A+ESS--P15

advertisement
Course ILT
Connecting computers
Unit objectives
 Identify the components of a network
 Describe wired network connections
 Compare wireless networking
standards
 Describe the different network
architectures
Course ILT
Topic A




Topic A: Networking concepts
Topic B: Wired network connections
Topic C: Wireless network connections
Topic D: Network architectures
Course ILT
Local area network
 Located within a confined area
 Connected by wires or radio waves
 Devices communicate and share data
and services
 Each device is called a node
–
–
–
–
–
–
Computer
Router
Printer
Sensing device
Video camera
Controller
continued
Course ILT
Local area network, continued
 Host is always a computer
 Can be connected to the Internet
– Direct cable connection
– Telephone link via modem
Course ILT
Example of a LAN
Course ILT
Basic types of networks
 Peer-to-peer network
 Client/server network
Course ILT
Peer-to-peer model
 Each computer has same authority
 User decides to share resources
 User responsible for many
administrative tasks
 Windows XP and Windows 2000
Professional support peer-to-peer
 Connect to form small LAN
– Wired
– Wireless
Course ILT
A peer-to-peer network
Course ILT
Peer-to-peer authentication
 Each user enter valid user ID and
password
– Authentication
– Validation
– Logging on
 Authenticated by the client operating
system
 Local user account
– Exists only on a single computer
Course ILT
Local user account
 Collection of user information
 Includes:
– User ID
– Password
– Permissions
Course ILT
Using a shared resource
1.
2.
3.
4.
Click Start and choose My Computer
Click My Network Places
Click View workgroup computers
Double-click the icon for the computer
where the shared resource exists
Course ILT
Client/server model
 Network operating system manages
network resources on LAN
– User accounts
– Printers
– File sharing





Single network user ID and password
Authenticate against the NOS
Domain model
Administrator assigns permissions
Server stores info in database
Course ILT
A client/server network
Course ILT
Network client
 Client OS sends user ID and
password to NOS on server
 Server verifies against database
 Uses network client software on client
computer
 Network client communicates with
NOS on server
Course ILT
The logon process
1. The network client on the client computer
displays a logon screen to the user
2. The user enters his user ID and password
at the logon screen and clicks OK
3. The network client then sends this
information to the NOS for authentication
4. After the user ID and password have been
authenticated, the user can gain access to
the computer and to the network resources
Course ILT
Connections
 Established with a network adapter
 Type of connector varies with the type
of network media
 NICs send and receive data
– Half-duplex
– Full-duplex
Course ILT
Network protocols
 Languages used for network
communication
 Send data in packets
 Common protocols
–
–
–
–
TCP/IP
IPX/SPX
AppleTalk
NetBEUI
Course ILT
Activity A-1
Describing networking models
and protocols
Course ILT
Activity A-2
Identifying the components of a network
Course ILT
Topic B




Topic A: Networking concepts
Topic B: Wired network connections
Topic C: Wireless network connections
Topic D: Network architectures
UTP and STP
Course ILT
 Ethernet network
– Unsheilded twisted pair (UTP)
– Shielded twisted pair (STP)
 UTP
–
–
–
–
Cat3 - 10 Mbps
Cat5 - 100 Mbps
Cat5e - 1 Gbps
Cat6 – up to 2.5 Gbps
Cat5 installation
Course ILT
 Avoid
– Pulling to hard
– Bending it too sharply (kinking)
– Forcing it through too tight an opening
 Each network node needs its own
cable from the patch panel
– Can’t splice
– Can’t run too close to AC wires – at least
a foot apart
 Install highest quality and capacity
cable
 Can run parallel coaxial or fiber
Course ILT
Composite cable
 Combines Cat5 and other
transmission cables in a single PVC
jacket
 Makes multiple-wire installation easier
 Saves cost of future wiring
 May contain:
– Two Cat5 wires for network
– Two shielded RG-6 coaxial cables
– Fiber optic line
Course ILT
Plenum wiring
 An enclose in a building that moves air
for:
– Heating
– Cooling
– Humidity control
 Created by
– A false ceiling
– A false ceiling
– Metal duct work
 Contains high- or low-voltage wiring
continued
Course ILT
Plenum wiring, continued
 Cables must meet fire protection and
environmental requirements
 To protect:
–
–
–
–
Enclose cables in a conduit
Use cables with jackets
Use cables made with fire resistant materials
Use cables that are non-toxic at extreme
temperatures
 Plenum cabling often coated with Teflon
 TP and coax both come in plenum cable
types
Course ILT
Coaxial networks
 Supports older networks
 Contains a layer of braided wire or foil
between the core and outside
insulating layer
 Shielding protects from EMI
 Layer of plastic separates core from
insulating layer to prevent data signal
damage or loss
 Ethernet uses RG-58
 Thinnet cable
Course ILT
Thinnet cable
Course ILT
Thicknet cables






