Network Engineering

Unguided Media      In unguided media transmission, messages or electromagnetic signals travel through air or space. Cables, connectors and other solid conductors are not required in unguided media systems. Wireless communication is particularly useful in those regions where cables are difficult to implement or install. The main types of unguided media are, Radio waves, Microwaves and Infrared waves. The three main types of wireless media are: Radio waves Microwaves Infrared waves Radio Wave Links      Electromagnetic waves in the frequency range of 3 kHz to 1 GHz are commonly known as radio waves. There are basically two types of configuration for electromagnetic wave transmission and reception, directional and omni-directional. In directional configuration, an antenna radiates electromagnetic e...

Data Transmission      There is a maximum limit to the amount of data that can be transmitted using any transmission medium (Shannon's Law). Each medium has its own maximum. Data transmitted as signals. The number of signals per second is the frequency of the signal. This is measured in Hertz (Hz). One cycle per second is 1 Hz. One million cycles per second is 1 MHz. Bandwidth      The maximum range of frequencies that can be transmitted is the bandwidth of the medium. This determines the maximum amount of data that can be transmitted. A coaxial cable might have a bandwidth of 10 to 100 MHz. An optic fiber has a bandwidth of up to 10^8 MHz. The higher the bandwidth the more data that can be transmitted per second, hence the popularity of optic fibers. In fact, computers cannot yet utilize the full capacity of optic fibers, that is , they cannot transmit at the speed which the fiber is capable of carrying. Channel Capacity     ...

Computer Network Topology      A network topology is the arrangement with which computer systems or network devices are connected to each other. Topology may define both physical and logical aspect of the network. Both logical and physical topology could be same or different in a same network. Network topology refers to the conceptual framework or architectural overview of a network. They give the idea of how the end systems, hardware inter-networking devices, connectors, cable types and other components in a network are interconnected. Physical topology gives the exact arrangement of computers and other networking devices within a network. It can be compared to the architectural layout of a building. Logical topology describes direction of data flow and path followed by data in a network. Messages are broken into smaller units called packets for transmission on a network. Computer networks can be configured in a number of ways. Two fundamental topology in a data ...

Computer Networks     System of interconnected computers and its peripherals like printers is called a computer network. This interconnection help the computers to share the information between them. The connection between computers in a network either wired or wireless. Classification of Computer Network Computer networks are classified based on various factors. Geographical span Inter-connectivity Administration Architecture Geographical Span :-      Geographically a network may be spanned across your table, ie, Bluetooth enabled devices, ranging not more than few meters. It may be spanned across a whole building, including intermediate devices to connect all floors. It may be spanned over a whole city. It may be spanned across multiple cities or provinces. It may be one network covering whole world.  Inter-Connectivity:-       Components of a network can be connected to each other either logically, physically or ...