1. Network Systems
3.01 Understand the physical components of a network.

2. Network Technology Network Technology Network Devices
Types of Network Systems
Transmission Media
Linking to the Internet

3. Goals Understand Purpose of Network Identify Network Devices
Identify Types of Systems
Identify Network Devices

4. Network device Definition:
A device is a component used to connect computers or other electronic devices together so they can share files or resources.
Use:
Performs tasks like routing and communicating
Types of Devices:
Router, Switch,
Modem, Access Point

5. Router
Definition
A hardware device or software program that manages the paths along which information travels within and between networks
A router uses the IP address to determine the pathway.
Advantages
Intelligent software that enables it to pass data quickly across the network
Disadvantages
Requires configuration
Required for SOHO configurations

6. Switch
Definition
A device that links multiple computers, telephones, cameras, alarms, or networks on the same data connection
Provides individual connections for each host within the local network.
The switch uses the MAC address to determine the pathway.
MAC stands for Media Access Control
The MAC address is the hardware address of the NIC (Network Interface Card) on the end device.
It is unique for every device.

7. Switch Advantages Break-up collision domains (fewer collisions)
Faster transfer rate than hub
Improves the throughput of Ethernet networks
Disadvantages
Does not create IP addresses
No intelligent software

8. Wireless Access point Definition
Joins wireless clients to a wired Ethernet network
Also known as “hot spots”
Advantages
Mobility
Network flexibility
Disadvantages
Security vulnerability
Signal interference and limited number of frequencies
Placement

9. modem
Definition
Performs the functions of a modulator and a demodulator
Used with a dial-up Internet connection.
Modulator
Enables computers to interpret data received from a network
Demodulator
Allows a modem to send information formatted to be read by network computers

10. End device
Definition: A device that is either the source or the destination of a packet on a network.
Every device must have an IP address, MAC address and Network Interface Card.
Examples:
Computer, Printer, Server, VOIP phones, cameras and alarms

11. Host (computer) Definition A computing device on a computer network
Responsibilities / Tasks / Role / Functions
Manages tasks, communicates instructions, or delivers specific services to other computers, or clients, on a network
It is the destination of a message sent through a network.
It includes computers, mobile phones, scanners and printers.
Also known as…
Computer
Terminal
Node

12. Network printer Definition
A printer that allows for multiple users to print from remote locations of the network
It contains its own network interface card, and requires its own IP and MAC address.

13. server
Definition
A computer with the software capabilities that provides services to other computer programs and their users.
Types
File Server
DHCP & DNS
Database
Web
Print
Gaming
Music

14. VOIP Phones Definition
The method of delivering video and voice communications over a computer network
Advantages
Cheaper than the land lines
Disadvantages
Must have electrical current

15. Security cameras Definition
A digital camera connected to a computer network that allows the user to record video. Commonly used for surveillance.
Advantages
Powered with Ethernet cable
Small, portable and easily accessibility
Models can be wireless
Disadvantages
High network bandwidth
Requires lots of digital storage space

16. Security and fire alarms
Definition
A system in place for monitoring your home and business environment.

17. Types of network systems
Systems that provide service to users across a network

18. Personal area network (PAN)
Service Area
A network created around an individual’s personal workspace
Example
The connection between a Smart phone and a laptop

19. Local area network (LAN)
Service Area
A network created for a home or other small geographic area
Types
Physical
Wireless
Example
A network in a school or classroom

20. Local area network (LAN)
More facts
Consists of high speed network infrastructure at a single location used to deliver network applications and services
Ethernet is widely used in a LAN network.
It has a lower cost than other transmission media.
It is easier to use than other transmission media.
It has the capability to scale up to and past multi-gigabit speeds.

