NETWORK COMMUNICATION TECHNOLOGY
Now a days, networking is established by connecting terminals, devices and computer across WAN, LAN and wireless.
Ethernet is a LAN technology and the most popular and least expensive mode of transferring information through a network to set up. It is based on a bus topology, but Ethernet network can be wired in a star pattern.
When Ethernet works, each computer waits for a fraction of time before sending the information through a network. s When two computers try to send information at the same time, a collision occurs. After a moment, the computers resend the information.
Ethernet can transfer information through a network at a speed of a speed of 10 megabits per second Fast Ethernet can transfer information through a network at a speed of 100 Mbps. Gigabit Ethernet is a type of Ethernet that can transfer information through a network at a speed of 1000 Mbps.
Token-ring is a type of LAN technology network that is often in large organizations, such as banks and insurance companies. A token-ring network can send information through a network at speeds of 4 or 16 Mbps.
WORKING OF TOKEN-RING
Token-ring works by passing a single token from computer to computer. The token collects and delivers information as it travels around the network. When any computer on the network wants to send data, it takes control of a free token. The computer can then transmit data. Until the token has been released by the computer can transmit. As only one computer can use the token at a time, the possibility of a collision is ruled out.
TCP/IP (Transmission Control Protocol/Internet Protocol)
TCL/IP breaks up data info small pocket for every transmission. Internet transmissions commonly use TCP/IP. When a computer sends data over the Internet, the data is divided into small pieces, or packets. Each packet contains the data, as well as the recipient (destination), origin (sender) and the sequence information for reassembling the data at the destination. These packets travel along the fastest available path to the recipient’s computer via devices called routers. Thus, this technique of transmitting package from source to destination along the best possible route is called pocket switching.
WAP or Wireless Application Protocol is an open international standard for applications that use wireless communication. Its principal application is to enable access to the Internet from a mobile phone or PDA. A WAP browser is designed to provide all of a mobile phone. WAP is now the protocol used for the majority of the world’s mobile internet sites, known as WAP sites.
A private network which is based on Internet protocols such as TCP/IP but designed for information management within a company or organization. It includes services such as document distribution, software distribution and access to databases. It is called internet as it looks like a World Wide Website and is based on the same technologies, yet is strictly internal to the organization and is not connected to the Internet proper. Some intranet also offer access to the Internet, but such connected are directed through a firewall that protects the internal network from the external Web. Sometimes a company users an extranet, which allows customers or suppliers to access part of its internet. Some banks, for example, allows their customers to access their intranet to know and print their account balance and other services.
A firewall is a general term that refers to hardware and software that restricts access to data and information on a network. One of the uses of firewall is to deny network access to outsiders. As a public network, anyone with the proper connection can access to specific, vendors and customers. To prevent unauthorized access to data and information, companies protect their intranet or extranet with a firewall.