Networking

  Data Flow :   Simplex, Half Duplex, Full Duplex What are the types of data flow? Communication between two devices can be  simplex ,  half - duplex , or  full-duplex. What is simplex communication? 1__Simplex:  In simplex mode : the communication is unidirectional, as on a one-way street. Only one of the two devices on a link can transmit; the other can only receive . The simplex mode can use the entire capacity of the channel to send data in one direction . What is  Half-Duplex  communication? 2__Half-Duplex :  In half-duplex mode : each station can both transmit and receive, but not at the same time. When one device is sending, the other can only receive, and vice versa. NOTE In a half-duplex transmission ,the entire capacity of a channel is taken over by whichever of the two devices is transmitting at the time. The half-duplex mode is used in cases where there is no need for communication in both directions at the same time; the entire c...

  What is data representation? Data Representation :   How is data represented in the computer? Information today comes in different forms such as text, numbers, images, audio, and video.  What is a type in data structure? 1__Text : How do you represent text on a keyboard? In data communications text is represented as a bit pattern, a sequence of bits (0s or 1s). Different sets of bit patterns have been designed to represent text symbols. Each set is called a  code  .  and the process of representing symbols is called  coding . Today, the prevalent coding system is called  Unicode , which uses 32 bits to represent a symbol or character used in any language in the world.  The American Standard Code for Information Interchange ( ASCII ) ,developed some decades ago in the United States,  now constitutes the first 127 characters in Unicode and is also referred to as  Basic Latin. What is Code ? What is Coding ? What is Uncode ? What is ...

Introduction to Data Communication: When we communicate :we are sharing information . This sharing can be local or remote. - local communication usually occurs face to face . - remote communication takes place over distance. What is data ? refers to information presented in whatever form is agreed upon by the parties creating and using the data. What is data ? What are Data communications : are the exchange of data between two devices via some form of transmission medium such as a wire cable. NOTE: For data communications to occur : the communicating devices must be part of a communication system made up of a combination of hardware (physical equipment) and software (programs).  The effectiveness of a data communications system depends on four fundamental characteristics: What are the fundamental characteristics of data communication? 1__Delivery: What is delivery ?  The system must deliver data to the correct destination. Data must be received by the intended dev...

  Introduction to network .... Computer network ? What is network :  A network is the interconnection of a set of devices capable of communication.  A device can be a host such as a  large computer, desktop, laptop, workstation, cellular phone, or security system. A device in this definition can also be a connecting device. What are Connected Devices ? 1_Router which connects the network to other networks . 2_Switch: which connects devices together,  3_modem (modulator-demodulator): which changes the form of data.  These devices in a network are connected using  wired or wireless transmission media  such as cable or air. what is network criteria in data communication? What are the data communication criteria : What is Network Criteria : 1__Performance:  Performance can be measured in many ways, including transit time and response time. What are the criteria to evaluate the performance of a network ? 1_Transit time :  is the amount of ...