Concept of data communication and Network Types
- 1. Toufique Ahmed Chandio BE MUET, ME MUET Email: [email protected]
- 2. Index • What is data communication • Digital data communication concept • Data communication Model • Mode of data communication • Introduction Network • Types Of Networks (By Size, Connectivity)
- 3. Data Communication • The Exchange of data from one point to another point (may be human or computer) through medium(Channel wireless/wire). This exchange of data is simply called data communication.
- 4. FIRST DIGITAL COMMUNICATION One of the first applications of the electricity was to extend communication range. The first communication system, i.e. the telegraph, was digital in nature. The messages were sent by turning electrical signals on and off. This system later on evolved into telephone system, where the electrical signals are varied at audio rates. However these are the examples of wired communication.
- 5. TELECOMMUNICATION The next development was to make the communication wireless that is to extend the range of communication further. For the first time the wireless or radio communication system was designed for ships at seas. These older short distance radio links have been modernized to have global connectivity with the evolution of mobile communications. And such significant advancements have resulted into a whole branch of electronics i.e. Telecommunication.
- 6. WHAT IS TELECOMMUNICATION The term telecommunication is actually composed of two words; the prefix Tele- means “over a distance”, and Communication means process of sending and receiving of information. Where as telecommunication is referred to as, the branch of electronics concerned with the information exchange by electrical means.
- 7. Communication Model • The fundamental purpose of a communications system is the exchange of data between two parties. • On the next slide Given figures presents one particular example, which is communication between a workstation and a server over a public telephone network. • Another example is the exchange of voice signals between two telephones over the same network
- 9. Source: This device generates the data to be transmitted; examples are telephones and personal computers. Transmitter: A transmitter transforms and encodes the information in such a way as to produce electromagnetic signals that can be transmitted across some sort of transmission system. Transmission system: This can be a single transmission line or a complex network connecting source and destination. Receiver: The receiver accepts the signal from the transmission system and converts it into a form that can be handled by the destination device. Destination: Takes the incoming data from the receiver.
- 10. Data Flow • Data communication between devices has categorized into three types: Simplex Half-Duplex Full-Duplex
- 11. Simplex: – In Simplex, the transmit of data is only unidirectional. Only one of two devices can send/transmit on a link at one time. The other only can receive data. – Keyboard and monitor are examples of Simplex type data transmit. The Keyboard only give input while monitor is only for output.
- 12. Half-Duplex In Half-Duplex, each device can transmit data in both direction, but not at the same time. When one device is sending data, the other only can receive. Example of Half-Duplex are police wireless remote.
- 13. Full Duplex – In this type of mode, the data can transmit in both direction at the same time. The devices can send or receive data at the same time. the every common example of full duplex is telephone. The person at both end can talk at the same time and transmit their voice from one device to another device.
- 14. What Is Network • A Network typically known as more than one devices connected in such manner through a mutual link that can share data with each other. • Basically Network means to join more than one device in a single link to save time, share data and work efficiently. Basically we have so many types of Networks, but few of them that are every common are as:
- 15. Types of Networks PAN (Personal Area Network) LAN (Local Area Network) WLAN (Wireless Local Area Network ) CAN (Campus Area Network) MAN (Metropolitan Area Network) WAN (Wide Area Network) And so many other networks that will be categorized by their specs
- 16. PAN The smallest and most basic type of network, a PAN is made up of a wireless modem, a computer or two, phones, printers, tablets, etc., and revolves around one person in one building. These types of networks are typically found in small offices or residences, and are managed by one person or organization from a single device.
- 17. LAN One of the most common, one of the most original and one of the simplest types of networks. LAN’s connect groups of computers and low-voltage devices together across short distances (within a building or between a group of two or three buildings in close proximity to each other) to share information and resources.
- 18. WLAN • WLANs make use of wireless network technology, such as WiFi. Typically seen in the same types of applications as LANs, these types of networks don’t require that devices rely on physical cables to connect to the network.
- 19. CAN Larger than LANs, but smaller than metropolitan area networks (MANs, explained below), these types of networks are typically seen in universities. They can be spread across several buildings that are fairly close to each other so users can share resources.
- 20. MAN These types of networks are larger than LANs but smaller than WANs – and incorporate elements from both types of networks. MANs span an entire geographic area (typically a town or city, but sometimes a campus). Ownership and maintenance is handled by either a single person or company (a local council, a large company, etc.).
- 21. WAN Slightly more complex than a LAN, a WAN connects computers together across longer physical distances. This allows computers and low-voltage devices to be remotely connected to each other over one large network to communicate even when they’re miles apart. The Internet is the most basic example of a WAN, connecting all computers together around the world. Because of a WAN’s vast reach, it is typically owned and maintained by multiple administrators or the public.
- 22. Let’s understand the basic types of network connectivity Broadband: It allows companies to access the Internet from a fixed location. Broadband is the successor to the old dial-up method of connecting networks Mobile Internet: Mobile Internet is used to access networks from anywhere via wireless connections. The cellular networks and communication protocols (such as 4G) make connectivity possible between the networks. For mobile internet, the higher the protocol, the higher the speed and connectivity. Virtual Private Network (VPN): VPNs are used to create a private network to exchange data securely over a public network. The transferring of data is usually secured by a method called ‘tunneling’. Typically, large companies create VPNs to allow employees and clients communicate safely. Dial-Up Connections: Dial-up networks enable TCP/IP communication over ordinary telephone lines. They use analog modems that call specific telephone numbers to make connections.