RG-8 or RG-11 cables
Dual shielding
Don’t bend easily
Carry signals up to 500 meters
Used for backbone, not node drops
RG-59 (for cable TV) and RG-6 (for
surveillance cameras) not suitable for
networks
 RG-62 used for old ARCnet networks
 Check type carefully
Course ILT
A thicknet cable
Course ILT
Coax connectors
 Thinnet cables connect using a BNC
barrel connector
 Segments use T-connectors
 Line end uses terminator
 Terminator prevents signal reflection
Course ILT
Coax cable connectors
Course ILT
NIC with coax connector
Course ILT
Thicknet connectors
 Vampire tap
 Tap contains metal spikes
 Spikes penetrate cable to make
connection
 Transceiver connects to cable via AUI
port or DIX connector
Course ILT
Thicknet vampire tap
Course ILT
Activity B-1
Examining coaxial cable and connectors
Cat5 TP cable connectors
Course ILT
 RJ-45
– Eight wires
– RJ means Registered Jack
– # is the wiring pattern
 EIA/TIA-568-A defines two wiring
patterns
– T568A
– T568B
 Pins are numbered left to right, 1 – 8
 Pins connect to colored wires
Course ILT
RJ-45 and RJ-11 connectors
RJ-45
RJ-11
RJ-45 wiring
Course ILT
Pin T568A standard T568B standard
1
Green/white
Orange/white
2
Green
Orange
3
Orange/white
Green/white
4
Blue
Blue
5
Blue/white
Blue/white
6
Orange
Green
7
Brown/white
Brown/white
8
Brown
Brown
Course ILT
EIA/TIA-568-A standards




T568A preferred for residential
T568B preferred for commercial
Both electrically identical
Pin 1 always to pin 1, pin 2 always to
pin 2, etc…
 Pick one standard and use it for all
wiring
Course ILT
Terminating cable to an RJ-45 plug
Course ILT
Terminating CatX to RJ-45 jacks
 Use an RJ-45 punchdown tool
 Expensive versions use a
compression spring hammering
action
 Produces uniform connections
 Use type 110 IDC terminals
1.
2.
3.
4.
5.
6.
Remove 1 ½” of jacket from cable
Untwist full length of exposed wire pairs
Place cable end onto jack
Arrange wires into IDC slots
Use punchdown tool
Snap on protective cover
Course ILT
TIA 570 specifications
 Specifies residential
telecommunications wiring
 Specifications include:
– Topology
– Distribution devices
– Layouts for single and multiple family
homes
– Performance criteria and field tests
– Auxiliary disconnect outlets
 Two grades – 1 and 2
Course ILT
Activity B-2
Examining twisted pair cables
and connectors
Course ILT
Fiber optic cables
 Carry light-based data through strands
of glass
 Fastest and most expensive
transmission media
 Used as backbone
 Used for long-distance lines
 Composed of:
– Glass or plastic strand (core)
– Core clad in glass tube
– Outer, insulating, rubberized jacket
continued
Course ILT
Fiber optic cables, continued
 Single-mode or multi-mode
 Issues:
– Most expensive to install and
manufacture
– Data can’t transmit through broken glass
 Benefits:
–
–
–
–
–
Not subject to EMI or wiretapping
Very high transmission speed
Little or no attenuation
Length up to 10 miles
Speeds 100 Mbps to 1 Gbps
Course ILT
Fiber optic cable connectors
Course ILT
Activity B-3
Discussing fiber optic cables
and connectors
Course ILT
Linking computers
 RS-232
 IEEE 1394/Firewire
 USB 2.0
Course ILT
RS-232
 EIA232
 Interface standard for data communications
equipment
 Specifies
–
–
–
–
–
Signal voltages
Signal timing
Signal function
Protocol
Mechanical connectors
 Employed in null-modem cables
 RS-232D uses RJ-45 connectors
 Max length is 50 feet; 500 feet for
asynchronous data
Course ILT
IEEE 1394/Firewire
 Create a peer-to-peer network
between two Windows XP computers
 Max. cable length is 15 feet
 Communication speeds of 100, 200,
and 400 Mbps
 Windows 2000 needs third-party
product for Firewire networking
 Multiple Firewire ports – can daisy
chain for more than two computers
 Place repeaters every 15 feet for max
of 237 feet.
Course ILT
Windows XP IEEE 1394/Firewire
Course ILT
1394 Connection Properties
Course ILT
USB 2.0
 No designed to establish a LAN
 Use a USB bridge device between two
computers
 Use a USB hug for more than two
computers
 Can’t direct connect two computers
USB port to USB port with a USB
cable
 USB 2.0 has data transfer rate of 480
Mbps
Course ILT
Activity B-4
Examining the IEEE 1394/FireWire
connection
Network Interface Card
Course ILT
 Adapter card
– Plugs into expansion slot
– Connects externally through USB port
 NIC ports connect to network using
cable
 Supports only one of the three:
– Ethernet
– Token Ring
– FDDI
 Multiple type of ports for different
cable types
continued
Course ILT
Network interface card, continued
 Function is to send and receive data
 Converts data into appropriate
network signal
 Transceiver makes the conversion
 May have more than one type of
transceiver
Course ILT
An Ethernet combo NIC
Course ILT
Examples of NIC cards
Course ILT
NICs




