Article 45221 of comp.sys.amiga.hardware: Path: news.csos.orst.edu!atlantis.CSOS.ORST.EDU!ridgwad From: ridgwad@atlantis.CSOS.ORST.EDU (Dean Ridgway) Newsgroups: comp.sys.amiga.hardware Subject: DC6250 data longevity Followup-To: comp.sys.amiga.hardware Date: 19 Jun 1993 08:59:42 GMT Organization: CS Dept. Oregon State University, Corvallis, Oregon. Lines: 17 Message-ID: <1vukhv$3l4@CSOS.ORST.EDU> NNTP-Posting-Host: atlantis.csos.orst.edu Keywords: DC6250 tape data cartridge Greetings. I have a question about DC6250 data longevity. I have been using a tape streamer for my monthly backups, and now desire to use it for LONG term bulk storage. I know from my old Commodore PET days that even high-quality audio tapes "faded" over the years. I lost a consulting bid once because I could not resurrect data stored on audio tape. If I record data on a virgin DC6250 cartridge and throw it in a (cheap) fire resistant shoebox, realistically, how years later can I expect to reliably extract the data? The data will be stored in 25meg "chunks" with either QuarterBack or BTN/TAR (I haven't decided yet). The data WILL be encrypted. Thank you. Dean Ridgway | FidoNet 1:357/1.103 | InterNet ridgwad@atlantis.csos.orst.edu | CIS 73225,512 | ridgwad@jacobs.csos.orst.edu Article 45251 of comp.sys.amiga.hardware: Path: news.csos.orst.edu!flop.ENGR.ORST.EDU!rutgers!cs.utexas.edu!usc!sdd.hp.com!portal!cup.portal.com!thad From: thad@cup.portal.com (Thad P Floryan) Newsgroups: comp.sys.amiga.hardware Subject: Re: DC6250 data longevity Message-ID: <83696@cup.portal.com> Date: 20 Jun 93 00:43:01 GMT References: <1vukhv$3l4@CSOS.ORST.EDU> Organization: The Portal System (TM) Lines: 41 In article <1vukhv$3l4@CSOS.ORST.EDU> ridgwad@atlantis.CSOS.ORST.EDU (Dean Ridgway) writes: | Greetings. I have a question about DC6250 data longevity. I have been | using a tape streamer for my monthly backups, and now desire to use it for | LONG term bulk storage. I know from my old Commodore PET days that even | high-quality audio tapes "faded" over the years. I lost a consulting bid | once because I could not resurrect data stored on audio tape. | | If I record data on a virgin DC6250 cartridge and throw it in a (cheap) | fire resistant shoebox, realistically, how years later can I expect to | reliably extract the data? As a reference point, I have a bunch of QIC tapes from the mid-1980s which are still readable. For example, "SunOS 3.2 SUNBIN DOMESTIC 68020" which are dated Nov.21,1986 and have languished in my desk drawer are still fine. Your "bad" experiences are with audio tapes on which information is recorded in an analog fashion (varying signal levels, etc.). Contrast this with digital recording in which the 1s and 0s are (essentially) saturated full-on or -off. I have 9-track 2400' 1/2" tape from the mid-1970s which are still readable just fine (on my DEC-20 systems). Thus, given reasonable care (avoid excessive heat, proximity to anything metallic, etc.) I would see no reason why one couldn't expect data to remain "good" for at _least_ 10 years. Given media cost and your concern for longevity, I would _strongly_ advise making at least one (and possibly two) backup(s), and keeping the backup(s) at yet another location (i.e. bank safety deposit vault, wrapped in 2" foam to prevent contacting metal walls of the tray). | The data will be stored in 25meg "chunks" with either QuarterBack or BTN/TAR | (I haven't decided yet). The data WILL be encrypted. Be SURE you have copies of the encryption program! And don't forget the password (or keys). Thad Floryan [ thad@btr.com, thad@cup.portal.com, thad@netcom.com ] From cobra%coyote.UUCP@noao.edu Sat Jun 19 22:49:35 1993 Received: from noao.edu by atlantis.CSOS.ORST.EDU (5.61/1.34) id AA22871; Sat, 19 Jun 93 22:49:30 -0700 Received: from coyote.UUCP by noao.edu via UUCP (4.1/SAG-Noao.G89) id AA07688; Sat, 19 Jun 93 22:46:47 MST; for ridgwad@atlantis.CSOS.ORST.EDU Received: by coyote.datalog.com (/\=-/\ Smail3.1.16.1 #16.23) id ; Sat, 19 Jun 93 21:57 MST To: ridgwad@atlantis.CSOS.ORST.EDU (Dean Ridgway) Subject: Re: DC6250 data longevity Keywords: DC6250 tape data cartridge From: cobra@coyote.datalog.com (Ken Thompson) Message-Id: Date: Sat, 19 Jun 93 21:51:29 MST In-Reply-To: <1vukhv$3l4@CSOS.ORST.EDU> Organization: Datalog Consulting, Tucson, AZ Status: R ridgwad@atlantis.CSOS.ORST.EDU (Dean Ridgway) writes: > Greetings. I have a question about DC6250 data longevity. I have been using > tape streamer for my monthly backups, and now desire to use it for LONG term > bulk storage. I