basic Networking

Text-only Preview










MoZa~ Basic Networking
2013













1


Contents
What is a computer Network? ........................................................................................................ 3
Types of Networks: ...................................................................................................................... 3
Categories of Network:.................................................................................................................... 4
Networking Hardware .................................................................................................................... 5
1. Network Interface Card (NIC) ............................................................................................. 5
2.
Network Cable ..................................................................................................................... 5
3. Hub ...................................................................................................................................... 6
4.
Switch .................................................................................................................................. 7
5. Router .................................................................................................................................. 7
6.
Bridge................................................................................................................................... 8
7. Firewall ................................................................................................................................ 9
LAN Topologies .............................................................................................................................. 10
There are six basic types of topology in networks: ................................................................... 10

Bus Network ...................................................................................................................... 11

Ring Network ..................................................................................................................... 11
The OSI Model: .............................................................................................................................. 13
Protocols: ....................................................................................................................................... 15
Network Cables ............................................................................................................................. 16









2


What is a computer Network?
Any collection of independent computers that communicate with one another over a shared
network medium


Every network includes:

At least two computers Server or Client workstation.
Networking Interface Card's (NIC)
A connection medium, ) wire or cable, or wireless )
Network Operating system software, (example: Microsoft Windows NT or 2000, Novell
NetWare, UNIX and Linux).

Types of Networks:
LANs (Local Area Networks):
Is Networks usually limited to a geographic area, such as a single building or a college
campus. (Can be small as few as three computers or hundreds of computers).

WANs (Wide Area Networks)
Wide area networking combines multiple LANs that are geographically separated.
Example: internet or Oman mobile network.

MANs (Metropolitan area Networks)
The refers to a network of computers with in a City .


VPN (Virtual Private Network)
Network used to transfer data securely on the Internet to a remote network.

...
...

...
...
..



3


Categories of Network:
Network can be divided in to two main categories:
Peer-to-peer.
Server - based.

4



Networking Hardware

1. Network Interface Card (NIC)
Any computer needs to have a network interface card (NIC) to connect to a network.
NIC used to connect the network cable to the computer, no need for this card if you are using
wireless NIC.

2. Network Cable
To connect together different devices to make up a network, you need cables.Cables are much
faster and secure (less open to hacking) than wireless connections.






5


3. Hub
A hub is a device that connects a number of computers together to make a LAN. The typical use
of a hub is at the center of a star network (see last pages about star topology)



Note: Hubs are pretty much old-fashioned now (you can't buy them any more), having been
replaced by cheap switches.









A hub is a `dumb' device: if it send a message, it sends it to every computer on the network.
This means that hub-based networks are not very secure - everyone can listen in to
communications.










6


4. Switch
A switch, like a hub, is a device that connects a number of computers together to make a LAN.
The typical use of a switch is at the center of a star network.







A switch is a more `intelligent' device than a hub: if it send a message, it checks the addressee
first, and then it only sends the message to a specific computer (no to all computers like hub).
Because of this, networks that use switches are more secure than those that use hubs, but also a
little more expensive.


5. Router
A router is a network device that connects together two or more networks.
A common use of a router is to join a LAN networks to the Internet or WAN networks.
The router joins many different networks together witch form the .





7


6. Bridge
A bridge is a network device that typically links together two different parts of a LAN.










The different between router and bridge: Router is usually used to connect a LAN to a WAN
(network to network), a bridge connects two (or more) different parts of a LAN so that they act
as a single LAN.














8


7. Firewall
A firewall is a device, or a piece of software that is placed between your computer and the rest
of the network (where the hackers are!)
If you wish to protect your whole LAN from hackers out on the Internet, you would place a
firewall between the LAN and the Internet connection.










A firewall blocks unauthorized connections being made to your computer or LAN. Normal data
is allowed through the firewall (e.g. e-mails or web pages) but all other data is blocked.













9


LAN Topologies


The word topology means `arrangement', so when we talk about the topology of a network, we
mean how the different parts are arranged and connected together.

There are six basic types of topology in networks:

Bus topology

Star topology

Ring topology

Mesh topology

Tree topology

Hybrid topology


















10


Document Outline

  • What is a computer Network?
    • Types of Networks:
  • Categories of Network:
  • Networking Hardware
    • 1. Network Interface Card (NIC)
    • 2. Network Cable
    • 3. Hub
    • 4. Switch
    • 5. Router
    • 6. Bridge
    • 7. Firewall
  • LAN Topologies
    • There are six basic types of topology in networks:
    • ׾ﰷ
  • The OSI Model:
  • Protocols:
  • Network Cables