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As a computer technician, you must be able to install and configure a network adapter. Most new computer motherboards have an integrated networkinterface. In case you are required to install an additional networkadapter or install it on a nonintegrated motherboard, you must know how to complete the required tasks such as obtaining the networkconnection and configuring the properties of networking protocol. This section covers a brief study of network related exam objectives.

Installing and configuring network cards

Most new desktops come equipped with built-in network adapters. In newer computers, the networkinterface is integrated with the motherboard. But you might have to install, replace, or upgrade networkadapters in some old desktops. For example, you might be asked to replace a 10 Mbps network adapter with a 10/100 Mbps fast network adapter.

Installing a network adapter. When installing a networkadapter, you will need to make sure that:

• The adapter is compatible with the existing computer hardware.

• The adapter driver is meant for the operating system installed on the com- puter.

• The operating system supports the adapter driver. • Whether the adapter is PnP or not.

• The adapter driver is available for installation if it is not automatically installed by the operating system.

The following exercise explains the steps involved in installing a network adapter:

1. Turn off the power to the computer.

2. Remove the computer case cover. Locate an expansion slot and remove the plastic or metal strip that covers the case opening.

3. Insert the networkadapter into the expansion slot and tighten the screw, if required.

4. Put the computer case cover back and tighten the screws.

5. Obtain a networkpatch cable and connect it to the RJ-45 socket provided on the network adapter and the wall outlet.

Configuring the network card. Most new networkadapter are PnP-compatible. PnP adapters are automatically detected and configured by most operating systems. This configuration includes setting aside system resources such as IRQ, I/O, and DMA for the adapter as well as installation of an appropriate driver.

In case the networkadapter is not PnP, you will be required to install the network driver manually. You will need to obtain the driver, which may be available either on the CD-ROM accompanying the networkadapter or from the vendor’s web site. On Windows XP and Windows 2000 Professional computers, you can use the Add/Remove Hardware applet in the Control Panel to add the network adapter. The Device Manager snap-in can be used to install the networkadapter device driver.

Troubleshooting Techniques

The following sections cover some of the common networkproblems and basic troubleshooting techniques.

Status indicators

One of the easiest methods to troubleshooting networkconnectivity is to check the visual status indicators on networkdevices. Almost every networkdevice has some form or other visual indicator that can help find out if the device is working or not. Some networkdevices have LEDs that change color according to the condition of the device or an interface of the device.

The following list provides guidelines for diagnosing a connectivity problem depending on the status of the LED lights:

No light or yellow

The device or the port is not operational. It is either not connected or is faulty.

Solid green

The device or port is connected but there is no activity on the port.

Flashing green

The device or the port is functioning properly. It is transmitting and receiving data as expected.

Flashing amber

The network is congested and collisions are occurring on the network media. Certain devices provide separate LEDs for power, activity, and networkcolli- sions. Each of these LEDs can be a good indicator of the connectivity problem.

Troubleshooting network media

The cables and connectors used to interconnect networkdevices are often the cause of a networkconnectivity problem. Some of the key points to remember while troubleshooting network media are as follows:

• Verify that a correct cable type and connectors are used and that they are properly attached.

A+ Essentials

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• The total length of a cable used to connect devices must not exceed the specifications.

• UTP cables are also prone to interferences generated by crosstalkand electro- magnetic interferences. UTP cables should not be run in areas of high EMI (such as near transformers or beside high-voltage electric cables). For ceilings and ducts, a special type of cable known asplenum-rated cable should be used.

Troubleshooting network devices

The following are some of the common problems with network devices:

• If a hub fails, all computers connected to the hub will experience connectiv- ity problems.

• A failed switch will also result in connectivity problems to all computers in the network segment.

• Routers are used to connect networksegments. If a router fails, computers on one of the networksegments will not be able to connect to any other net- work segment.

Troubleshooting wireless connectivity

The following list provides a quickreview of the factors that may affect the wire- less networks:

• Wireless signals degrade as they travel away from a wireless signal-generating device such as the access point. This degradation or attenuation of signals is caused by several environmental factors such as EMI, RFI, walls, etc.

• Make sure that the wireless devices such as wireless router, access points, and wireless adapters all support the standard used on the network.

• TheService Set Identifier (SSID)enables wireless clients to connect to a wire- less access point and access networkresources. If a wireless client is report- ing connectivity problems, wireless configuration should be checked to make sure that the client is using the correct SSID.

• If a user cannot log on to a wireless network, make sure that he has sufficient permissions to log on. Additionally, confirm that the encryption and authen- tication settings are configured correctly on his computer.

Security

Security was not a big concern when computers were not networked and when the Internet was not as widely used as it is used today. Connecting to the Internet opens your computer or the entire networkto the outside world. If security methods are not implemented, the computers or the Internet may be at riskof being exploited. Security threats come in various forms and can cause loss of connectivity or loss of valuable data. As a PC technician, you are expected to have a good knowledge of basic security concepts. In this section, we will discuss some fundamental security concepts.