Peripheral Sharing Technology

Beginning with these four general business uses, one should undertake a more thorough analysis of peripheral sharing needs to assist in selecting from the currently available peripheral sharing technology.

These technical requirements can be compared to the non-LAN PC connectivity technology analysis grid for initial possible technology solutions. The technology analysis grid maps peripheral sharing functionality, on the vertical axis, against available technology alternatives on the horizontal axis. Intersections indicate whether a given feature or function is standard or occasionally included in a given device. For example, if the answer to question 12 regarding the need to transfer files and e-mail was affirmative, then referring to the technology analysis grid, only data switches and data PBXs would need to be explored further. The purpose of the technology analysis grid is not to provide definite and final answers but rather to guide product research in a time efficient manner. Each technology alternative listed in the grid is described briefly in the following section.

Printer/Peripheral Sharing Devices

Printer/peripheral sharing devices are often ignored as potential connectivity solutions by uninformed users and aggressive sales people who see LANs as the sole answer to PC connectivity requirements. Cost per connected PC can be as slow as $5 for peripheral sharing devices and as high as $1000 for a sophisticated LAN. Additional costs, such as the need to hire technically oriented personnel to manage LANs, add to overall impact of PC connectivity decision making.

The business motivation that usually brings one to non-LAN PC connectivity is the recognition of the large expense involved in equipping individual PC users with their own dedicated printers. Resource sharing is an obvious solution as users need access to a printer, but not necessarily their own individual printer.

The key challenge of PC connectivity analysis is to grant this access to shared printers while maximizing the productivity of PC-based workers. The trick is to find the best connectivity solution for a given situation in terms of both delivered functionality and cost. Incorrect analysis of the situation may yield unsatisfactory results. Potential non-LAN PC connectivity solutions range from manual switches costing as little as $10 to printer sharing systems costing several hundred dollars. Delivered functionality must always be compared with that delivered by LANs, which can cost anywhere from $100 to $1500 per connected PC.

The specific business activities involved with peripheral sharing are relatively straightforward:

1. Users may wish to share one or more printers among numerous PCs
2. Users may wish to share one or more modems among numerous PCs. This is known as accessing a modern pool.
3. Users may also wish to send e-mail to transfer files to another.
4. Users may wish to occasionally log onto a minicomputer or mainframe. Given the occasional nature of this use, it is important to minimize the number of minicomputer or mainframe ports dedicated to this purpose.

File Transfer Software Applications

File transfer software is popular among information systems professionals responsible for maintenance and troubleshooting of personal computers as well as among auditors and other field-service personnel. When PCs are not connected to LANs updating software or diagnosing problems can be very time consuming. The software’s script language and transfer automation capabilities allow a PC support person to load a software upgrade on a portable PC equipped with file transfer software and move from one PC to another to update all necessary files with a single key stroke.

In some cases, portable or notebook PCs may have no diskette drive at all, or the drive’s size or density may be incompatible with another PC with which must transfer data files. File transfer software is an ideal solution to this problem, as the transfer of data actually takes place via the PCs serial or parallel ports. For ease of use and installation, some file transfer software packages also include the necessary cables to physically link PCs. Software such as Mac-in-DOS and MacLink Plus/PC. Connect provide conversation between Macintosh and DOS or windows file formats in addition to traditional file transfer capabilities.

Thanks to a piece of software known as a device driver, the slave PCs disk drives, and the files contained therein, appear on the master PC as local or virtual drives. They are called virtual drives because they appear to be attached locally although they are not actually contained in the masters PC. A device driver tells the operating system how to control peripheral devices such as disk drives, printers, and network interface cards. Its name and location are added as a line in a file called CONFIG.SYS. This system configuration file is read and executed when DOS-based PC is first powered up or booted. The device drivers are thus loaded into memory, “fooling” the local (master) Pc into thinking that the remote (slave) PCs disk drives is directly attached to it and locally accessible.

It should be noted that file transfer is distinct from file sharing. File transfer sends a copy of a file from one device to another, whereas with file sharing two users have access to a file simultaneously. File sharing as a business requirement falls into the realm of Local Area Networking and exceeds the capabilities of file transfer software or peripheral sharing devices.
As you review the functionality and possible business applications of file transfer software, keep in mind its very affordable price: generally around $100 to $200. Although it can’t replace a full function LAN, it can be a real time saver and, as the saying goes, time is money.