LLTI Archives

July 2003, Week 2

LLTI@LISTSERV.DARTMOUTH.EDU

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
LLTI-Editor <[log in to unmask]>
Reply To:
Language Learning and Technology International Information Forum <[log in to unmask]>
Date:
Wed, 9 Jul 2003 11:02:57 EDT
Content-Type:
text/plain
Parts/Attachments:
text/plain (78 lines)
--- Forwarded Message from Jack Burston <[log in to unmask]> ---

>Date: Mon, 07 Jul 2003 11:04:31 -0400
>From: Jack Burston <[log in to unmask]>
>Subject: Re: #7188 Using Disk Images of Language CD ROMS in Lab
>In-reply-to: <[log in to unmask]>
>To: Language Learning and Technology International Information Forum    <[log in to unmask]>
>User-Agent: Microsoft-Entourage/10.1.0.2006

------------------
Dear Joseph,

Centralizing you CD resources to a server is a great way to avoid the
hassles of keeping CDs in local drives (and distributing them to students
for this purpose).  I looked into this rather extensively last year and can
report that, while it can be done, it requires considerably more than
redirecting the path to your CDs.  Dumping the CD to a hard disk is easy
enough, but programs that require the CD to remain in the drive typically
make internal calls to resources which are located in fixed locations on the
CD and these can't simply be rerouted through the OS.

There are basically three solutions to the problem:
1) CD/DVD Disk changer
2) CD/DVD Disk jukebox
3) Virtual CD/DVD jukebox

The following URL gives a good description of these options:
http://www.kintronics.com/jukebox.html


Basically, a disk changer contains a single CD/DVD reader plus a carrousel
mechanism that rotates disks (usually no more than 5) into place.  This is
the cheapest solution, but also the slowest and restricted to a single user
at a time.  

A disk jukebox contains multiple CD/DVD readers and can serve as many
simultaneous users as there are disk drives.  It is also possible to use
disk changers in a jukebox, for example storing 35 disks in 7 changers.
While a jukebox can serve multiple simultaneous users, no user can access
the same CD at the same time unless multiple copies are stored.

The most versatile solution to CD/DVD storage and distribution is the
virtual jukebox.  In essence, this is a dedicated multimedia server upon
which CD/DVD content is stored in large, fast hard disks. The trick here is
special software that in effect tricks the computer into thinking that a
hard disk folder containing the CD/DVD contents is actually a CD drive.
Because they are hard disk based, virtual jukeboxes can serve any
combination of the same or different CD/DVD disks to as many users as
network bandwidth will allow. The amount of bandwidth needed will, above
all, depend on the quantity and quality of video resources needing to be
distributed. In my trials last year with a top end PrimeArray server (see
URL below), I was able to successfully serve up full-screen MPEG video to 32
computers over a IGB backbone with a switched 100 BaseT connection to each
station. Incidentally, with regard to DVDs, it has to be kept in mind that
(aside from copyright restrictions) commercial DVDs will normally scramble
any attempt to copy them to a hard disk.  Lastly, as might be expected, the
versatility of a virtual jukebox come at a price: $5000-$10,000 depending on
CPU and the size and speed of hard disks.

Aside from Kintronics (indicated above), there are two other producers of
virtual jukeboxes of which I am aware:
PrimeArray http://www.primearray.com/).  Be advised though that a Virtual
Jukebox http://www.cdcomputer.com/Virtual%20Jukebox.htm

I trust you find the above of some use.  Jack

-- 
Jack Burston, Ph.D.
Director 
Foreign Language Technology Center
College of Liberal Arts
Rochester Institute of Technology
92 Lomb Memorial Drive
Rochester, NY 14623-5604

Phone: (585) 475-3156
Fax: (585) 475-7120

ATOM RSS1 RSS2