Everyone knows that the biggest feature of a local area network is that it can achieve optimal utilization of resources, such as: shared disk devices, printers, etc., so that files can be called to each other within the established local area network and can be used at any time. Print on Taiwan's shared printer; of course, we can also use software such as Wingate or Sygate to share a Modem with multiple machines to access the Internet; or connect to the Internet through a proxy server to enjoy extraordinary speeds. If you have more than one computer at home, and if you want to upgrade your computer game room to an Internet cafe, then you have to consider connecting them into a LAN.

Don’t think it is difficult. In fact, if we just set up a small local area network, we only need to buy a few network cards and some data cables, and we can have enough food and clothing by ourselves. We know that Windows98 has built-in point-to-point (pc to pc) network configuration capabilities, which makes it easy to establish a small network. If your LAN has many computers, then you need a mature network operating system to manage the network, such as Windows NT, Novell Netware or Linux, etc.

If you just want to connect two PCs equipped with Windows series operating systems, we can directly connect the two PCs through the computer's serial and parallel ports and use serial and parallel communication cables (pc to pc). After the computer is connected, select Microsoft's "Dial-up Network Adapter" in "Adapters" under "Control Panel/Network" in Windows and "IPX/SPX Compatible Protocol" and "NetBEUI Protocol" in "Protocols". Then start the "Control Panel", select "Add/Remove Programs", click "Install Windows Programs", select "Communications", click "Direct Cable Connection", and then use the Windows installation disk to install. After installation, restart your computer. Select a computer as the host, right-click a drive (such as C drive) in the host's "My Computer", select "Maximum Sharing", and select the mass sharing level. Run "Direct Cable Connection" in the accessories of both machines, and on the host machine, select the communication port used. Select another computer as the client, follow the prompts, wait a moment, and the connection is completed. Open "Network Neighborhood" on the "Client" desktop, and you will find that you are no longer alone. You can access your host through "Network Neighborhood", or you can map the network drive to yourself through the "Map Network Drive" method. Virtual physical drive, what's even better is that if the host you are connected to is already on the LAN, then you can also access all online resources through the host. And when you visit, it does not affect the normal work of the host, which is especially beneficial to laptop users.

When there are more than two computers (PC), network cards, network cables and hubs (HUB) are needed.

If there is no network card in the LAN, it is like a river without bridges on both sides. Network card is the abbreviation of NIC (NETWORK Interface Card), which is one of the most basic components of a local area network. The network card is installed in the expansion slot of network computers and servers and serves as the physical interface between the computer and the network. Therefore, it can simply be said that the network card is a bridge for receiving and transmitting data. According to the transmission rate, network cards can be divided into: 10Mbps network card (ISA socket or PCI socket), 100Mbps PCI socket network card, 10Mbps/100Mbps adaptive network card and Gigabit network card. At present, the 10Mbps ISA socket network card still occupies a certain market share with its low price. However, due to the low network transmission rate of the 10Mbps ISA socket network card and occupying a large amount of CPU resources, it is only suitable for those LANs that do not have high speed requirements. I recommend using a 100Mbps PCI socket network card or a 10Mbps/100Mbps adaptive network card. It is not expensive and can be adapted to application environments with a large number of users, large amounts of data transmitted on the Internet, and multimedia information transmission.

When choosing a network cable, you must first look at the interface type of the network card you purchased. There are two types of network card interfaces: RJ45 port and BNC port

The BNC port uses a thin coaxial Cable serves as a network card interface for transmission media. RJ45 is a network card interface that uses twisted pair cable as the transmission medium. The interface of RJ45 is similar to the interface of a telephone line, but the network cable uses an 8-core connector. The disadvantage of using RJ45 is that the installation cost is high, but installation and maintenance are more convenient. , so we generally use the RJ45 interface. Hub (HUB): Depending on the number of microcomputers, the HUB is used to form a star structure. When there are many workstations, the processing rate of the HUB is far lower than the transmission speed of the communication line, causing a bottleneck problem. Therefore, you can choose a switch if possible. The domain composed of a Hub is called a conflict domain. That is to say, when any computer on the network sends and receives data, all other computers can receive it, and these computers cannot send and receive data at the same time, otherwise a collision will occur (CSMA /CD protocol prevents collisions).

