Network Operating Systems

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The world of networking has gone through many phases in the last 40 years. Starting with the connection of so-called "dumb terminals" to mainframe systems, there has always been a desire to access information and share that information among many users. To that end, a number of different software vendors have developed what are called network operating systems-first to simply bring about the sharing users wanted and then to add additional services for both end users and administrators. By the early 1990s, three companies stood out as NOS vendors: Banyan, Novell, and Microsoft. This chapter examines these three companies and their network software offerings.

History of Network Operating Systems
Following the introduction of IBM's personal computer (PC) in 1981, many users were happy to simply use these devices as IBM had intended: as replacements for dumb terminals. However, many users wanted to connect these intelligent machines together. With this in mind, this chapter takes a short look at the development of general NOS systems before discussing the various systems in the NOS world.

Only two short years after IBM's introduction of the PC, Novell came along with its first NetWare product. This was the first truly configurable NOS. At the same time, IBM was busy inventing its early PC networking capabilities. In order to connect its PCs, IBM created NetBIOS (Network Basic Input/Output System), later extending it to be called NetBEUI (NetBIOS Extended User Interface).

Novell Dominates the Market
NetBIOS/NetBEUI enables applications on different computers to communicate within a LAN. IBM's NetBEUI enables PCs to send data to other PCs without requiring more than one return acknowledgment to show that the data has reached its destination. Microsoft obtained permission from IBM to use NetBEUI in its Microsoft products, but neither IBM nor Microsoft was able to parlay the use of NetBEUI into anything even closely resembling NetWare.
Novell was on top of the world in those days. At one point in 1986, it was claimed that Novell controlled nearly 85 percent of the PC network business, and it may have had closer to 95 percent. Everywhere you looked, Novell LANs were chugging away. Microsoft didn't see Novell as a threat; Microsoft was busy trying to establish a graphical interface for PC users.

The two main protocols invented by Novell that enabled NetWare to be so successful are IPX and SPX. IPX stands for Internetwork Packet Exchange. It's a connectionless protocol designed to carry data from one place to another. SPX (Sequenced Packet Exchange) is a connection-oriented complement to IPX (see Chapter 4, "The Network and Transport Layers," for a full discussion of protocols, both connection oriented and connectionless).

IPX/SPX was, and is, a force to be reckoned with. This combination of two protocols is what gave Novell its competitive edge. Microsofts MSNet product, and its successors, LAN Manager and Windows NT Advanced Server, used the NetBEUI protocol as the main protocol. Because NetBEUI is not a routable protocol (IPX/SPX is), the Microsoft networking products languished in small, departmental LANs while Novell moved on to larger and larger installations.

New Players Emerge
It was not until Microsoft came out with Windows for Workgroups (WFWG) that any of Microsoft's corporate strides were considered important to the world of NOS development. In the meantime, Novell continued to improve NetWare's capabilities while capturing the market. Another player emerged in the 1980s as well, Banyan Systems, Inc.; the product it created was called VINES.

The VINES system has always been considered the most enterprise ready of the major LAN systems, but add-ons and configuration changes were very expensive, so Banyan's marketing attempts have become textbook cases in how not to advertise and sell a product.

By 1990, Microsoft had started to realize the importance of PC networks and, more importantly, peer-to-peer networking, where end users decide what to share with whom. NetBEUI was added to the very successful Windows 3 desktop operating system to create Windows for Workgroups. This enabled users with very small network needs, perhaps I to 100 users, to get a network up and running very quickly.

Microsoft Takes Hold
Microsoft began to see the light in the late 1980s. When users began to believe that a graphical user interface was a great idea, Microsoft reacted with the development of Windows 3.0. This was the first practical graphical user interface Microsoft developed. Novell designed its system to enable DOS and Windows users to network their PCs quite easily. You would think this was a marriage made in heaven, but apparently, Microsoft felt as though networking services should be incorporated into its Windows system.
Novell had done what it set out to do. It had created a seamless network interface capable of passing data on large, interconnected PC networks. Also, because Novell client stations ran DOS, Windows, and other operating systems, users of Novell could use applications with which they were already familiar. Novell simply gave them the capability to share files and other resources, such as printers and tape drives.

