August 1995

Creating a LAN with Windows NT networking products: basics for schools

by Edward J. Branley

School and district computer networking is, without a doubt, one of the most exciting trends in educational computing. At the same time, it can be confusing and difficult to explain. In a world where far too many classrooms stumble along with isolated computers that are years out of date, the language and capabilities of networking can seem like a foreign tongue. In this article, Edward Branley explains some of the basic terminology of networking and examines a range of products worth considering for your school district.

-The Editors

The language and technology of local area networks (LANs) often seems incredibly complicated and obscure. Somehow we don't expect simplicity; the theory seems to be that if it isn't complicated, it can't help. But schools don't need more complications. Schools and teachers need the inherent ease of use of computers and networks running an easy-to-understand graphical user interface (GUI). For the seasoned LAN manager such an interface may make a product seem too simplistic, but such impressions are deceptive. Microsoft's combination of Windows for Workgroups, Windows NT Workstation, and Windows NT Server offers school technology coordinators a range of potential solutions that can be more cost-effective and more readily understood than any other LAN software environment. In this article, we'll examine the basics of how a coherent LAN strategy can enable your district to transform a group of isolated, standalone computers into a system of building-level networks or even district-wide networks attached to the Internet.

Typical network designs

LANs are usually structured in one of two configurations: peer-to-peer or client/server. Peer-to-peer networks are those in which all computers on the network are equal in "stature." In the world of education, the most common type of peer-to-peer LAN is the school-level workgroup that allows users to share files among PCs. There's no need for a centralized file server, so the only step required to create a peer-to-peer network is tying the PCs together. However, the school may require the workgroup to have some low-level security as well as other features, such as the ability to share printers.

In a client/server network design, all computers are not created equal. There's a distinct hierarchy in this type of network, in which the user system (the client) attaches to and implements services on a central system (the server). On a client/server LAN, the most common service is file sharing, which is why the main PC on this type of LAN is usually referred to as a file server. If you want to share a file with another user on a client/server system, you can't just copy the file to the other user's hard drive; you copy it to a directory on the file server and then the other user copies it from that location to his or her hard drive. The same goes for printing: If you want to use a shared printer, you route your print output through the file server.

Many networks are hybrids of peer-to-peer and client/server networks. Some districts like the idea that centralized data is secure and safely backed up, but they still want to offer their users the convenience of easy access to each other's workstations. The Internet is an example of another hybrid system. Internet hosts connect with one another on a peer-to-peer basis, even if one host is a PC running Windows NT and the other is an IBM 3090 mainframe. That same NT workstation may attach to another host in a client mode to retrieve files, USENET news, and other items.

Basic networking vocabulary

Certain basics apply to any network configuration. No matter which design you choose, the first thing everyone needs to understand is the architecture of the LAN. Microsoft products enable peer-to-peer and client/server networking on both Ethernet and Token-Ring networks, using a wide range of wiring configurations appropriate to school systems.

Network Driver Interface Standard

All computers must have a hardware interface to the LAN-usually an add-on card for a PC. Microsoft networking supports the Network Driver Interface Standard (NDIS), which gives schools a number of options when choosing a Network Interface Card (NIC). NDIS is attractive to hardware manufacturers because they no longer have to create specific drivers for Microsoft, Novell, TCP/IP, and so forth. All they have to do is develop an NDIS driver, and it's up to the LAN software to pick up that driver and make it talk to its system.

Network protocols

The NDIS driver links the hardware to a network protocol. Windows networking supports four different protocols: NetBEUI, TCP/IP, NWLink, and DLC. One or more of these protocols is bound to the NIC, which completes the process of linking that PC to the LAN. As Figure A shows, the Network Drivers dialog box in Windows for Workgroups 3.11 indicates which of these protocols are bound to the NIC.

NetBEUI

NetBEUI stands for NetBIOS (Network Basic Input/Output System) Extended User Interface. IBM introduced NetBEUI to the PC universe in 1985. At its best on LANs in the 20-to-200-PC range, NetBEUI is the primary protocol Microsoft implements for its networking solutions. NetBEUI is a single-segment protocol, which means you can't route NetBEUI traffic from one segment of a LAN to another.

NetBEUI has received a bit of a bad name over the years, mainly because the LAN operating systems that have used it in the past haven't sold well. Many people believe that because NetWare, the top-selling network operating system, uses IPX/SPX (Internetwork Packet eXchange/Sequential Packet eXchange), NetBEUI is inherently inferior. This isn't the case, and as Windows-based networking grows in popularity, this attitude will change.

