• Removable Media Devices. These are any of the several popular high-capacity
disks, cartridges and tapes that are used in form-specific read/write drives to
record and play-back data. Often some form of compression is used to store
greateramounts of data on each piece of media.
• NetworkAttach Hard Disk Storage (NAS). NAS servers connect directly to the
network and perform the single function of providing additional on-line storage
for cross-platformfile-sharing.
• StorageArea Network (SAN). A storage area network is a scalable network of
servers and storage devices that are typically connected using Fibre Channel hubs
and switches. In full duplex mode up to 200MB of data can be transferred per
second in blocks as large as 128MB making it the highest speed option available.*
• Jukeboxes.A jukebox provides automated, unattended access to data that has been
backed-up onto CDs and/or DVDs. The discs may be stored in groups within
magazines,or may be held in a main carousel.
• Hierarchal Storage Management.Hierarchal StorageManagementis a process that
is implemented throughsoftware according to the data managementpractices
established by the system administrator. These practices specify how certain types
of data are to be handled. For example, certain kinds of financial data might be
backed-up every fifteen minutes, while aged data that had not been used in six
months might be consigned to off-line storage.
• Internet Back-up Services. Certain Internet Service Providers (ISPs) provide
automatic on-line data storageusing an Internet connection. Software provided
by the ISP is maintained on a network device or PC, and is programmedby the
user for prescribed back-up times for any or all data. This option is especially
useful for workers who are out of the physical environment,either travelling or
working from home, since they can access the stored data throughthe Internet.
• Electronic Vaulting. This method moves data directly to a remotesite, usually
through a dedicated network. It is usually expensive, but provides a good level of
security for data-reliant businesses such as financial institutions and stock
brokerages.
• Remote Mirroring. This method is reservedfor those environmentsthat have a
zero tolerance for data faults. All data is mirrored to a remotesite overa
dedicated high-speed network.
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*The FibreChannelprotocol involves the packagingof data before it is sent, and its unpackaging
when it is received. In the case of largefiles, such as full-page, 300 dpi, 24-bit RGB files, this
overhead is inconsequential in comparison to the overall size of the files. However,when many
small files are transferred, the cumulative packagingtime can negativelyaffect performance.
utilized whenever it is required. There are many procedures used to ensure that the back-
up process is conducted on a schedule consistent with the amount and value of the data
generated, and the special needs of the enterprise. Good practices may include such things
as alternating the media and the drive used for back-up, making two or moreback-ups for
each back-up session, or using two distinct and differentmethods (such as different back-
up/restore applications) for each scheduled back-up.
data that has been backed-up foroperationalpurposes. This is routine housekeeping, and
consists of all mission-critical and work-in-progressdata. This data may be needed for
restoring lost or damaged files, or for re-generatingfiles that were deleted accidentally.
Archival Retentionis a purpose that, while practical and essential, may also be mandated by
legal, tax, regulatory, or governmentrequirements. This purpose is generally considered
long-term,and does not necessarily include the same type of data that would needed for
operational or recoverypurposes. The final major reason for backing-up data is fordisaster
recovery,wherein significant data resources have been lost due to some catastrophic event,
such as a destructive virus or a hard drive failure. Disaster recoveryback-ups should be
maintained off-site so that they do not succumb to any local danger,and they should be
duplicated beforebeing used to restorea system, with the original media remaining off-
site.
fail for several reasons. Among the most common is that the back-up media is no good…it
was never tested, and back-up software did not detect a problem. There may have been
networkfaults, caused by a bad cable, or connection, which went undetected. Another
commonerror is attempting to back-up files that are in use, such as open databases, or files
that are in the process of being copied by system users. Even when everything goes right,
and the back-up copy is perfect, and it has been stored off-site, it can get lost in transit, or
after it has been delivered.
fail over time. Each type of media has a projected life span, from approximately ten years
for magnetic media, to several decades for certain types of CD-ROM media. Even if the
media survives the passage of time, theremust be a way of reading it when the time comes.
The technical obsolescence of media readers poses an equal or greater obstacle.
Digital publishing work environments are typified
by a voracious appetite for data. This is due to the enormous digital files that are produced
as the componentelements of projects, such as high-resolution digital photos and video;
and the completed projects, which may be saved in the form of application files, PDFs,
digital movies, multimedia projects, or as RIPed data.
sophisticated still, motion, and interactive products. These products range from brochures
and books,to Websites and interactive presentations. Source files, which may be acquired
fromthe customer,created in-house, purchased from stock houses, or sub-contracted to
outside designers, are generally numerous, and are likely to undergovarious modifications
until they are approved.
hard drive. This is the fastest and most convenient way to access files. Unfortunately, over
time, files, which are no longer a part of in-production work, remain, and the space on local
disk resources fills up. Only throughpracticed discipline, or desperation, will a user
archive completed work to some form of removable storage to safeguard it, and to free up
local disk space.
suggests that there will be a variety of ways in which a digital workflow will be
implemented. A key component of any workflow,however, will be the manner by which
files are saved, and the process by which they are made available to those who need them.
size of the files that are routinely transferred. First, the routine use of large file sizes can be
avoided through the use of OPI (Open Prepress Interface), which allows for the use of
reduced-size proxies in place of high resolution originals.* The low resolution versions are
used for various image manipulation operations, and are incorporated in page layout
applications. The high resolution versions are substituted at output time. Second, various
image compression schemes, such as JPEG, Iterated Systems’ Sting,** and Altamira
Genuine Fractals,*** can be used to reduce the physical size of files without significantly
affecting their quality.
__________
*The OPI standard was published byAldus Corporation in September,1993.
**Iterated Systems, Inc., 3525 Piedmont Rd., Seven Piedmont Center,Suite 600, Atlanta, GA30305, http://
www.iterated.com/.
*** Altamira Group, Inc., 1827 West VerdugoAve.Suite C, Burbank,CA91506, 425-391-0110, http://
www.altamira-group.com.
need no longer be maintained on-line, and may be moved to near-line storage. By burning
final versions of digital assets onto CDs, and serving them via a network-accessible media
jukebox,the following advantages are achieved:
• Every user with a network connection can access the digital assets.
• The digital assets are saved in an immutable form that ensures their integrity.
• Digital Asset Management (DAM) software can be used to catalog the files, and
make them easily accessible through a Web browseror some sort of textual and/
or visual search system.
• The discs are held securely inside a sealed enclosure which protects them from
environmental hazards, and provides the assurance that they are not scattered
throughout the work environment. The media jukebox can be locked in a server
closet or otherwise maintained in a secure place to ensure that they are not
tampered with, or removed.
• Data access can be tracked to determine which data is no longer needed in near-
line form. Such dormant data can be stored off-line.
According to Wolfgang Schlichting, Research Manager of
RemovableStorage for the International Data Corporation, “The CD-R media market
continues to grow exponentially.”* This is understandable fromtwo perspectives. First,
froman economic standpoint, the cost of the media is inexpensive, and CD-R drives are so
reasonably priced that they are often a standard component of an off-the-shelf PC. Second,
froma practical standpoint, the CD format is right-sized for holding most of the elements
that are a standard part of digital publishing workflows.**In addition, there is a smooth
transition to DVD, with considerably greaterstorage capacity, since most CD discs can be
read by DVD readers.
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