Microsoft decided to change its strategy at this point. When it became apparent that its networking capabilities were far behind those of Novell and Banyan, Microsoft decided to incorporate networking services within the Windows operating system. With that in mind, Microsoft developed the Windows NT system.

Traditional Services of a NOS
Throughout the development of network operating systems, users have traditionally required three major services in a NOS: file and resource sharing, configurability and usability, and support after sale.

File and Resource Sharing
There has always been demand for file sharing. This was probably the most fundamental requirement users stressed when demanding network services. Following that, there has always been a marked demand for resource sharing-in other words, sharing printers, tape drives, and myriad other expensive resources. These are the two basic tenets for a NOS to be considered usable.

Configurability and Usability
The next area of concern is configurability and usability. Novell NetWare administrators all swear by NetWare, and Windows NT administrators tell you that not until the graphic environment of NT came along was there ever a good NOS. Still others, such as users of VINES or other lesser-known systems, tell you that their NOS is, without a doubt, the best. However, there's no doubt that Windows NT provides the easiest interface by far. That ease, however, comes at a price. Although a graphical user interface (GUI) may seem easier to use, many times it does not provide informative explanations as to why something is not working correctly. Microsoft's interface is wonderful as long as everything is working correctly. However, when something goes wrong, many times the user is presented with a graphic message that says something to the effect of "Kernel Error 3 22;" with an OK button beneath the message. Clicking the button may make the user feel he is accomplishing something, but in reality, he is not. Obviously, the error is not OK, so unless someone can get to the root of the problem, the interface offers no clues. Microsoft's documentation has historically been less than complete, and many times administrators do not know what they're doing when they simply click a certain icon or area on the screen. Organizations are therefore forced to expend a great deal of money to train people to use NT properly.

Novell may not have had a graphical interface in the beginning, but it had something no other NOS vendor had: the best documentation on the market. Those bright red NetWare books were absolutely splendid. Novell continues to provide the best documentation of all NOS vendors, although today it's in an electronic format. Microsoft is getting better, but Novell's documentation continues to make the setup, configuration, and administration of NetWare an easy task. Banyan's interface is easy to use, and it's quite easy to set up a Banyan network. However, the documentation leaves much to be desired. It's not nearly as clear as Novell's, and the first-time user of the product is usually quite perplexed as to how to get the network up and running.

When Windows for Workgroups (WFWG) came along, things got slightly easier. Recall that Windows for Workgroups was preloaded with NetBEUI only, so if you wanted to use WFWG on a LAN, you needed to load an additional protocol into the system. This was done via the graphical interface, and it generally worked well enough. However, there were times when Microsoft's interface was at best cryptic, when providing status of error messages.

Again, Microsoft had missed the boat as far as ease of use was concerned. Not until Windows NT Server did Microsoft finally come up with an easy-to-use interface. As mentioned earlier, this was (and is) a double-edged sword. Furthermore, Microsoft's documentation on early versions of NT was worthless.

Support After Sale
If you wanted to get any kind of useful information, it was necessary to seek it from someone who had learned how to do it on his own. Microsoft's support structure was often described as "disastrous" in those days. Hours on the telephone listening to music were what usually ensued whenever someone called Microsoft. Microsoft was so inundated with calls after the release of Windows 3.0-most of which it could not address in a timely manner-that its reputation was nearly ruined. Microsoft's support structure, a this time, was not adequate for the number of calls it was receiving. Many people became very discouraged with the waiting associated with each call.

Novell, on the other hand, has always provided excellent support and service to its cus~ tomers. It is prompt, usually courteous, and helpful. Banyan is a mixed bag. Sometimes it's excellent; other times, it's not. Configurability, usability, and support are always important to users of NOS software and systems.

Let's continue by looking at the three major vendors and their NOSs in detail.

Banyan Network Svstems
Banyan has tried to assert itself as a leader in enterprise-wide network solutions with i NOS software called VINES. Banyan has always made claims that its networks are transparent to the user. By making all the resources on a distributed network seem as if they're compiled into one seamless network, Banyan claims VINES to be the choice for PC-based network solutions. The following sections review VINES' applications and services.

Services and Applications of VINES
The key to making VINES work over distributed network systems is the Enterprise Network Services (ENS) portion of VINES. ENS includes the following services and applications:

All four services work with each other across an entire wide area network (WAN) or distributed network. The next sections briefly review each of these services.