In addition, each computer connected to the Hub must detect the destination address of the received data to confirm whether it has received its own communication information. Therefore, the computer CPU usage is high and the overall network communication efficiency is low. It is only suitable for small workgroup levels. application.

The functions of a hub (HUB) are:

(1) Each twisted pair interface is only connected to one workstation (network card), and signals are transmitted point-to-point.

(2) When a certain port receives a signal, HUB will reshape it and broadcast it to every other port.

(3) HUB itself can automatically detect signal collisions and send out signals immediately when collisions occur. The blocking (jam) signal notifies other ports.

(4) When the transmission line or network card of a certain port fails, the HUB automatically isolates the port so that it does not affect the normal operation of other ports. Since the 100M hub is relatively small Expensive, we usually choose a 100Mbps network card and a 10M hub, and later upgrade to a 100M hub as needed.

OK! The components required for the LAN are all ready. Now let me follow you step by step to set up a LAN bar based on Windows2000 Professional, the most stable personal operating system at the moment.

If you set up a small local area network, it will be easy to handle.

Buying a HUB or a switch or a router can create a small LAN. As for the models of these devices, it depends on the number of computers in the LAN you want to connect.

If you want to set up a large LAN, it will be a bit troublesome, but you can consult experts, and there are already similar questions and a good answer here, you can check Checked. .

To access the Internet on two computers, first make network cables, and then change the workgroup of the computers to the same one (right-click My Computer--Properties--Network Identification--Properties/Look at the two computers) Are the working groups using the same one? If they are different, it will not work. They must be changed to the same working group.) Then the IP numbers cannot be the same. For example, if one is: (192.168.1.3) and the other one needs to be changed to (192.168.1.5), otherwise it will not work. The IP will conflict when surfing the Internet, and then just connect to the router

2.★Suppress the twisted pair RJ-45 crystal head

Both ends of the twisted pair pass RJ- To connect the 45mm crystal head to the network card and the hub, the crystal head needs to be pressed at both ends of the twisted pair. To press the crystal head, you need to use special clamping pliers to make it according to the following steps:

1. Strip the wire

< p>Use the cutting edge of the wire clamping pliers to cut the wire ends neatly, and then insert the twisted pair end into the wire stripping blade so that the wire ends touch the front baffle, then hold the clamping pliers moderately and slowly rotate the twisted pair. Cut the protective rubber of the twisted pair with the edge of the knife, take out the end and remove the protective rubber;

Note: Do not hold the clamping pliers too hard, otherwise the core wire will be cut;

The length of the stripped wire is 13mm to 15mm, not too long or too short.

2. Cable management

Twisted pair wires are made of 8 colored wires twisted in pairs. Arrange them in parallel according to orange and white, orange, green and white, blue and blue and white. , green, brown, white, and brown are arranged in parallel, and after finishing, trim the front end with a wire trimmer;

Note: You do not need to arrange the wires according to the above colors, but the wiring order of the connectors at both ends of the twisted pair is They should be consistent, otherwise normal communication will not be possible.

3. Plug in the wire

Pinch the crystal head with one hand, and push the side with the shrapnel downwards on the crystal head. Use the other hand to flatten the twisted pair and arrange it with a little force. The wires should be inserted into the wire trough in the crystal head in parallel, and the tops of the eight wires should be inserted into the top of the wire trough;

4. Press the wires

After confirming that all wires are in place, place the crystal head Insert it into the clamping slot of the clamping pliers, pinch the clamping pliers several times, and compress the thread head tightly.

Repeat the above method to make the other end of the twisted pair and it is finished. It is best to check it with a multimeter before use. An open circuit will cause communication to be impossible, and a short circuit may damage the network card or hub.

★Twin-computer interconnection twisted pair

If you only connect two computers at home, you can directly connect the two computer network cards without a hub by making a twisted pair as shown below Communication can be implemented using the RJ-45 interface, which is faster than using coaxial cables, saves materials, and of course costs.

