Frequency-Division Multiplexing (FDM) is an analog method which is used when the channel's bandwidth is higher than the consolidated bandwidths of the signals which are to be broadcasted.In FDM, different frequencies are combined into a single composite signal and are transmitted on the channel. At the receiver end, the reverse phase is applied to get the individual frequencies back for working. The entire bandwidth of the channel is divided into logical channels, and each sending device is given with the possession of a logical channel.There is a gap between the frequencies of adjoining channels to avoid one channel's frequency with ... Read More

The electromagnetic waves having frequencies from 300 GHz to 400 THz (wavelengths from 1mm to 770 nm) are referred to as infrared (IR) waves. IR uses line-of-sight propagation.Infrared light is a transmission channel whose features are necessarily different from those of the radio frequencies. A fundamental property of infrared light is that it cannot penetrate the walls. This represents that it can easily include it within a room.Another advantage of infrared communication is massive bandwidth which is available for use, but has not been exploited to its full extent.The major disadvantage is that the sun creates emission in the infrared ... Read More

TCP/IP signifies the transmission control protocol/Internet Protocol. It was created by the Defence Advanced Research Projects Agency (ARPA, later DARPA) in the late 1970s.It is a collection of communication protocol. Moreover, it involves collection and methods for managing packet transport, media access, session interaction, data transfer, email and terminal emulation.Advantages of TCP/IP ModelThe main advantages of TCP/IP are as follows −It is a broadly accepted model which can deploy effectively in all the practical networking issues.TCP / IP can also enable cross-platform communications among the heterogeneous networks.It supports connection-oriented reliable service. It defines that it maintains the transfer of data ... Read More

OSI represents Open System Interconnection. It was produced by the International Organization for Standardization (ISO) located in Geneva, Switzerland, and the consultative committee for international Telephone and Telegraph (CCITT).OSI was created to develop a frequent standard of network structure throughout the globe. It supports a general idea of inter-process communication so that any open system can technically connect with another accessible framework without any issues. OSI model is a seven-layered architecture model.Advantages of the OSI ModelThe advantages of the OSI Model are as follows −The OSI models clearly define the services, interfaces and protocols. It explains which layer's services are supported. ... Read More

The presentation layer changes the data from an application layer into the device native internal mathematical structure and encodes communicated information into a displayable output format.It executes the code changes, document compressions, security encryption, etc. It also defines the data as per the software/hardware environment of the hub. For instance, demonstrating UNIX structured data in windows.The link between the presentation layer and the application and session layer has been shown in the diagram below −It is concerned with the syntax of data.TranslationThe procedure in two frameworks are generally to exchange the data in the form of character strings, numbers etc. ... Read More

The session layer supports establishing, controlling, and eliminating a session or dialogue between the two end frameworks. It generates the session, handles the packets sent back and forth during the session and removes the session. The dialogue type/session type is also defined through half-duplex or full-duplex.The session layer also supports data synchronization and check pointing so that only the information transmitted after the point of failure should be retransmitted in the event of network failure.This layer also governs the dialogue between the two processes by deciding who can send and who can get at what point during the transmission.The session ... Read More

Physical layer is the shortest layer in the model. This layer is feasible for initiating, preserving, and deactivating a physical circuit between two end frameworks.The Physical Layer is vital for transmitting bits from one device to another device. It can change the series of bits into electric signals, light signals, or electromagnetic signals, relying on either the two hubs on a link circuit, fiber-optic circuit, or microwave/radio circuit.Passive hubs, simple active hubs, terminators, couplers, cables, connectors, repeaters, multiplexers, transmitters and receivers are the devices associated with the physical layer.The physical layer situation for the transmission channel and the data link ... Read More

OSI represents Open System Interconnection. The OSI reference model is a seven-layered architecture and is created in a hugely structured method. Each layer in the model has specific sets of procedures, functions, and protocols. One layer can communicate with an adjacent layer by using its interface.OSI model was advanced by the International Organization for Standardization (ISO) in Geneva, Switzerland, and by the Consultative Committee for International Telephone and Telegraph (CCITT).The figure given below displays the seven-layered Architecture of OSI Models, along with the protocols and interfaces.Functions of the OSI LayersThere are various functions of OSI Layers which are as follows:Physical LayerThis ... Read More

Both Hubs and Bridges are network connecting devices and both of them broadcast data to every node on a network. Hubs operate at the Physical Layer and they do not perform packet filtering or addressing function; they send the data packets to all the connected devices. Bridges connect various devices in a network.A bridge operates at the data link layer to connect multiple networks. It can read the outmost section of a data packet to tell where the message is going. A bridge can be programmed to reject packets from a particular network, so it can be used to reduce ... Read More

A VPN connects a private network to another public network, which allows users to transmit and receive data as if their computers were connected to the private network physically.MPLS is a routing technique that is used to improve the speed and control of the network traffic. It speeds up traffic flows by avoiding complex lookups in the routing table at each node as in conventional routing algorithms.Read through this article to find out more about MPLS and VPN and how they are different from each other.What is VPN?VPN stands for virtual private networks. It is a network type that is ... Read More