Directory Services (StreetTalk)
Directory and file services are the real "meat" of any NOS, and Banyan has an excellent package to perform these services. The software that enables VINES to provide acrossthe-board services to all users of the network is called StreetTalk. Banyan developed StreetTalk to standardize file and directory services. This product basically lets you share file and directory resources on a Banyan LAN with other types of file services such as NFS (UNIX), NTFS (Windows NT File System), and the old DOS-style FAT (File Allocation Table) systems. The product works well. StreetTalk automatically integrates newly added network locations into the existing network. This makes it very easy to set up and use.

Another important feature of StreetTalk is that it exists on each VINES server in the network. When one server running StreetTalk fails, the entire network directory/file sharing capabilities do not fail, as you might expect. Each server maintains a part of the "puzzle" and, together, the StreetTalk information on all the servers combines to form the entire picture. When one server fails, the other servers are still able to locate the users and resources they support.

StreetTalk is fully integrated into every other part of VINES. Mail, print, and file services all use StreetTalk in order to locate a user or resource on the network. StreetTalk enables users to log in from anywhere on the VINES network; interfaces look the same whether users are on the road or in the office. When new devices, users, and resources are added to the network, StreetTalk assigns each of them a name. This is how StreetTalk is able to keep track of everything.

An excellent feature of StreetTalk is its capability to keep users "straight" when they move to a new location on the network. Network changes are a fact of everyday life. StreetTalk enables administrators to leave a user's workstation exactly as it is when the user moves to a new location. StreetTalk determines the new location as soon as the user logs in for the first time. This is a real timesaver for network administration personnel.

Finally, the StreetTalk Directory Assistance (STDA) service enables users and administrators to look up items, in much the same way they would view the Yellow Pages. All resources can be listed in alphabetical order using STDA. This makes it very easy to find users, resources, and servers on large VINES networks.

Network Management Services
VINES includes what Banyan calls Network Management Services (NMS). VINES NMS has an easy-to-use interface that provides reliable information to administrators. Items such as user activities, network changes and deletions, security, applications, and performance are all manageable with VINES NMS.

Coupled with this is the VINES Assistant. This service provides useful utilities designed to maximize network performance and the control of resources for administrators. VINES also includes password-control utilities, network-optimization utilities, and many others. It's a menu-driven system that steps you through each operation.

Intelligent Messaging Services
VINES messaging sets itself up automatically and works well with any third-party email program. It's fully integrated with StreetTalk, so users need to be registered in the StreetTalk database on only one server. Users are then free to "wander" around the network, use their email login to receive mail at any workstation, and view address information pertaining to users on the network no matter where they're located. This is made possible due to the fact that user address information is maintained in StreetTalk only. Therefore, users may choose any email client program to use, and it will correctly communicate with VINES messaging services. Further, these messaging services are tied into the NMS system as well, so administrators can monitor all email if need be.

Security Services VINES security services are transparent to users of the network, but they are very effective. VINES security services can secure files, printers, gateways, applications, and all other resources. Control of resources is at the source, so even if a hacker is physically connected to a server, he's not going to gain access to a resource unless he's in the Access Rights List (ARL) for that server. The ARL keeps track of who is authorized to use what on the network. Using the ARL is a very easy way to manage the security of resources on a VINES network.

VINES-Supported Standards
VINES can support a variety of standards and protocols on its communication links as well as on several client operating systems. Here are the major standards supported by VINES: Strengths and Weaknesses of VINES
Banyan does not want you to know that VINES has its roots in UNIX. In fact, UNIX is the underlying operating system that makes VINES operate. UNIX is sometimes frowned upon by supporters of current technology. Although UNIX has been around for a long time, it's still an excellent operating system. However, the age of UNIX tends to scare some people. The real strength of VINES lies in its StreetTalk Directory Service. This hierarchical naming of people and resources for enterprisewide directory services is actually the first of its kind. It's very reliable and configurable. Another strength of VINES is that it supports multiple platforms via ENS: NetWare, UNIX (AIX, SCO, and Solaris), and NT versions, This enables all these other LAN systems to be included in the StreetTalk directory services.