★Making coaxial cable BNC connectors

Both ends of the coaxial cable are connected to the T-shaped BNC connector through the BNC connector, and the network card is connected through the T-shaped BNC connector. Networking with coaxial cable requires Make BNC connectors on both ends of the coaxial cable. BNC connectors include crimped, assembled and welded types. Making crimped BNC connectors requires special wire clamps and electrician's knife. The steps for making a crimped BNC connector are as follows:

1. Stripping

The coaxial cable from outside to inside is protective rubber, metal shielded network cable (ground shielded wire), and milky white transparent insulation layer and core wire (signal wire). The core wire is composed of one or several copper wires. The metal shielded network cable is a metal mesh woven by metal wires. The inner and outer conductors are filled with milky white transparent insulation, and the inner and outer conductors remain the same. The shaft is solidly called coaxial cable.

Use a knife to peel off 1.5cm of the outer protective rubber of the coaxial cable. Be careful not to cut the metal shielding wire. Then peel off 0.6cm of the milky white transparent insulation layer outside the core wire to expose the core wire.

2. Connect the core wires

The purchased BNC connector consists of three parts: the BNC connector body, the shielded metal sleeve, and the core wire pins. The core wire pins are used for connection. Coaxial cable core wire; after stripping the wire, please insert the core wire into the small hole at the end of the core wire pin, and clamp it firmly with the small slot in the front of the special wire clamp to compress the core wire into the small hole.

You can use a soldering iron to solder the core wire and the core wire pin. Put a little rosin powder or neutral flux into the small hole at the end of the soldering core wire pin and then solder. When welding, be careful not to expose the solder. The outer surface of the core wire pin will cause the core wire pin to be scrapped.

Note: If you don’t have special wire clamping pliers, you can use electrician’s pliers instead, but be careful not to deform the core wire pins too much, and compress the core wire tightly to prevent poor contact.

3. Assemble the BNC connector

After connecting the core wires, first insert the shielded metal sleeve into the coaxial cable, and then remove the core wire pins from the tail hole of the BNC connector body Insert forward so that the core wire pins extend outward from the front end, and finally push the metal sleeve forward so that the sleeve clamps the outer metal shielding wire on the cylinder at the rear of the BNC connector body;

4. Crimp the wire

Keep the sleeve in good contact with the metal shielded wire, and clamp it firmly with the hexagonal bayonet on the wire clamp to make the sleeve deform into a hexagonal shape. Repeat the above method to make a BNC connector on the other end of the coaxial cable and the production is complete. It is best to check with a multimeter before use. Open circuits and short circuits will cause communication failure and may damage the network card or hub.

Note: You need to use a small screwdriver and electrician's pliers to make an assembled BNC connector. After stripping the wire as mentioned above, insert the core wire into the core wire fixing hole, and then use a small screwdriver to fix the core wire. The outer metal shield Twist the wires together, fix them in the shielded wire fixing sleeve with electrician's pliers, and finally screw the tail metal to the BNC connector body.

To make a welded BNC connector, you need to use a soldering iron. After stripping the wires according to the above method, you only need to use a soldering iron to solder the core wire and the shielded wire to the soldering points on the BNC head, and put on the hard material for insulation. Just use the sleeve and soft material tail sleeve.

★Homemade terminal resistor

Bus type network coaxial cable needs to be equipped with 50 ohm terminal resistors at both ends, and one end has a grounding ring. A homemade terminal resistor can be made by using a BNC connector and welding a 51 ohm resistor between the core wire and the shell of the BNC connector (because the resistance specification does not have a 50 ohm resistor) to form a terminal resistor, and a wire is drawn from the outer layer as a grounding Wire.

After the network cable is made, you can install the network card and connect to the network.

Install the network card

The network card is one of the important components of the network. The quality of the network card directly affects the operating status of the network. Installing the network card includes hardware installation of the network card, connecting the network cable, setting the network card working status and installing the network card device driver. The following discusses the relevant content of installing the network card.

