Chapter 3
1

Chapter 3: NETWORK CONNECTION HARDWARE
NETWORK INTERFACE ADAPTER




Provides the link between a computer and the network
Requires a device driver to perform both data-link and physical layer functions
Plugs into a bus slot or universal serial bus (USB) port on a computer
Also referred to as a network interface card (NIC)
2

Chapter 3: NETWORK CONNECTION HARDWARE
A NETWORK INTERFACE ADAPTER
3

Chapter 3: NETWORK CONNECTION HARDWARE
TRANSMISSION FUNCTIONS
 Network interface adapters perform the following functions during data transmission:
 Data transfer, buffering, and encapsulation
 Media Access Control (MAC)
 Parallel/ serial conversion
 Signal encoding and amplification
4

Chapter 3: NETWORK CONNECTION HARDWARE
HALF-DUPLEX AND FULL-DUPLEX MODES
5

Chapter 3: NETWORK CONNECTION HARDWARE 6
INSTALLING A NETWORK INTERFACE ADAPTER
IN A COMPUTER
To install a network interface adapter:
1.
Physically insert the network interface adapter card into the slot.
2.
Configure the card to use the appropriate hardware resources.
3.
Install the card’s device driver.

Chapter 3: NETWORK CONNECTION HARDWARE
A NETWORK INTERFACE ADAPTER IN A
COMPUTER
7

Chapter 3: NETWORK CONNECTION HARDWARE 8
NETWORK INTERFACE ADAPTER DEVICE
DRIVERS





Network interfaces require a device driver to provide the link between the computer and the interface.
Operating systems ship with device drivers for common interfaces.
Operating systems that support PnP detect and configure the interface automatically.
You can get drivers from the manufacturer’s Web site.
The driver configuration must match the interface’s resource settings.

Chapter 3: NETWORK CONNECTION HARDWARE
TROUBLESHOOTING A NETWORK INTERFACE
ADAPTER
 To troubleshoot the suspect network interface adapter, open the computer case and do the following:
 Verify that the interface is seated properly in the bus slot.
 Remove the card, clean the slot, and then reseat the card in the same slot or try another slot.
 Test a different interface (known to be functional) in the same slot and in a different slot
9

Chapter 3: NETWORK CONNECTION HARDWARE
HUBS, REPEATERS, AND CONCENTRATORS
 Hubs, repeaters, and concentrators are all physical layer devices that
 Amplify and repeat signals
 Extend the distance of a network
10

Chapter 3: NETWORK CONNECTION HARDWARE
AN ETHERNET REPEATER
11

Chapter 3: NETWORK CONNECTION HARDWARE 12
10BASE-T AND 100BASE-X HUBS


10Base-T and 100Base-TX/100Base-T4 standards define
Ethernet networks that function at 10 Mbps and 100 Mbps, using baseband signaling over twisted-pair wire.
10Base-T




Maximum distance limitation for each connection: 100 meters, including workstation-to-hub and hub-to-hub connections
Can have up to four hubs connected to form a hierarchical star
Includes an internal crossover circuit
Uses an uplink port to form a hierarchical star

Chapter 3: NETWORK CONNECTION HARDWARE 13
10BASE-T AND 100BASE-X HUBS (CONT.)
 100Base-TX and 100Base-T4
 There are two types of hubs: Class I and Class II.
 The maximum distance for each node connection is
100 meters.
 Class II hub-to-hub connections can be no more than
5 meters long.

Chapter 3: NETWORK CONNECTION HARDWARE
HUB CONNECTIONS
14

10BASE-T HUB
Chapter 3: NETWORK CONNECTION HARDWARE 15

Chapter 3: NETWORK CONNECTION HARDWARE 16
ROUTERS
Routers are network layer devices that connect LANs.
 Connect similar or different data-link layer LANs
 Must understand and support the network layer protocol and addressing





Perform fragmentation
Strip the data-link header and footer off received frames
Add a new data-link header and footer before transmitting frames
Use routing protocols to build routing tables and forward frames
Define separate broadcast domains

Chapter 3: NETWORK CONNECTION HARDWARE
A SIMPLE ROUTED NETWORK
17

Chapter 3: NETWORK CONNECTION HARDWARE
A ROUTED INTERNETWORK
18

Chapter 3: NETWORK CONNECTION HARDWARE
GATEWAYS



Can include the functions of all seven layers of the
OSI model
Connect dissimilar systems and protocols
Perform translation and conversion services
19

Chapter 3: NETWORK CONNECTION HARDWARE 20
SUMMARY




Network interface adapters provide the physical link between computers and the network.
Hubs are physical layer devices that amplify and repeat signals out all ports except the one they were received through.
Routers are network layer devices that forward datagrams between LANs.
Gateways translate and convert protocols between dissimilar systems.