Have MAC addresses
Must match network architecture
Most all are PCI cards
Older cards
– Set IRQ, DMA, and I/O addresses
Course ILT
Activity B-5
Installing a NIC
Course ILT
Topic C




Topic A: Networking concepts
Topic B: Wired network connections
Topic C: Wireless network connections
Topic D: Network architectures
Course ILT
Wireless LAN
 Uses radio waves or infrared light
 Uses wireless NIC
 Wireless NIC uses antenna to send
and receive signals
 Popular
– Where cable is difficult to install
– Where there are mobile users
 Communicate directly or through a
WAP
Course ILT
Wired network with wireless segments
Course ILT
Wireless network benefits
 Inventory is more convenient when
employees can freely walk around the
warehouse or organization
 Devices like personal digital assistants
(PDAs) and Tablet PCs can be used in
hospital wards to track patients, and doctor
visits
 Mobile workers moving between offices,
and telecommuters coming into the office,
can more easily connect to the LAN from
almost anywhere
 Online information is always available for
research or information retrieval
continued
Course ILT
Wireless network benefits, continued
 Production on manufacturing shop
floors can be readily evaluated
 Wireless network infrastructure can be
moved to a new building more easily
 The cost of providing network access
to buildings is substantially lowered
Course ILT
WAN issues
 Slower than wired networks
 Security
Course ILT
Wireless protocols







Wi-Fi (Wireless Fidelity)
Bluetooth
802.11a
WiMax
IEEE1394
IEEE 802.11g
USB
Course ILT
Activity C-1
Comparing wireless networking standards
Course ILT
Topic D




Topic A: Networking concepts
Topic B: Wired network connections
Topic C: Wireless network connections
Topic D: Network architectures
Course ILT
Ethernet
 Most popular LAN
 Good balance between
–
–
–
–
Ease of setup
Use
Speed
Cost
 Three types
– 10-Mbps Ethernet
– 100-Mbps Ethernet
– 1000-Mbps Ethernet (Gigabit Ethernet)
continued
Course ILT
Ethernet, continued
 Most use STP, UTP or fiber-optic
cable
 Older installations use thin Ethernet or
thick Ethernet
Course ILT
Ethernet topologies
 Bus topology
 Star topology
Course ILT
Bus and star Ethernet designs
Course ILT
Comparing star and bus designs
 Star may be slower than bus,
especially with many nodes
 Star may have more data collisions
Course ILT
Combined bus and star designs
Course ILT
Token Ring
 Operates at slower speeds than
Ethernet
 Physically arranged in a star
 Protocol for data control uses a token
 All data travels in a circle (ring) on the
network
 Each node is connected to a MAU by
two wires
 Token travels up and down wires and
between MAUs
Course ILT
A Token Ring network
Course ILT
Wireless networks
 Communicate with an access point or
wireless hug
 NIC includes transceiver and antenna
 Communicates over short distances
using radio waves
Course ILT
A wireless network design
Course ILT
Fiber optic cable networks
 FDDI
 Large, fast networks
 Almost exclusively use fiber optic
cables
 Communication speeds of 100 Mbps
 Used in large commercial buildings
and backbones to join LANs
Course ILT
Activity D-1
Identifying the characteristics of the
various physical architectures
Course ILT
WAN bandwidth technologies




T lines and E lines
X.25 and frame relay
ATM
Mesh topology
Course ILT
Activity D-2
Discussing WAN bandwidth technologies
Course ILT
Unit summary
 Identified the components of a network
 Described wired network connections
 Compared wireless networking
standards
 Described the different network
architectures
Download