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What is TCP/IP Model?                                 TCP/IP is Transmission control protocol/Internet protocol. It is a five layer protocol suite. TCP/IP is used in the internet today. The original TCP/IP model was developed as a four layer model and later it is revised into a five layer protocol suite. 5 layers of TCP/IP Model : 1. Physical layer 2. Data link layer 3. Network layer 4. Transport layer  5. Presentation layer To know more about functions of each layers refer OSI Model For detailed explanation click here for video Follow on  YouTube  and   Instagram  

What is OSI Model?                 OSI stands for Open Systems Interconnection. It was developed by International Organization of Standardization (ISO) to achieve International standards in communication. OSI Model divides the communication process into 7 layers and each layers has some specific functions.  7 layers of OSI model :        1. Physical layer        2. Data link layer        3. Network layer        4. Transport layer        5. Session layer        6. Presentation layer        7. Application layer Functions of OSI Layers : 1. Physical layer : Physical layer is the lowermost layer of the OSI model It is responsible for movement of individual bits from one node to the other node Functions of physical layer : Physical characteristics of interfaces and medium :                          The physical layer defines the characteristics of interface between the devices and the transmission medium. It also defines the type of transmission  medium. Representation of bits :            

What is Token ring method? Token ring method is a communication protocol used in Local area networks (LAN's) In ring topology, the data is transmitted based on token passing It is also called token pass method A token is an empty frame that circulates around the network In token ring method, a token is circulated throughout the network from one node to the other How data is transmitted? If  node A has to transmit the data, it waits for the frame When the frame reaches node A, the node holds the frame and attach the data to be transmitted along with the destination address and transmits the frame The frame circulates the ring until it reaches the destination Let node C be the destination, when the frame reaches destination, the destination node (node C) copies the data from the frame and sends acknowledgement to the sender (node A) When the frame reaches node A with the acknowledgement, node A removes all the data from the frame and retransmits the empty frame into the network This

 There are five types of networks  Personal area network (PAN)  Local area network (LAN)  Metropolitan area network (MAN)  Wide area Network (WAN) Internetwork (INTERNET) 1. Personal area network (PAN) : Personal area network is a network that we use for our personal needs in a short range  It is the smallest network Range - Less than 10 meters    Example : Bluetooth, Printer, Keyboard, Mouse 2. Local area network (LAN) : In local area network a group of computers are connected to each other in a small area Range - 10 meter to 1 km In LAN's, the data transfer rate will be high Resource sharing is very easy in LAN's 3.  Metropolitan area network (MAN) : Metropolitan area network is a large area formed by interconnecting various LAN's Range - Up to 100 kms 4. Wide area network (WAN) :   Wide area network is a huge geographical area  It provides connectivity to MAN's and LAN's Range - Up to 1000 kms 5. Internet : Internet is networks of networks It is the largest netwo

What is topology?                             Topology is the structure of the network of how all the components are connected to each other  (or)                            The topology of a network is the geometric representation of the relationship of all the links and linking devices (nodes) to one another  1. Bus topology:                       In bus topology, all the nodes are connected through a single cable known as backbone cable. Here the data is transmitted from one end to the other in single direction (Unidirectional) Advantages : Installation is easy Cables required is less compared to start and mesh topologies Failure of one node does not affect other nodes Disadvantages: If backbone cable fails, it affects the whole system Fault detection is difficult 2. Ring topology:                       In ring topology, each device is connected to exactly two other devices and forms a ring. Here the data flows in one direction only (Clockwise direction) In this topology, the data i

What is a network?                      A network is the interconnection of set of devices that are capable of communication. A device can be a host (or end system) such as Laptops, Computers , Phone, printers etc. or connecting devices such as routers, switch etc. These devices are connected using wired (cable) or wireless (air) transmission media called Links . All networks must have : A resource to share A pathway transfer data (Transmission media) A set of rules governing how to communicate (Protocols) Networking criteria                A network must meet the following criteria   1. Performance :                    Performance is measured in 2 ways:  Transit time  and  Response time Transit time:                 Time taken by a message to travel from one device to other. Response time:                 Time elapsed between inquiry and response.  Performance of a network depends on : No of users Type of transmission medium Capacity of connected hardware Efficiency of software