Talk:Magnetic-tape data storage

"Random access"

"...tape is a sequential access medium while disk is a random access medium..."

Please don't call disk random access. It may have a much lower seek time than tape, but it is still very much a sequential storage format. —Preceding unsigned comment added by 81.105.12.50 (talk) 20:42, 4 April 2010 (UTC)[reply]

I would suggest the use of "Direct Access" over "Random Access".

Also, I think it is important to discuss the concept of "soft" formatted sequential versus "hard" formatted sequential access in this section. In soft formatted systems, over-writing an earlier block on the medium destroys all later blocks, or at least renders them unavailable. Hard formatted media, such as most (all?) disk drives and only a very few types of tapes, can be accessed sequentially and non-sequentially without disrupting access to earlier or later blocks on the medium. —Preceding unsigned comment added by 157.127.155.214 (talk) 00:38, 21 May 2010 (UTC)[reply]

Sequential access

Hi "K", I agree that sequential access is an important subject to cover for this topic. I moved the previous text to a subsection of 'Technical Details (and edited it) because the file system stuff is a little more technical than an average reader might be interested in. Let's put a general sentence or two in the opening section and put the more specific file layout details in the technical section. -- Austin Murphy 21:05, 30 March 2007 (UTC)[reply]

Gosh, I tought you've removed it completely. It slipped my attention that you've just moved the text, sorry. --Kubanczyk 12:50, 3 April 2007 (UTC)[reply]

Redirected Data tape cartridge

A merge of content from the Data tape cartridge article was suggested, and I believe that it is a good idea - there really isn't anything in that article that is not already (or could not already be) covered in this one. However, I had trouble figuring out where, and if, the data from that article should be placed in this one. Here is the content from Data tape cartridge:

Information storage in year 1949 meant books, filing cabinets or punch cards. Tape cartridge was the stuff of science fiction. The limitations of punch cards were becoming obvious. The data storage problem as acres of filing cabinets filled with punched cards containing Social Security data echoed that a more compact means of storing data needed to be developed. The emergence of magnetic tape in 1952 by IBM was a big leap in terms of data storage. Throughout the 1950s and 60s, magnetic tape units offered successive improvement in data storage.

IBM produced the first automated data tape in 1974 bringing with it great innovations that in turn led the technology to a newer heights of data storage. One breakthrough was the introduction of 5.5 inch square data tape cartridge storing up to 200 MB data and executing at the rate of 3 MB/s requiring less than half of the floor space of an equivalent installation of its predecessor technology – magnetic tape units - from just a decade earlier.

Data tape cartridge was widely used in the early 70s and 80s for Data storage (a format of storing and backing up computer data on a storage device). The drawback is that tape drive must spend a considerable amount of time winding tape between reels to read any one particular piece of data. As a result, tape cartridges have very slow average seek times. However, it replaced many of the demerits of its predecessor technology (magnetic tape) with its high speed, non- bulkiness, low cost and stability. Now-a-days, we use the same technology of data tape cartridge in terms of 4 mm/8 mm data tapes, mini DV, VHS video etc.

References:

1. Storing the information age: 50 years of tape storage innovation: http://www-8.ibm.com/nz/media/downloads/IBMarticles/Storing_the_Information_Age.pdf 2. Wikipedia reference: http://en.wikipedia.org 3. Data tape category range by Sony.

I am unfamiliar with this subject. Is there any information contained above that should be placed in the Magnetic tape data storage article? I know that the article I've redirected had major tone issues, but is there anything factual that we should place into this article from it that isn't already present? Thanks for the input. *Vendetta* _{(whois talk edits)} 21:54, 5 April 2007 (UTC)[reply]

Tape Lifetime

It would be good to have some comments (or a reference to, for instance, Digital_permanence) about shelf life of the media, possibly compared with other media (notably hard drives and flash). —The preceding unsigned comment was added by 206.168.13.209 (talk) 14:34, August 22, 2007 (UTC) The manufactures of Enterprise Tape Media warrant their tape for 30 years of self life. The question becomes will there be a drive to read it? The 3480 media began in 1984, and still can be read today.141.202.248.52 (talk) 17:50, 2 November 2010 (UTC)Keith141.202.248.52 (talk) 17:50, 2 November 2010 (UTC)[reply]

format not mentioned

Honeywell VLDS (very large data store) c.1990 stored 5.2 GB on an S-VHS tape. Later spun off as Metrum.