know from my old Commodore PET days that even high-quality > audio tapes "faded" over the years. I lost a consulting bid once because I > could not resurrect data stored on audio tape. > > If I record data on a virgin DC6250 cartridge and throw it in a (cheap) fire > resistant shoebox, realistically, how years later can I expect to reliably > extract the data? > > The data will be stored in 25meg "chunks" with either QuarterBack or BTN/TAR > (I haven't decided yet). The data WILL be encrypted. > > Thank you. > > Dean Ridgway | FidoNet 1:357/1.103 | InterNet ridgwad@atlantis.csos.orst.edu > | CIS 73225,512 | ridgwad@jacobs.csos.orst.edu >From my broadcasting days (long ago...), I can tell you that a tape will last the longest if it's stored vertically in a temperature and humidity controlled environment (25 degrees C +/- 3, relative humidity should be in the 30%-70% range. It's moisture that will kill a tape, rather than humidity, so... I'd guess that a data tape (nope, I don't have one at home...) would probably have the same longevity in that as long as the temperature and humidity is consistant, then you really shouldn't have a problem. A 'cheap' solution to storage in a controlled environment might be to get a safety deposit box at your bank...or stick the tapes in the one you might already have - if memory serves me right, those things stay pretty constant (thermally). The drawback, obviously, would be access to the data - kinda depends how valuable it is to you (seems like it'd be important, considering it's encripted...) Luck to ya - just a feeble thought for ya! :) _____ ______________________ _____ |/ | | cobra@datalog.com | | /\ |\ en |hompson | cobra@jab.tus.az.us | |ucson, /--\rizona ------------------------------------------------------------------ Article 45311 of comp.sys.amiga.hardware: Path: news.csos.orst.edu!flop.ENGR.ORST.EDU!rutgers!gatech!howland.reston.ans.net!spool.mu.edu!uunet!portal!cup.portal.com!FelineGrace From: FelineGrace@cup.portal.com (Dana B Bourgeois) Newsgroups: comp.sys.amiga.hardware Subject: Re: DC6250 data longevity Message-ID: <83781@cup.portal.com> Date: 21 Jun 93 15:17:56 GMT References: <1vukhv$3l4@CSOS.ORST.EDU> <83696@cup.portal.com> Organization: The Portal System (TM) Lines: 10 The Federal government has procedures and specifications that cover this area. Sorry but I don't know the numbers. However, with some detective work you should be able to find an index which will give these reference numbers to you. kThe specs will tell you haw to store which kind kof media to get so many years life. They will be conservative. Alternatively, you could get a WORM drive and store data on it which is good for 30+ years. Dana Bourgeois felinegrace@cup.portal.com From cobra%coyote.UUCP@noao.edu Mon Jun 21 21:55:21 1993 Received: from noao.edu by atlantis.CSOS.ORST.EDU (5.61/1.34) id AA16988; Mon, 21 Jun 93 21:55:16 -0700 Received: from coyote.UUCP by noao.edu via UUCP (4.1/SAG-Noao.G89) id AA09683; Mon, 21 Jun 93 21:52:34 MST; for ridgwad@atlantis.CSOS.ORST.EDU Received: by coyote.datalog.com (/\=-/\ Smail3.1.16.1 #16.23) id ; Mon, 21 Jun 93 21:33 MST To: Dean Ridgway Subject: Re: DC6250 data longevity From: cobra@coyote.datalog.com (Ken Thompson) Message-Id: Date: Mon, 21 Jun 93 21:30:45 MST In-Reply-To: <9306212136.AA12641@atlantis.CSOS.ORST.EDU> Organization: Datalog Consulting, Tucson, AZ Status: R Dean Ridgway writes: > >From my broadcasting days (long ago...), I can tell you that a tape will > >last the longest if it's stored vertically in a temperature and humidity > >controlled environment (25 degrees C +/- 3, relative humidity should be > >in the 30%-70% range. It's moisture that will kill a tape, rather than > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > I didn't even consider humidity, thanks a lot! > > I mainly just wanted to know if data cartridges would hold data for AT LEAST > as long as the original disk would, but environmental extremes is something > I haven't considered. Theoretically, stored under the proper conditions, yeah, it should be there years later. I noticed in the net someone else mentioned the safe deposit box routine unless you have a way to REALLY keep the temperature and humidity at a constant level, that might be your best (and safest...) bet in keeping the tape at a constant thermal and moisture level. Luck to you! _____ ______________________ _____ |/ | | cobra@datalog.com | | /\ |\ en |hompson | cobra@jab.tus.az.us | |ucson, /--\rizona ------------------------------------------------------------------