21. Transmission media Definition
Provides a path for information to be sent
from one computer to another through a
network
Types of Transmission Media:
Coaxial cable
Ethernet cable
Fiber optic cable
Wireless transmission

22. Coaxial cable Definition Cable specifically designed for carrying
an electronic signal
Two variations- ThinNet and ThickNet
Features:
Max Cable Length is 200 meters (ThinNet) or 500 meters (ThickNet)
Cost (Twisted Pair < Coaxial < Fiber Optic)
Ease of Installation (Moderately difficult to install)
Susceptible to EMI and RFI interference
Consists of four layers of material to reduce interference

23. Twisted pair cable Definition Cable commonly used in high-speed wired
computer networks
Features:
Cable Length (Up to 100 meters)
Cost (Twisted pair is the cheapest)
Ease of Installation (Easy to install)
Susceptible to EMI and RFI interference
Twisted pair wiring reduces interference
Types
Straight-through
Crossover
Rollover (console cable)

24. Unshielded twisted pair (UTP)
Found in Ethernet and phone systems
Most common type of cable used for computer networks.
Used for short to medium distances (up to 100 meters)
Not shielded against EMI or other
interference

25. Shielded twisted pair (STP)
Found in Ethernet and phone systems
Shielded to protect against EMI
More costly than UTP
Used for short to medium distances (up to 100M)

26. Fiber Optic cable Definition
Cable made of super-thin filaments of glass or
other transparent materials that can carry beams
of light
Features:
Cable Length (Longest transmission, use of light)
Cost (Fiber Optic is most expensive)
Ease of Installation (Difficult to install)

27. Fiber Optic cable More Features: Less susceptible to interference
Data can be sent at the speed of light.
A LASER transmitter encodes frequency signals into pulses of light: ones and zeros are sent through the cable.
The receiving end of the transmission translates the light signals back into data which can be read by a computer.

28. Ethernet standards
The Institute of Electrical and Electronics Engineers (IEEE) defines wired transmission in the standard.
Typically written as XBaseT (X= transmission speed) T= Twisted pair cable.
Note: The first two standards listed do not use twisted pair cabling.
10Base2- Thin Coaxial cable (ThinNet)
10Base5- Thick Coaxial cable (ThickNet)
10BaseT- Original twisted pair standard
100BaseT- Fast Ethernet
1000BaseT- Gigabit Ethernet
10GBaseT- 10GB Ethernet

29. Wireless transmission
Definition
Able to connect computers to other computers and printers the same way a wired network is, but without wires.
Features:
Range (Depends on factors such as wireless card, access point, and obstacles in between)
Cost (Wireless price is dependent upon the complexity of the setup.)
Ease of Installation (Easy)
(a,b,g,n)
Interference can be caused by cordless telephones and microwaves
Wireless security includes: WEP, WPA, and WPA2

30. Wi-fi Wireless Fidelity
The original standards for wireless networks were put out by IEEE in These standards are also called Wi-Fi, or Wireless Fidelity.
SSID
The service set identifier, or SSID, is a name that identifies a particular Wi-Fi network to a wireless device.
The SSID is required, can be up to 32 characters long and is case-sensitive.

31. 802.11 Wireless standards Designation Ratification Date Wireless Band
Data Rate
802.11
1997
2.4 GHz
2 Mbps
802.11a
1999
5 GHz
54 Mbps
802.11b
11 Mbps
802.11g
2002
802.11n
2009
2.4 GHz and 5 GHz
54 Mbps to 600 Mpbs

32. wireless security
WEP
WEP or Wired Equivalent Privacy uses a 64 or 128 bit key.
WEP keys are vey insecure.
Various attacks allow users to gain unauthorized access to the network.

33. wireless security
WPA
Wi-Fi Protected Access was designed to improve upon WEP’s features.
Two improvements over WEP are:
Improved data encryption the temporal key integrity protocol (TKIP).
User authentication which allows only authorized network users access.

34. wireless security
WPA2
WPA2 added a new Advanced Encryption Standard (AES) mode with mathematically proven security.
WPA2 offers a Pre-shared key (PSK) mode for SOHO use.
The PSK may be entered as a string of 64 hexadecimal digits or a passphrase.
Shared-key WPA remains vulnerable to password cracking attacks if users rely on a weak passphrase.

35. Connecting to the internet
Internet Service Provider
In order to access the Internet and the World Wide Web you will need an Internet Service Provider (ISP)
The ISP is a company that has a permanent connection to the Internet.
A computer requires an ISP in order for communication software to work
Once again every device will need a MAC address, IP address and Network Interface Card.