★Hardware installation of the network card

1. Turn off the power of the host, unplug the power plug, and open the chassis;

2. Take out the network card from the anti-static bag, Find a suitable slot for the network card according to the length of the gold finger on the bottom of the network card (the gold finger on the bottom of the ISA card is slightly longer than the gold finger on the PCI card); the PCI slot (white) is in the middle of the back of the motherboard, and the ISA slot (black) is on the right side of the motherboard. Rear side;

3. Unscrew the screws fixing the dust-proof sheet on the rear baffle of the chassis, remove the dust-proof sheet, and expose the strip window;

4. Align the card Align the slot with the metal interface baffle with the output interface facing the back of the chassis, and then press the card down smoothly into the slot with appropriate force;

5. Fix the metal baffle of the card with screws on the screw hole at the top of the bar window. This small screw not only fixes the card, but also effectively prevents short circuits and poor contacts. It also connects the public ground wire between the network card and the computer motherboard.

Note: There are many integrated circuits on network cards and motherboards that are easily damaged by static electricity. It is best to place the card in an anti-static bag before installing it, and then carefully remove it from the static bag during installation; Before touching the card, touch the ground or wall with your hand to release the static electricity on your body; when holding the network card, try not to touch the integrated circuit chip and the gold finger on the bottom of the card.

★Connect the network cable

1. Connect the RJ-45 interface

In the star network, use a twisted pair cable to connect the network card to the hub. Just plug the crystal head into the RJ-45 interface of the network card and hub like a phone plug.

2. Connect the BNC interface

Bus-type networks use T-shaped BNC connectors to connect the network card and computers on both sides in series. When connecting, insert the female connector in the center of the T-shaped BNC connector. In the network card BNC male plug, the male plugs on both sides of the T-shaped BNC connector are plugged into the BNC female connectors of the two cables, and the computers on both sides are connected through the two cables.

Note: After inserting the female connector into the male connector, it needs to be rotated 90 degrees to make the bayonet on the connector in place to maintain good contact;

If there is a server, please connect it to the end on, as the first computer on the network.

The free connectors at the edges of the two T-shaped BNC heads at the end must be plugged into 50 ohm terminal resistors. One of the two terminal resistors has a grounding ring at the end, and the grounding ring should be well grounded. , to prevent interference and leakage.

3. Inspection and troubleshooting

Use a twisted pair to connect the hub and the network card. After turning on the power of the host and the hub, check the hub and There is a pulse signal between the network cards. If you see the LEDs on the hub and the network card flashing intermittently, it basically means that the network card is working normally.

After installing the dual-port network card, do not connect the cables temporarily and turn on the computer power. If both LED indicators on the network card are on, the interface mode of the network card is BNC state; if only one LED indicator is on, Then the interface mode of the network card is UPT (RJ-45) state. If the current interface state of the network card is not the state you need, please run the setup program in the network card program floppy disk to set it.

The serial connection method of the bus-type network is prone to failure. When checking, the method is to start from the server and eliminate it in sections. That is, starting from the workstation closest to the server, first disconnect all subsequent workstations, move the 50 ohm terminal resistor to the computer, and check whether this workstation can access the Internet. If it can access the Internet, then connect to the adjacent third workstation. 2 workstations, determine whether they can access the Internet, and proceed in this way until the faulty site is found. Under normal circumstances, thin cable network faults are mainly caused by open circuit or short circuit. They mainly occur at the joints. You can use a multimeter to disconnect in the center of the bus for testing. If the terminal resistor is installed, the resistance should be 50 ohms. If the terminal resistor is not installed, the resistance should be 50 ohms. It should be infinite. If the 50 ohm terminal resistor is not installed at both ends of the trunk line or the terminal resistor is loose and an open circuit occurs, it will cause abnormal network communication.

★Network card working status setting

Network card working status setting mainly refers to IRQ interrupt setting and I/O address setting. For some dual-port network cards, the interface connection method also needs to be set. Here we take the common NE2000PnP compatible network card as an example to discuss how to set the working status of the network card.