Despite its compelling strengths, the weaknesses of VINES are many. Hardware device support is extremely limited. (Windows NT can detect and set up most hardware devices in seconds.) The fact that VINES is built on an old UNIX platform means that detection is not viable. Furthermore, VINES can support only a limited number of devices. This fact, coupled with the dismal technical support available for VINES, makes it a poor choice for a new network starting up. Banyan does not appear to be committed to continued research and development of the VINES product. Unfortunately, the future does not look good for Banyan VINES.

Novell NetWare
Novell set the standard when it came to the rapid growth of LANs in the world. Banyan, on the other hand, may have beat Novell to the punch in creating directory services. After all, Banyan's StreetTalk was really the first LAN directory service. Novell, however, didn't wait long to play catch-up. In fact, after Novell poised itself to take on networking and LANs, it did so with a mighty force. There were no other corporations around that took networks and LANs as seriously as Novell did in the early 1980s. For that reason, Novell is still the top player in the NOS business. According to International Data Corporation (IDC), in 1996, worldwide shipments of server operating systems totaled 2.4 million units. Of this total, IDC attributed a 41 percent share to Novell. Between 1996 and 2000, IDC has projected Novell's share of the network operating systems market to grow at a compound rate of 8 percent. Recall that Novell was the first NOS to support multiple platforms. It was also the first NOS to support multiple and varying topologies and routes between these differing topologies. The real boost for Novell is that it was the first NOS to support all DOSversion networks. Novell also gave Apple a fair deal-NetWare was the first NOS that could provide TCP/IP services to Apple systems. That was a big plus in the heyday of AppleTalk and other Apple systems. The next section discusses the primary features of NetWare. These features make Novell NetWare the powerhouse that it is.

Features of NetWare
The main reason Novell NetWare servers typically outperform other network servers is that NetWare is, by design, a network operating system. Recall that Banyan has its roots in UNIX. Microsoft NT is also an operating system, but it wasn't designed strictly for network performance and service, as NetWare was. A NetWare server is optimized for network activity. This gives it a great edge over other NOS servers. The following sections review NetWare's main features: - NetWare Loadable Modules (NLMs)
Of these six main features, the NDS offering is what makes Novell a strong competitor of Windows NT. Following Banyan's creation of StreetTalk, Novell fought back with NDS. The next sections discuss NDS as well as the five other features of NetWare.

Novell Directory Services (NDS)
Novell decided to adhere to the CCITT (the International Consulting Committee for Telephone and Telegraph, abbreviated from the French) X.500 standard when setting up its NDS system. In fact, Novell has been fairly good about following open standards when defining its network products. By adhering to the X.500 hierarchical namespace structure, NDS prevents the creation of duplicate objects. Each object must have a distinguished name (DN). For example, if you have an employee named Bill in the sales department, the DN for the user object B ILL in the sales department, which is part of the 2345 organization, would be BILL. SALES. 2345. The username BILL (without SALES.2345) is called an RDN, which stands for relative distinguished name.

In Novell NDS, you must uniquely identify every object in the directory tree. This is accomplished by defining its location in the tree. For that reason, you can use the same RDN in more than one container. In Novell NDS, a container is like a repository of information pertaining to a group or cluster of people that exists on certain servers. For example, you can use the RDN of BILL in both the SALES. 2345 container and the HR. 2345 container. This is a very powerful feature of the NDS system. To further break things down, NDS includes intermediate objects, which Novell calls container objects. These are Organization (0), Organizational Unit (OU), Country (C), and [Root].

Containers are repositories of other components and resources. These are called leaves or leaf objects by Novell. Usually these leaf objects are users, printers, servers, directory maps, and so on. Novell's use of the term leaf object can be confusing, but it makes sense if you think about it. In traditional tree discussions, a leaf is an object at the end of a branch-an object that doesn't contain any objects. Likewise, Novell uses the term to refer to a noncontainer object-an object that can't contain any objects. Therefore, if something is a "leaf object," it's at the "end" of the directory tree. It's usually a printer or a user, in most cases.

It's possible to create an unlimited number of container and leaf objects in NDS. NDS ships prepackaged with 37 types of container and leaf objects. These types enable you to manage all your network resources. If new resources are connected to the network, you can define new types of objects and then add them to the NDS namespace structure.

