ADVANCED NETWORKINGEncoding Techniques Authors NameAffiliation InstitutionCourse and UnitAbstract—This paper discusses and critically analyzestechniques for data encoding. The paper reviews the concept ofdata and signal transmission over networks through encoding.Encoding can be achieved through two level or three levelmethods. Signals are transmitted using a continuous signal thatvaries in phase, amplitude, or other property in direct proportionto that of a variable. Encoding can be analog to analog (AM, FM,PSM), digital to digital (NRZ, NRZI, ME), analog to analog, anddigital to digital (ASK FSK PSK QAM). Some of the significantrecent developments include Orthogonal frequency divisionmultiplexing and MultiplexingKeywords—discusses; critical analysis; encoding; techniques; I.INTRODUCTIONCommunication in networks requires at least two parties;the sender and recipient, along with the medium fortransmission and the message/ data to be transmitted. Allcommunications start with the sender, who must figure outhow to encode the data/ information to be sent, so as to conveymeaning. Encoding refers to the process of putting a charactersequence, such as numbers, symbols, and letters into a specialformat to enable efficient transmission and in some cases,storage. The encoded information is then decoded at therecipient end where the encoded information is encoded(converted) back into the original character sequence. Theencoding aims at producing a signal from the encoded datastream to be transmitted over a specific medium; the encodingmust take into consideration the medium for transmission.Encoding is the process of using a code to convert originalinformation/ data into a form usable by an external process.The process of encoding defines the way that signals arerepresented on a given (physical) line of communication;hence, there is a need to have a format that is standard forseamless communication [1]. The encoded signal ismanipulated in such a way that the sender and the recipient canrecognize the changes (encoding) made. Information to be sentover a network can be analog (such as voice and video data) ordigital. II.LITERATURE REVIEWNetworks have become more complex and highlyinterconnected; for instance, the World Wide Web is amongthe biggest network of interconnected computers and servers.Copious volumes of data are exchanged at any given timewithin networks, hence the need for encoding. Further, newtransmission models, such as fiber optic have been developed,requiring a standardized method of transmitting informationover different mediums until they reach their destination in adesirable format [2]. To ensure transmission is optimized, asignal has to be encoded to facilitate transmission over aphysical medium that can be a copper cable, a network cable,or a fiber cable; wireless mediums also necessitate encoding.Encoding is essential in keeping the lines balanced even if thedata keeps changing its state often enough and to make itdistinguishable from a line that is dead. For instance, if the datastream has uneven 1s and 0s, an unbalanced offset voltage willbe developed by the receiver. Encoding also ensures that long1s or 0s strings are eliminated and that over time, the totalnumber of 1s and 0s remains balanced all the time. Further,signals cannot be sent just in the forms of 0s or 1s; the signalshave to be encoded into signals having two states, such as;The absence or presence of current in a wire Two different voltage levels relative to the earthDifference in voltage between two mediums(wires)The absence or presence of lightThere are two main ways in which encoding can beachieved; two level encoding and three level encoding. In two-level encoding, the signal is encoded in such a way that it canonly take on a value that is either strictly positive (+x) orstrictly negative (-x), where x is a value of the physicalquantity that is being used to transport signals (the physicalmedium). In three level encoding, the signal can take on avalue that is strictly positive (+x), strictly negative (-x), or null(0). There are various methods for signal encoding, asdiscussed in the next section [3]. III.CRITICAL ANALYSISOF ENCODINGThe network uses standard protocols for the transmissionand delivery of data over a distance, with the network designedin layers, each performing a specific function. The standardnetwork has various layers including the physical layer (layer1), the data link layer (layer 2), and the presentation layer(layer 3). The Transmission of data is based on the TCP(Transmission Control Protocol) and it is found in layer one(physical layer), where cannel coding takes place. Data

+13062052269

info@desklib.com