The NE2000PnP dual-port network card comes with a program floppy disk, which contains the network card settings, diagnostic programs and user manual. When the NE2000PnP dual-port network card leaves the factory, the network card is set to non-PnP mode, the IRQ is set to 3, the I/O address is set to 300H, and the interface connection mode is BNC. To set and change the working status of the network card, you need to run the program SETUP.EXE in the network program floppy disk. The operation steps are as follows:

1. In DOS state, insert the installation floppy disk into floppy drive A, type SETUP to enter the main menu;

2. In the main menu "SETUP Main Menu" Select the "Adapter Configuration" option to enter the settings menu;

3. Select the "Change Configuration" option in the menu "Adapter Configuration Menu" to enter the change settings dialog box;

4. In the change settings dialog box, there are three options in the "Operation Mode" column. If you select "Jumperles" (jumper mode), you can set the IRQ and I/O address yourself. If you select "Plug & Play" (Plug and Play) Use) or "AutoSense" (automatic detection) mode, the system automatically selects the IRQ and I/O address for you;

Currently, most network cards support plug-and-play, if your operating system (such as Windows 9X), motherboard BIOS and network card can all support plug-and-play very well. It is recommended to select the "Plug & Play" mode, and the system can automatically set the IRQ interrupt and I/O address settings.

If your motherboard BIOS does not support plug-and-play, such as the 486 motherboard, you must select "Jumperles" (jumper mode) to set the working status of the network card by yourself; some motherboard BIOS and operating systems (including Windows 9X) are compatible with that Plug and play support is not good. When the network card driver cannot be installed or a resource conflict occurs, you can select "Jumperles" (jumper mode) to set the working status of the network card yourself.

5. After setting, the system. You will be prompted whether to save. If you select "YES", the system will store the settings in the EEPROM on the network card;

6. After returning to the previous "Adapter Configuration Menu" menu, you can choose "Run Diagnostics" option, test the settings of the network card. If it fails to pass the test, please reset it.

In the root directory of the NE2000PnP network card program floppy disk, MOD9008.EXE can be used to change the "Jumperles" of the network card. Jumper mode), "Plug & Play" (plug and play) and "AutoSense" (automatic detection) mode; DIAG.EXE can be used to change and test the working status of the network card.

The above programs all need to be run in DOS state. The setting test method is similar to the above content and will not be described here.

★Install the network card device driver

The following three methods can be used to install the network card (network adapter) device driver:

Method 1: Open after the hardware installation is completed When using the computer, Windows 9X automatically detects the existence of the network card, and when the screen of finding the new hardware device appears, you can follow the prompts to install it;

Method 2: Windows 9X starts and the screen of finding the new hardware device appears. When the screen appears, select the "Do not install the driver, Windows will not prompt you again" option, and then use "Control Panel"/"Add New Hardware" to install it.

Method 3: When Windows 9X starts and the screen of finding a new hardware device appears, select the "Do not install the driver, Windows will not prompt you again" option, and then use "Control Panel"/"Network" to install it .

The above three interfaces for installing network card drivers are slightly different. However, for non-plug-and-play network cards and non-plug-and-play motherboards, the system cannot automatically detect the network card and can only use the latter two. method to install. Since installing a network card (network adapter), adding client software, adding network protocols, and setting network service functions can all be done through the "Control Panel"/"Network" dialog box, this article discusses the third method.

The following uses the most commonly used NE2000 compatible network card as an example to discuss the specific steps for installing the network card device driver through the "Control Panel"/"Network" dialog box.

1. Start the computer and enter the Windows 9X desktop;

2. Select "Start"/"Settings"/"Control Panel";

3. In "Control Panel", open the "Network" window;

4. In the "Configuration" tab of the "Network" window; select the "Add" button to open the "Selected Network Component Type" window; < /p>

5. After selecting "Adapter" in the "Click the component type to install:" selection box in the "Selected Network Component Type" window, select the "Add" button to open the "Selected Network Adapter" ” dialog box;

6. Select the manufacturer of the network card in the “Manufacturer” selection box on the left side of the “Select Network Adapter” window; select the network card name in the “Network Adapter” selection box on the right side; < /p>

Note: For NE2000 compatible network cards, select "Novell/Anthem" in the "Manufacturer" selection box on the left, and select "NE2000 Compatible" in the "Network Adapter" selection box on the right;

If your network card is not in the "Selected Network Adapters" window, please click the "Have Disk" button on the lower right side to open the "Have Disk" dialog box; in the "Have Disk" dialog box, click " Click "Browse", select the network card driver in the network card driver floppy disk, and press the "OK" button; the system will read the network card driver information in the floppy disk.