Because NDS is displayed in a neat, graphically arranged order, objects such as users, printers, workstations, and application servers are shown in an organized structure to the system ADMIN user. You can log in as the ADMIN user from any workstation. This enables you to manage the entire directory tree. You can add and remove users, servers, and other network resources. Users need to log in only once in order to gain access to all network resources. NDS is probably the best directory service in the business. See Chapter 18, "Directory Services," for a comprehensive discussion of this important network service.

Security Services Security is another area in which NetWare shines. As the inventor, in 1983, of usernames, passwords, and user profiles (as far as LANs are concerned), Novell set the standard for security services. The user profile information is stored on the NetWare network disk in an encrypted format. The wonderful thing about this is the fact that even at the physical server level, a user running DOS, UNIX, OS/2, or Windows cannot access these network files. In fact, all password information flows back and forth from the NetWare server to the client workstation in an encrypted format. Even the administrator cannot look at a user's password on the server. The administrator can remove and add user permissions, but only the users know their own passwords. The administrator can define how often a user must change his password and can even change a user's password, but once a password is changed by the user, no one else can read it.

Even if users get to the physical NetWare server, they have no greater access to resources than they would have on their own workstations, because NetWare security is built into the NetWare system at the lowest possible level. All attempts to access information or resources on the network go through the NetWare security services system. Novell NDS is closely tied to NetWare security as well. The security service ensures that users can access those services only in the NDS database that their passwords and privileges enable them to access. NetWare security has very few holes compared to UNIX- and Windows NT-based networks.

Database Services
Novell also made a splash early on by offering LAN database services in a client/server environment. These services make life much easier for those who are developing applications to run on Novell NetWare LANs. Because these database services provide a central repository for information on the server, users had yet another reason to make Novell the leader in LAN network operating systems for many years. Three major database management systems (DBMSs) are available on NetWare: NetWare C, NetWare SQL, and the Oracle DBMS. Here are details of each:

Btrieve is actually a database record management system, indexed with a database key, designed for easy development of vertical applications. Many corporations use the Btrieve system to store records of data on a NetWare server. Users on the client stations are then able to access these records in a speedy fashion. Btrieve has shipped with every version of NetWare since release 2.

NetWare SQL was developed in an attempt to adhere to industry standards. SQL stands for structured query language-the standard used for accessing records stored in a relational database system. SQL has many versions, but Novell tried hard to stick with the SQL standard when developing its LAN version. NetWare SQL takes record management a bit further than Btrieve-it provides the capability to access Btrieve records from multiple platforms and applications.

Oracle is the world leader in database management systems. Its SQL-based system is used by many business-critical applications in many different lines of business. All NetWare 4 and 5 servers ship with a five-user version of the Oracle DBMS.

Messaging Services
In the past few years, there have been many developments in the area of messaging services. Novell is not alone in the area of messaging services development.

From NetWare 2 through NetWare 4. 1, Novell provided a messaging service called NetWare Message Handling Service (MHS). This service provided for ease of message transmission between many front-end applications. These applications can share data over LANs and Novell WANs. The MHS service could be set up on a standalone PC on the network. It could be configured to transmit message data when the user specifies. For that reason, it could take advantage of transmitting when rates on the network are cheaper or traffic volume is lower.

When Novell acquired, then sold, the WordPerfect corporation to Corel, it kept the messaging component of WordPerfect Office and renamed it GroupWise. GroupWise has replaced MHS as Novell's messaging solution and is available as an add-on to NetWare systems, but it's also bundled with Novell's Small Business Server Suite.

Print Services
Print services in NetWare are native to the NetWare operating system environment. The basic services enable users to share up to 16 printers per print server on the network. NetWare networks are capable of having multiple print servers on the network, and the real flexibility of printing in NetWare is the fact that printers need not be attached to the actual print server in order to operate properly.

Indeed, a printer can be attached to the server, but it may also be attached to a user's workstation somewhere on the network. Although the print server still manages the printers not physically attached to it, you don't need to install print server software on workstations that are hosting network printers. All that's needed is a small Terminate and Stay Resident (TSR) program on the workstation that hosts the printer. Therefore, many combinations of printers and print servers may be configured on Novell networks.

