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Ch. 3 - PC networks

1 Components

2 Shared resources

3 Network operating systems

4 Novell Netware

5 Windows NT

6 IBM LAN Server

7 Netware vs Windows NT

Ch. 3 - PC networks

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A PC network is used to share resources such as files and printers. A PC network isnormally based on Ethernet or Token Ring and consists of a number of components:

1. Cabling is used to physically connect the components together. A common type of cableused in both Ethernet and Token Ring is twisted pair.

2. Clients such as PCs or Macintoshes can be used together on the same network. Oneoften distinguishes between the hardware and the software components of a client. Oneimportant hardware component is the NIC, which stands for Network Interface Card,inside the client. The software component responsible for communication consists oftwo parts: the operating system and communication software. These two together arecalled Network Operating System. An example of a Network Operating System on aclient is DOS and IPX software.

3. Servers are used to share documents and programs. Servers are often dedicated powerfulcomputers. There are different types of Network Operating Systems for a server.Examples are Novell Netware, Windows NT and IBM LANServer.

4. Printers are common components found in a PC network.

5. Gateways, not seen in this picture, are used to translate between two applications orprotocols. Gateways are used for communication between different protocols.

Ch. 3 - PC networks

3

One of the main reasons for using local networks is to share common resources, such asprinters, files, e-mail and devices for communication.

In the picture you see a shared printer and a file server which is used to share files. Routersand gateways are used for communication to other LANs and remote devices such ascomputers and faxes.

Ch. 3 - PC networks

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After the physical network the NOS, Network Operating System, is the most importantpart in a PC network. The network operating system is responsible for the levels 3 to 7 inthe OSI model. This means that NOS is independent of the type of network. It works in thesame manner on an Ethernet as a Token Ring.

There are two types of NOS. The first type is called "peer to peer” which means that nodedicated server is needed. The other type is server based and is used for larger, moredemanding networks.

There are many vendors with their own types of NOS on the market.

The leading systems for "peer to peer” based NOS are NetWare Lite and Windows forWorkgroups.

The leading systems for server based NOS are Novell NetWare, Windows NT and OS/2LAN Server.

Ch. 3 - PC networks

5

Novell Netware has for a long time been a market leader of NOS. Netware has been on themarket since 1983 and it runs only on Intel processors.

Novell developed NetWare, which is a powerful multisession system. This means thatNetWare can handle different parallel sessions as previously only found in larger types ofcomputers.

NetWare is sold in many versions corresponding to the number of users, types ofconnections and level of security.

The client could be a personal computer with or without its own hard disc and with anoperating system such as MS-DOS, OS/2, MacOS or UNIX.

Netware handles both IPX and TCP/IP traffic over Ethernet or Token Ring.

Ch. 3 - PC networks

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In the summer of 1993 Microsoft released their new Network Operating System, NT forworkstations. The NT server followed in the autumn of 1994. The network protocols usedin NT are NetBEUI, TCP/IP, IPX and AppleTalk, which gives NT the opportunity tocommunicate with different types of network platforms. Windows NT is a multisessionoperating system. NT can run on different types of processors like Intel, Alpha andPowerPC. NT has also a good support for remote dial-in communication, called RAS(Remote Access Service).NT is normally used on top of Ethernet, but it is also possible to use in Token Ring.

Ch. 3 - PC networks

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The LAN Server was in the beginning, a product developed by IBM and Microsoft. After atime Microsoft left this project but IBM developed it further and called it IBM LAN Server.IBM chose to run OS/2 on a dedicated server. IBM LAN Server supports DOS andWindows based clients. The supported transport protocols are NetBEUI and TCP/IP. Thisgives the LAN Server the opportunity to be used in mixed environments. The IBM LANServer is not as common as NetWare or NT.

Ch. 3 - PC networks

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The two largest competitors on the NOS market are Novell with its NetWare and Microsoftwith Windows NT. Microsoft is taking more and more of the NOS market and growing veryfast.

Microsoft solutions are a little bit cheaper than the solutions from Novell. But the realadvantage is that Windows NT supports different processors and many protocols.