"METRUM, established in 1954, is the former Test Instruments Division of Honeywell (NYSE:HON). In September 1990, this business, under the METRUM corporate name, was part of a corporate spin-off of several divisions of Honeywell into the newly formed Alliant Techsystems Inc. (NYSE:ATK). METRUM was acquired by Group Technologies in December 1992."

--Group Technologies' Metrum Subsidiary Sells Peripheral Products Business To Mountaingate

Expansion of formats

There is only one passing reference to Exabyte, which needs to be expanded. Exabyte did much to kill 9-track (certainly) as a backup medium since a 2GB cartridge could be left unattended instead of having operators changing tapes. DLT effectively killed the Exabyte due to superior performance and capacity.

Seismic acquisition has always been a big user of tape , and 21 track , one inch tape was used in large quantities before GCR recording of 9 track , half inch tape really took over. —Preceding unsigned comment added by 80.169.130.254 (talk) 10:49, 25 August 2010 (UTC)[reply]

Potter Instruments

It is rather odd and sad that Potter Instruments, with its many, many contributions to magnetic tape (and disk)recording technology is all but forgotten. The company folded in the seventies. They held hundreds of patents including 6250 GCR which was done for Burroughs. They were another of the "plug compatable" tape, disk and printer manufacturers during the sixties, early seventies. IBM used (under license) many of those patents. Woodym1 (talk) 00:29, 6 October 2008 (UTC)[reply]

Physical mechanisms

What about the physical mechanisms involved in recording and reading? —Preceding unsigned comment added by 84.120.155.124 (talk) 19:29, 6 February 2010 (UTC)[reply]

Same as for hard disk drive. See also Tape drive. --Kubanczyk (talk) 09:00, 22 February 2010 (UTC)[reply]

Random access to data

The section confuses the notions of random access (it takes the same amount of time to read any block on the device), sequential access (it takes a lot longer to read some blocks than others), device i/o (reads and writes to the physical device with no structure imposed by the operating system), and a filesystem (reads and writes to abstract device; units of storage can be accessed by name).Glrx (talk) 16:01, 27 April 2010 (UTC)[reply]

Viability

I don't know much on the subject, but I think that the "Viability" section should be scrapped and re-written by someone who does. I looked up this article while reading about the fact that the tape market has barely declined in the last 30-odd years. It seems that the people who claim that tape storage is on its way out aren't the people who has a reason to use it. From what I have read, there is no current viable alternative for long-term storage. Disks need power; tapes do not. Disks usually fail within 10 years or so; tapes do not.

Also, I have a feeling that the $37,000 figure is a bit misleading. Whether it is true or not, it doesn't necessarily reflect typical pricing. According to the .pdf file linked at the end, tapes sell for less than $1/GB (according to Brett Roscoe, Dell Senior manager) and that doesn't count compression. Note: the article is dated at 2008 and is sponsored by Dell. —Preceding unsigned comment added by 79.97.108.130 (talk) 10:56, 11 June 2010 (UTC)[reply]

The viability section appears biased, but the underlying issue seems significant. There are characteristics that should come out in the comparisons: cost per TB, volume of a cartridge, access time, transfer rate, areal density, operation costs, reliability, media lifetime, and power consumption. How such large stores are used is also significant. The section must also respect WP:NOR. Glrx (talk) 00:58, 12 August 2010 (UTC)[reply]

With a tape cartridge capacities of 1 TB, data transfer rates of 160 MB per second and a cost of $150 per cartridge that’s $50/TB (assuming 3:1 compression) tape remains a viable data storage device. Cartridge capacities are projected to reach 50 terabytes by 2019 with data rates over 1 gigabyte per second. Media life for both the midrange and enterprise tape is 15 and 30 yrs. MTBF (Mean Time Between Failure) ranges from 250,000 – 400,000 hours at 100 percent duty cycle. While the $37,000 figure may be MSRP the street price would be closer to $15K-22K.141.202.248.52 (talk) 18:27, 2 November 2010 (UTC)Keith141.202.248.52 (talk) 18:27, 2 November 2010 (UTC)[reply]