NetWare Loaclable Modules (NLMs)
NLMs are very important to the functionality of NetWare software. Starting with NetWare 3, NLMs became a mainstay of Novell network operations. These are not applications running on top of the NOS, but, when loaded, they become an integral part of the operating system. This provides the power needed to support heavily used network services in the server. NLMs have the same access to the NetWare security services, making them safe to control and administer.

NLMs can be loaded and unloaded as needed. You can even set up batch files to load and unload NLMs when appropriate. Many toolkits are offered by Novell to aid developers designing applications to run as NLMs.

NetWare-Supported Standards
NetWare can support a variety of standards and protocols on its communication links as well as several client operating systems. Here are the major standards supported by NetWare:

Communications standards. LAN, dial-up, X.25, SNA, SDLC, ISDN, T-1, TCP/IP, and IBM 3270 Gateway connections are all supported by NetWare. In addition, Novell has its own product line of NetWare-friendly routers and bridges. The NetWare Link/64 is a device that enables NetWare users to connect geographically separated workstations at speeds between 9.6bps and 64Kbps. The NetWare Link/T- I does the same thing, except at speeds up to 2.084Mbps. The NetWare Multiprotocol Router supports IPX, IP, and AppleTalk protocols. It enables users to connect Ethernet, Token Ring, LocalTalk, and ARCnet networks in any desired combination. It also provides for a transparent use of all network resources across each individual network so that users can access all the resources on the connected networks.

Operating system clients. DOS, Windows (both 16-bit and 32-bit systems), OS/2, UNIX, and Macintosh can all be used as the client operating systems on NetWare client workstations.

Strengths and Weaknesses of NetWare
The major strength of Novell's NetWare product lies in its established history and position as the most-used LAN NOS in existence. Although Microsoft has recently stolen some of Novell's thunder, these strengths are still worth noting. First, NetWare has the best print and file server software in the business, and it's the sharing of files and printers that makes a network important and useful.

NetWare boasts the best enterprisewide directory services in the business. The NDS system discussed previously is by far the best of all LAN NOS directory services. When you follow that up with the fact that strong utilities for NetWare are available from hundreds of companies, you can see why NetWare is still a logical choice when you want to establish an enterprise network. Microsoft is very weak on the enterprise level.

Novell can use improvement in some areas. First, NetWare lags as an application server. NetWare is an excellent provider of basic file and print sharing, but when it comes to being a distributed client/server application provider, it falls flat on its face. This is an area in which Windows NT has NetWare beaten hands down.

NetWare is also poor at providing useful data for monitoring network status and overall network management. Although NetWare does have some built-in network management tools, these tools are not very powerful. Many NetWare administrators feel they're unsure as to the status of their networks-whether they are running efficiently or not.

Microsoft Windows NT
Windows NT was the follow-on product to Microsoft's LAN Manager system, incorporating backward links to LAN Manager as well as new capabilities and features that were the result of the cooperative effort with IBM to develop OS/2. "Windows NT 3.5, Advanced Server" was quite a mouthful to say and quite a departure from the traditional Microsoft peer-to-peer networking paradigm because it was a true network server operating system.

More important, Microsoft realized that server-based applications were the coming trend in network servers and designed Windows NT as, first and foremost, an application server that also handles the more traditional file and print services.

Microsoft then further developed the NT platform, giving it the same basic graphical interface as Windows 95, thus easing the transition from Windows 95's peer-to-peer LAN to Windows NT's client/server LAN.

Windows NT Server, version 3.5 had numerous problems and anomalies that seemed to present themselves almost daily, but the next release-3.5 1-was (at least for a Microsoft operating system) "rock solid"-so much so, that today, years after the release of Windows NT 4 and with Windows 2000 (previously known as Windows NT 5) ready to go, many enterprises continue to run version 3.51.

Microsoft has taken pieces of network services, combined them in Windows NT, and very effectively married these services with the applications running on the clients and servers. The network versions of Microsoft Office (Office 2000), for example, and the thousands of other applications that Windows NT is capable of supporting have provided Microsoft an extremely comfortable edge over Novell's NetWare in the number of new servers installed.

Today, anyone who wants to make it in the development of applications had better be developing for the Windows NT system. Whether one agrees with it or not, Windows is a dominant force. The next section discusses the main features of Windows NT.