TCP/IP

Transmission Control Protocol/Internet Protocol (TCP/IP) is the backbone of the Internet. TCP/IP is the result of several 1970s government research programs that were developing techniques to link computers at various government and academic sites. As those links expanded, more and more sites adopted TCP/IP. Because the government developed TCP/IP, it isn't proprietary, making this protocol attractive to a number of hardware and software manufacturers. TCP/IP has become the de facto networking standard in the UNIX world and is making serious inroads into the PC and mainframe worlds. It is a sound choice for schools.

Windows networking supports TCP/IP for two main reasons. First, the demand for connectivity to the Internet is growing exponentially as users discover Internet features such as the World Wide Web. The Web is easiest to understand with a graphical client software package such as Mosaic, giving Windows users a way to get onto the Infobahn. Second, there's a need to route network traffic between physical LAN segments. Technology coordinators who need to set up links between buildings, wide-area connections via modems, or connectivity to non-Windows hosts can bind TCP/IP (in addition to NetBEUI) to the NICs in their workstations, as shown in Figure B.

NWLink

It would be foolish to ignore the large number of LANs currently using various versions of Novell's NetWare. NWLink bound to an NIC in a Windows workstation enables the user to access data not only on other Windows workstations and servers but also on NetWare file servers via the IPX/SPX protocol.

DLC

Windows NT and Windows NT Server use the Data-Link Control (DLC) protocol to send information to printers that are network-ready and that don't need to be attached to a PC's serial or parallel port to function (for example, the HP LaserJet IIIsi).

Which Windows version is right for your district?

There are three versions of Windows in the Windows networking family: Windows for Workgroups (WFWG), Windows NT Workstation (NT), and Windows NT Server (NT Server). This proliferation might seem confusing, but there's a method in the Microsoft madness, because each one of these products meets a specific need.

Windows for Workgroups

Windows for Workgroups is the current "entry-level" networking version of Windows. It's also the fastest version of Windows currently available. Users on Windows for Workgroups workstations can do peer-to-peer networking with other WFWG and NT systems and can log onto an NT Server and use its resources. The default networking protocol for WFWG systems is NetBEUI, but you can bind both TCP/IP and IPX/SPX to the workstation's NIC, in addition to or in place of NetBEUI.

Windows NT Workstation

Windows NT Workstation is the next level of workstation software. NT gives users the ability to run more sophisticated 32-bit applications and increases their networking capability. Whereas WFWG is the next logical extension of traditional Windows/PC use, NT brings the PC closer to the level of the UNIX workstation-lots of local power, solid multitasking, and extensive security and networking functions. Both NT and WFWG users are able to access NT workstations on a peer-to-peer basis. A suite of third-party utilities exists that gives NT a number of the Internet capabilities previously available only on a UNIX workstation. This expanded functionality is a significant factor for schools that intend to make the most of their Internet connections. One such utility is shown in Figure C.

An NT workstation is also an excellent platform for database work. Several of the major players in the client/server database arena have brought their products to the NT environment. This is welcome news. Now, an NT workstation can access files on a NetWare server as well as databases on an NT workstation functioning as a database server. This means more flexibility throughout the network.

Windows NT Server

NT Server is to Windows networking what a NetWare file server is to a Novell-based system: a full-functioned, centralized, secured networking environment easily capable of managing an entire district. It's also a lot more. NT Server contains the Remote Access Server, which enables WFWG and NT workstations to access the server via dial-up connections (using NetBEUI and TCP/IP). NT Server has all the features of the Workstation version of NT, so it also makes a solid platform for client/server databases as well as other server functions.

One of the main features Microsoft added to NT Server that it didn't include in NT Workstation is increased fault-tolerance capabilities. This feature includes extensive support for Redundant Arrays of Independent Disks (RAID). RAID subsystems are easy to control in the NT environment, allowing the technology coordinator to monitor performance, step in when there's a problem, and quickly correct it. This degree of protection is a valuable feature in widely scattered districts. As Figure D shows, additional features of NT Server include full control over domain naming and management.

The bottom line

In this article we've reviewed some of the basic terminology of LANs and the capabilities of Microsoft networking products. As we've shown in this article, LANs do not have to be arcane to be effective. A graphical user interface and a clear connection to already familiar desktop applications can go a long way toward making a LAN viable and effective within a school or district.

Windows networking products support this comfort and productivity by drawing on users' PC-based experience. Windows networking tools are growing in popularity, and aggressive pricing by Microsoft is helping to make them even more attractive to schools. As these products grow, it is important to know how they might fit into your school district's overall computer networking plan.

Edward J. Branley is an independent consultant, freelance writer, and Microsoft Certified Professional based in New Orleans. He is also SysOp of Minas Tirith BBS, which is the home of the New Orleans Internet Mailing List. You can reach him at Seashell Software by phone at (504) 221-0838, by e-mail at elendil@yatcom.com or on CompuServe at 71237,2227.