Computer Basic Networking

What is Network

Network is a group of computers or other devices, such as printers, scanners, which communicate either wirelessly or by using a physical connection, such as an Ethernet cable or a phone line.

Advantages of Networks:-  
1.Network allow groups of users to exchange information and share data.

2.It allow easy and efficient communication system.

3.Networking reduce costs and times.

4.Networks help to speed up data sharing.

Type of Network technologies:-  

• The most common types of network technology are- 

1. Wireless (Wi-Fi, GPRS, 2G, 3G, 4G) 

2. Wire (Ethernet) 

1. wireless Network :- Wireless networks use radio waves to send information between computers. 

The 4 most common wireless network standards are-  

• 802.11b (maximum data transfers rate 11 Mbps)
• 802.11g (54 Mbps)
• 802.11a (54 Mbps)
• 802.11n (150, 300, 450, or 600 Mbps.)

 

• Advantages of wireless Networks:-

1.It's easy to move computers around, because there are no cables. 

2.Wireless networks are usually easier to install than Ethernet.

• Disadvantages of wireless Networks:-

1.Wireless is often slower than the other technologies. 

2.Wireless can be affected by walls, large metal objects. Also, many cordless phones and microwave ovens can interfere with wireless networks.

2. Wire (Ethernet) Network :-
• Wire or Ethernet networks use Ethernet cables to send information between computers.
• Ethernet is the most widely installed technology for connecting computers.
• Ethernet data transfers rate up to- 10, 100, or 1000 Mbps, depending on the type of cables used. 

• Advantages of Ethernet Networks:-

1. Ethernet networks are inexpensive and fast.
2. Very reliable.

• Disadvantages of Ethernet Networks:-

1. Ethernet network is very costly.
2. Only for short distance networks.
3. Limited mobility. 
4. Ethernet networks are very difficult to troubleshoot.

Signal

What is “Signal” 
• A signal is an electrical or electromagnetic field or current or wave that is used for carrying data from one device or network to another.   
• In a communications system, data are circulating from one point to another by electric signals.   
• Typically, a signal is created when data is sent to a device.
• Signals are go through wire or wirelessly.   
• Types of Signals: - Signals are two types –
(1) Analog Signal
(2) Digital Signal

(1) Analog Signal: – 

• An Analog signal is a continuous signal or continuous wave.
• It denoted by a sine wave and may vary or change in signal strength (amplitude) or frequency (time).
• There are many examples of analog signals around us. The sound from a human voice is analog, because sound waves are continuous. Radio waves are analog signals. 

(2) Digital Signal: –
• A Digital signal is discrete or discontinuous signal. 
• It denoted by a square wave.
• A digital signal use binary system (0 and 1) and cannot take any fractional values.
• A digital signal retains a uniform wave structure.
• There are many examples of using digital signals devices Computer, CD-DVD player, pen drive, Mobile, digital watch,Modem and many network devices.

 

Analog signal and Digital signal wave form