7. After pressing the "OK" button, for non-plug-and-play NE2000 compatible network cards, the system will display the "NE2000 Compatible Properties" dialog box. In this dialog box, there is " "Configuration Type", "Interrupt IRQ", and "I/O Address Range" three selection boxes. If there is a "#" in front of the resource set in the box, it means that the value is the setting value of the current hardware; if the resource set in the box There is an "*" in front of it, indicating that the value conflicts with other hardware, and other resources need to be selected in the selection box to avoid conflicts;

8. Follow the prompts to "Insert the Windows 9X installation CD" and give Exit the installation directory to complete the installation.

★Add network protocol

After the installation of the network card device driver is completed, follow the prompts to restart. In the "Control Panel"/"Network"/"Properties" tab, "The following are installed" The Network Components window will typically have the following entries:

Microsoft Network Client - software used to connect to other Microsoft Windows computers and servers in order to share files using those computers and printers;

"NetWare Network Client" - software used to connect to a NetWare server to use shared files and printers on it;

"Novell/ Anthem NE2000" - the current network adapter (i.e. network card), which is the hardware that physically connects the computer to the network;

"IPX/SPX compatible protocol" - used by NetWare and Windows NT servers and Windows 9X computers Communication language, two computers must use the same protocol to communicate with each other;

"NetBEUI" - protocol used to connect to Windows NT, Windows for Workgroups or LAN Manager servers.

If you are not connected to the NetWare server, you can delete the "NetWate Network Client" entry; just use one of "IPX/SPX Compatible Protocol" and "NetBEUI" to communicate in the Windows 9X peer-to-peer network . Windows 9X can load multiple network protocols at the same time, but the protocol configurations of multiple machines in the network must be consistent. For example, they all use "IPX/SPX compatible protocol" or "NetBEUI". Using too many protocols will slow down the network speed. slow.

If you want to log in to the NOVELL network, you should set up the "IPX/SPX compatible protocol"; if you log in to the Windows NT server, you should add the protocol according to the requirements of the network administrator; if you want to connect to the Internet through the Windows NT server The "TCP/IP" protocol must be added.

If there is no protocol you need in the window of the "Properties" tab of the "Control Panel"/"Network" dialog box, please add it as follows (take adding the "TCP/IP" protocol as an example) :

1. Select the "Add" button in the "Control Panel"/"Network" dialog box to open the "Selected Network Component Type" window;

2. In the "Select After selecting "Protocol" in the "Determine Network Component Type" window, press the "Add" button to open the "Select NetTrans" dialog box;

3. In the "Manufacturer" window of the Select Network Protocol dialog box Select "Microsoft" and select "TCP/IP" in the network protocol window;

4. Press the "OK" button to complete the installation.

After completing the above work, you can log in to the network, but you must also make some settings according to the requirements of the network. For specific methods of logging in to the network, please refer to the following sections.

★How to troubleshoot network card installation

If you cannot install the network card driver or cannot log in to the network after installing the network card, please check and handle according to the following steps:

1 .Select the "Control Panel"/"System" icon to open the "System Properties" window;

2. In the "View device list by type" in the "Device Management" tab of the "System Properties" window, Double-click the "+" sign in front of the "Network Adapter" entry to expand it, and the current network card should be listed under it;

3. If there is no "Network Adapter" entry in the "Device Management" tab or the "Network Adapter" entry in front of the current network card There is an "X" mark, indicating that the system cannot recognize the network card. Possible reasons include improper installation of the network card driver, improper installation of the network card hardware, network card hardware failure, etc.;

4. If there is a circle in front of the network card "!" indicates that the system has found the network card, but the network card is not working properly. Please select the network card and press the "Properties" button to open the "Network Card Properties" menu;

5. If the network card is not working properly, The fault type and recommended solution will be given in the "Device Status" column of the "General" tab of the "Network Card Properties" window; if there is a resource conflict, it will usually be given in the "Conflict Device List" in the "Resources" tab. The device that conflicts with the network card and the conflicting IRQ interrupt number or I/O address.

For some PCI network cards, resource conflicts cannot be checked using the above method. You can select "Start"/"Programs"/"Accessories"/"System Tools"/"System Information" to open "Microsoft System Information" Window, double-click the "+" sign in front of the "Hardware Resources" entry in the "System Information" box of the left window to expand it, and you can check the resource conflict.