CD-QuickShare brings hard drive speed to CD-ROMs
Rex Baldazo
Sharing multiple CD-ROMs on a network can be difficult and costly. Even if you have quad- or six-speed drives, the average seek speed slows noticeably if multiple users access the same drive.
CD-QuickShare, from Stac Electronics, offers a cost-effective alternative. The program creates an image of a CD-ROM, compressing it if possible, on a network hard drive. A small device driver runs on each client workstation, fooling the Microsoft CD Extension (MSCDEX) into thinking that another CD-ROM drive is available.
An administrator creates images of the desired CD-ROMs in a network directory, and each workstation uses a Windows application to "insert" the desired image into
the virtual CD-ROM drive
. From the point of
view of DOS or Windows, the image appears as if it were the original CD-ROM in a physical CD-ROM drive, instead of an image that is coming across the network.
Only the administrator can create new CD-ROM images or remove existing ones. And unfortunately, even though an administrator can create as many images as he or she wants (within the purchased licenses), each workstation has only one virtual CD-ROM drive and thus can use only one image at a time.
The performance of this virtual CD-ROM drive will depend on the speed of your network, but it also depends on the type of network. Running CD-QuickShare on a peer-to-peer network is not as fast or reliable as running it on a server-based network, Stac says. We encountered problems testing it on a Windows for Workgroups network, comprised of a mix of WFW 3.11 and Windows 95 machines.
We never could install CD-QuickShare on two of our Pentium systems that were running Windows 95. The computers wouldn't hang right after loading CDSHARE.EXE, which
happens in the CONFIG.SYS file; instead, they would bring up the Windows 95 GUI, let you log on to the network, and then they would hang. Other Windows 95-equipped Pentium systems ran CD-QuickShare without a problem, so we cannot pinpoint the blame as an incompatibility with the OS or the microprocessor.
Our biggest complaint: We couldn't resume the creation of a CD-ROM image if it was interrupted. On occasion, in the midst of compressing a large CD-ROM, there would be a hiccup in the network, from which CD-QuickShare could not recover. It would abort the session, and we had to start again.
An interesting application of CD-QuickShare is in stand-alone mode, when the CD-ROM images are stored on a local hard drive instead of a network drive. This proved useful for portable computers. With a sufficiently large hard drive, you could store a favorite CD-ROM on your laptop, without having to get a portable CD-ROM drive or an expensive laptop with a built-in CD-ROM drive.
In this mode, Stac expects
that the performance of the virtual CD-ROM drive will approach or surpass the performance of a six-speed drive. In our subjective test using a popular multimedia title, we indeed found performance of the CD-QuickShare drive equal to or faster than that of a Plextor 6-Plex drive.
Home Users Need Not Apply
When creating an image, the administrator must specify how many licenses were purchased for the CD-ROM. CD-QuickShare enforces concurrent use to that number of licenses. There is no report-generation capability, but the administrator can view in real time which users are accessing any of the stored images.
CD-QuickShare is clearly aimed at corporate customers. The cost is $500 for a five-user/five-CD license. On balance, we think it is worth the money. Creating a CD-ROM image can be a hassle, but it's a great solution for Windows workstations. It's a utility that fills a need rather than creating one.
PRODUCT INFO
RMATION
CD-QuickShare.................$500
(five-user/five-CD license)
Stac Electronics
San Diego, CA
(619) 794-4300
fax: (619) 794-4570
http://www.stac.com
screen_link (104 Kbytes)
From your workstation, you insert CD-ROM images in a virtual drive.
Rex Baldazo is a BYTE technical editor. You can contact him on the Internet or BIX at
rbaldazo@bix.com
.
Virtual CDs on the LAN
