
Date: Wednesday, October 28, 1998 11:54 AM
Subject: Re: Compression


>On Tue, 27 Oct 1998 11:02:43 -0800, Chris Albertson
<chris@topdog.pas1.logicon.com> wrote:
>*>Edward H. Currie wrote:
>*>>
>*>> No one should ever store anything they care about on tape ... if you
doubt
>*>> this ask Ampex ...
>*>
>*>I just had a 4mm tape drive fail a couple weeks ago.  It munched a
>*>tape just like VCRs sometimes do.  If I had been reading my only
>*>copy of a backup tape I'd have lost a few GB of data.
>
>Redundancy is the only way to avoid this kind of failure.
>
>*>The basic fact is "Nothing is secure".
>*>
>*>  Hard disks can be counted on to fail about every five years on
>*>  average.  I personnally have seen examples five years on either
>*>  side of this average.
>
>Me too, but modern drives are pretty good - once you get past the
>first few months (approximately).
>
>*>  CD-R can be destroyed by heat or bright light
>
>Maybe, but I've had one in a plastic case that I obtained a few years ago.
>Seem to be OK. I certainly would not put one in the sun, or leave it
>next to the toaster.
>
>*>  Coatings can come off tape if not stored correctly and defective
>*>  tape drives can destroy tapes
>
>...and CD's too: that aluminum coating on audio CD's for instance.
>
>*>  The most common cause of data loss however, is acidental overwrite.
>*>
>
>If you use alternate media you can minimize this. Two or more backup
>sets of media, use them in rotation.
>
>*>One accepted rule is that data becomes secure if it is writen on
>*>three different media at two different locations.  So one copy on
>
>*>--Chris Albertson
>
>Reasonable advice. Two sets are good, three is better. REminds me I
>need to backup *my* systems.
>
>Herb JOhnson
>
>Herbert R. Johnson              http://pluto.njcc.com/~hjohnson
>hjohnson@pluto.njcc.com         voice 609-771-1503, New Jersey USA
>
>             amateur astronomer and astro-tour guide
>     classic S-100 computers restoration & parts as "Dr. S-100"
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>