Features of Windows NT
Windows NT has so many features that it's not feasible to list them all in a chapter of this size. For this reason, you should visit Microsoft's NT Web site: http: / /www - mic rosof t. com/ ntserve r. You'll find some white papers there about most of NT's features. Here's a list of the major features and a description of what they do:

NT interface-The Microsoft Windows 95 operating system user interface has been integrated into Windows NT, making the server interface easier to use and consistent with Windows 95.

Administrative wizards-These little helpers place common server tools in a single area and walk you through the steps for completing tasks such as adding user accounts, determining file and folder access, and so on. These wizards walk you through the steps involved with relative ease.

Network Monitor-Network Monitor enables you to examine network traffic to and from the server at the packet level. You can also capture traffic for later analysis. This is a nice feature for troubleshooting possible problem areas on your network. This tool shows you where the weak parts of your network are by assessing the flow of traffic. By doing this, Network Monitor can pinpoint congestion sources, and it will tell you specifically where the problem traffic is being generated.

Policy Editor and Profiles-This feature gives you the right to manage and maintain the user work environment and actions. This makes it possible for users to have the same interface no matter where they log on.

Task Manager-Task Manager is used for monitoring applications and tasks. It provides information on each application and process running on a workstation as well as memory and CPU usage. It can be handy, but to many administrators, it's a superfluous function.

Internet Information Server (IIS)-Microsoft has captured a niche with this feature. This service enables you to set up a World Wide Web (WWW) server with great ease. It's tightly integrated with the Windows NT NOS. It provides an easy way to set up Web services on the LAN server. Basically, any files that exist on a server can be advertised on the Web by using this utility. In the past, setting up Web servers was generally done on older UNIX boxes. Microsoft has come up with a graphically driven method to do what used to take hours. Before there were HTML editors, many people were forced to write HTML code using text editors. After the code was written, it would have to be transferred to the Web server either by copying it directly or by using the File Transfer Protocol (FTP). This took a lot of time. IIS allows you to do all these tasks by pointing and clicking your way through some setup sequences. This is a strong product, and Microsoft was wise to introduce IIS when it did. Note, though, that IIS is a favorite target of crackers. Visit the IIS web site (http: / /www. microsof t. com/ ntserver/web/) and especially the Microsoft security site (http: / /www. microsof t. com/ security/) frequently if your Windows NT IIS is connected to the Internet.

Microsoft Index Server-This service automatically indexes the full text and properties of all files on a Windows NT server. This comes in handy when you're searching for something particular on a Windows NT system. If you need to find a specific part of a specific file out on the network, this service enables you to do so. Also, you can search using keywords within a file. This utility ensures that all instances of the word you're searching for are found.

Point-to-Point Tunneling Protocol (PPTP)-This protocol provides a way to use the Internet to create a virtual private network (VPN). This VPN can then be used to hook up client PCs with servers. PPTP can support multiple protocols via TCP/IP connections over these VPNs.

File and printer sharing-Microsoft's Domain Service uses a flat namespace structure to define logical network names for users, printers, and other resources in a Windows NT environment. A flat namespace structure is acceptable for simple networks in single geographic locations; however, it has significant limitations in environments that are more complex. In fact, all your users and network resources are organized in one list. You can see why organizing users and network resources in one list is time consuming when you don't use hierarchical file systems. This is why Novell is still considered a better choice in this area of functionality.

Microsoft Cluster Server (MSCS)-MSCS provides automatic recovery from server and application failures by providing "clustered" offerings of important applications. MSCS lets you perform rolling upgrades on your NT servers. This ineans you can perform network maintenance without taking important data and applications offline. As long as one of the servers in the cluster is up, the applications remain intact.

Microsoft Message Queue Server (MSQS)-MSQS provides reliable delivery of messages and data across a Windows NT network. Even if the network and servers are unavailable or unreliable, MSQS uses store-and-forward techniques to ensure that the messages eventually get to where they need to go. This works by keeping a copy of the messages or data in a file queue until the destination is available to accept delivery. This is especially useful during times when the network is busy or when a specific destination workstation has failed or is offline.

SMP Server-Windows NT allows the use of Server Multiprocessor (SMP) Systems. These are very reliable, fast servers in which more than one CPU can be installed. Windows NT scales smoothly from a single CPU all the way up to an eight-way SMP server.

