What is a Network?

What is a Network?

A network originally referred to a state of interconnected links, forming a web-like structure. It means that the entire world can become a network. A "computer network" connects computers, dramatically changing our work and lives. The network takes connectivity between computers a step further, making it a "network of networks." Let's start with the network used in offices or schools: "LAN."

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What is LAN?

Computer networks can be divided into LAN and WAN. LAN stands for Local Area Network, which refers to networks that facilitate data or image transmission between computers within a limited area, such as an office, factory, or university campus. WAN, on the other hand, stands for Wide Area Network, using telephone or dedicated lines to connect computers in different geographic locations, such as between a head office and branch offices.

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Advantages of Using a Network

• Centralized Data Management
• Computers connected to a network can read, write, and share data on other computers' hard drives, allowing centralized management by a specific computer, which is easy and convenient.
• Effortless Data Exchange
• Data can be exchanged between computers on the network through the LAN, making data integration seamless, especially for transmitting large amounts of multimedia data.
• Simultaneous Use by Multiple Computers
• All computers connected to the network can read and write over the network using a single telephone line. Therefore, there is no need for extra telephone lines or modems.

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LAN Connection Methods

LAN connections include Ethernet, FAST Ethernet, and GIGABIT Ethernet. Ethernet can be further classified into 10BASE-T, 10BASE-5, 10BASE-2, etc. The "10" in 10BASE represents the data transmission speed on Ethernet, which is 10 Mbps (meaning 10 Mbit of data can be exchanged in one second). FAST Ethernet represents a transmission rate of 100 Mbps, while GIGABIT Ethernet achieves a rate of 1 Gbps. In a LAN environment, the transmission speed refers to how much data can be transmitted within a fixed time, indicating the "size of the pipe."

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Advantages of Constructing a Security System Using a Network

Easy Installation or Relocation

Previously, dedicated cable systems required elaborate drilling into walls for installation. However, with existing network equipment, you can easily complete the wiring using the existing network system without any hassle. For places like department stores or exhibition halls where renovations and camera position changes are frequent, network-based systems make it easy to rewire and adjust.

Remote Control and Monitoring Made Simple

Data exchange between two separated locations is one of the greatest advantages of networks. Through networks or telephone lines, remote monitoring and control can be done on a computer or monitor.

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Broadband Speed Comparison

• T1: 1.54 Mbps
• E1: 2 Mbps
• T3: 45 Mbps
• ATM: 25 ~ 622 Mbps
• Cable Modem: 27 ~ 36 Mbps

Note:
Fast Ethernet: 1000 Mbps
FDDI: 100 Mbps
Giga Net: 1000 Mbps

Broadband Types	Wired Systems	General Telecommunications and Network	ADSL
			xDSL
			Dedicated Line
		Cable TV Network	Cable Modem
	Wireless Systems	General Wireless Systems	GPRS (General Packet Radio Service)
			CDMA
			WCDMA
		Digital Microwave	Digital Microwave Radio
		Satellite Communication	Satellite Broadcast Network
			VSAT

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