Windows NT-Supported Standards
Windows NT can support a variety of standards and protocols on its communication links. The major communications standards supported by Windows NT are LAN, dial-up, X.25, SNA, SDLC, ISDN, T-1, TCP/IP, and IBM mainframe connectivity. Microsoft is to be commended for ensuring that any communications link you can dream up is supported by Windows NT. If you happen to find something Windows NT has a problem with, a third-party company is always out there willing to develop a fix for your problem.

Windows NT Security
When Windows NT was introduced, it was the first time in Microsoft's history that it presented an operating system with security. Windows 3.x and Windows for Workgroups provided no password capabilities other than network login security. Any files or directories on PCs using these operating systems could be easily viewed, changed, or deleted. Windows 95/98 asks for a Windows password, but it seems to do absolutely nothing after you enter it. The Windows NT password is real-it works, and it cannot be breached easily. Security is very serious in Windows NT. From the administrator's point of view, security is highly configurable. Using what Microsoft calls User Managerfor Domains, you can assign any level of security to any user for virtually anything. The sharing properties of Windows NT mean that files, directories, and entire hard drives can be set up to allow read, read/write, delete, or ownership access to only those users with legitimate needs. Windows NT uses the Windows NT File System (NTFS) when writing its files to a drive partition. NTFS provides the owners of files, directories, and hard drives with the ability to totally control what other users on the network may see, use, copy, delete, or write, as far as these owners' files and directories are concerned. This can all be done by users with the proper privileges. This takes a lot of the load off you as the administrator because you don't have to monitor and control the security of all the files and directories. As for passwords, you can make users change them at fixed intervals. There's also a feature that ensures certain users have access to the network only during certain times of the day or night. Overall, Windows NT security is excellent.

With Windows 2000, Microsoft has introduced the Active Directory Service (ADS), a full-blown directory service to rival Novell's NDS. Chapter 18, "Directory Services," includes a more detailed look at ADS.

Strengths and Weaknesses of Windows NT
When looking at the strengths of Windows NT, you must look again at the fact that it has multiple-platform support that far surpasses the other NOS systems. Windows NT supports Intel, MIPS, PowerPC, and DEC Alpha platforms with ease. This means anyone starting a new LAN can possibly take advantage of the speed and efficiency of a DEC Alpha server as the LAN's main server. At the same time, the client workstations can be cheap, Intel-based 80486 or Pentium systems.

The next area in which Microsoft has won out over Novell is application support. Windows NT is without a doubt the best of the best when it comes to being an application server. The user never sees any differences between standalone and network versions of applications running on Windows NT networks. It's seamless and invisible to the client workstations when network resources are used for certain applications.

A third strength lies in the fact that a strong financial base is being applied toward research and development of Windows N-T, Windows NT server applications, and Windows NT capabilities. Furthermore, almost 80 percent of the application development taking place in this country is geared toward Windows NT development in general. That fact, coupled with the fact that Microsoft has pledged "undying" technical support to any of these development efforts, means Windows NT can only get bigger, better, and more reliable as time goes on. What that means for users will no doubt be better graphical interfaces, better applications, easy-to-use Internet tools, and many other possibilities

The weaknesses of Windows NT are in those areas that NetWare is strongest-security, scalability, administration and directory services.

Sometimes it seems that not a week goes by without one group or another announcing a newfound security vulnerability in Windows NT. While Microsoft is quick to fix these vulnerabilities, it does require that you visit the Microsoft security Web site frequently:
(http://www.microsoft.com/security/).

NT's scalability and directory services problems (and a large part of the administrative problems) are a direct result of the domain system used to administer versions 3.5x and 4.0. Chapter 18, "Directory Services" goes into more detail about this weakness, as well as about Windows 2000's Active Directory, which alleviates some of these problems, but is still a domain system "under the covers."

Administratively, Windows NT has been called a network manager's nightmare. Over 20 different applications must be used to administer users and servers on an NT 4.0 network. In Windows 2000, Microsoft has enabled the Microsoft Management Console (MMC) to act as a repository for many of these management functions, similar to NetWare's "ConsoleOne" and "Network Administrator" applications.