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System Development Life Cycle The System Development Life Cycle (SDLC) is a process used to develop and maintain software and IT systems. It is a framework that defines the phases and activities involved in creating, deploying, and maintaining a system. The SDLC is used to ensure that a system is developed and deployed in a structured, efficient, and cost-effective manner. The SDLC has several phases, each with its own set of objectives and deliverables. The phases are typically divided into the following categories: planning, analysis, design, development, testing, deployment, and maintenance. The planning phase is the first phase of the SDLC. During this phase, the objectives and requirements of the system are defined and a project plan is created. This phase also includes a feasibility study to determine if the proposed system is viable and cost-effective. The analysis phase is the second phase of the SDLC. During this phase, the system requirements are gathered and analyzed. This p

Hard Disk Definition, Function, Work The 1950s saw the development of hard drives. They first appeared as huge discs with a 20-inch circumference that could only store a few megabytes. Initially known as "fixed discs" or "Winchesters" (a code name used for a popular IBM product). To distinguish them from "floppy discs," they later adopted the name "hard discs." Instead of the flexible plastic film seen in tapes and floppies, the magnetic media is stored on a hard platter in hard discs. Definition of Hard disk A fixed disc or hard drive are other names for a hard disc. It is said to be a data-storing rigid magnetic disc. It can be found inside a drive unit. A hard disc is a non-volatile storage device that has magnetic discs and platters that spin quickly. Non-volatile data is data that survives the shutdown of the computer. Internally, our computer systems have it installed. The hard disc, which is made up of one or more platters packed in an air

Network Layer Basic Requirement of Network Layer The network layer is used to route data between different nodes on the network. It uses addresses to be able to tell which pc to send data to. This layer can also break apart larger messages into smaller chunks to be reassembled on the opposite end. Network Layer Services Guaranteed delivery Guaranteed delivery with bounded delay In-order packet delivery Guaranteed minimal bandwidth Guaranteed maximum jitter Security services 1. Guaranteed Delivery This service guarantees that the packet will eventually arrive at its destination. 2. Guaranteed Delivery with Bounded Delay This service not only guarantees delivery of the packet but delivery inside a mere host-to-host delay sure (for example, inside a hundred msec). Furthermore, the following services could be provided to a How of products between a given source and destination. 3. ln-order Packet Delivery This service guarantees that packets arrive at the destination in

Data Reduction Strategies  Data reduction techniques can be applied 1o obtain a reduced representation of the data set that is much smaller in volume, yet. closely maintains the integrity of the original data, That is, míning on the reduced data set should be more efficient yet produce the same analytical results Data Cube Aggregation, where aggregation operations are applied to the data in the construction of a data cube. Attribute Subset Selection, where irrelevant, weakly relevant, or redundant attributes of dimensions may be detected and removed. Dimensionality Reduction, where the encoding mechanisms are used to reduce the data set size. Numerosity Reduction, where the data are replaced or estimated by alternative smaller data representations such as parametric models or no parametric methods such as clustering camping, and the use of histograms. Discretization and Concept Hierarchy Generation, where ranges or higher conceptual levels replace raw data values for attributes. Data d

RTOS Kernel Architecture For simpler applications, RTOS is usually a kernel but as complexity increases, various modules like networking protocol stacks debugging facilities, and a device I/Os are included in addition to the kernel. RTOS architecture diagram k (A) Kernel, RTOS kernel acts as an abstraction layer between the hardware and the applications. There are three broad categories of kernels (i) Monolithic kernel Monolithic kernels are part of Unix-like operating systems like Linux, F FreeBSD, etc. A monolithic kernel is one single program that contains all nine of the code necessary to perform each kernel-connected task. It runs all basic system services (i. e. process and memory management; interrupt handling and Input /Output communication, file system, etc) and provides powerful abstraction§ of the Underlying hardware. The amount of context switches and electronic communication concerning area unit is greatly reduced which makes it runs quicker than a microkernel. (ii) Microk

Round Trip Time Round trip time ( RTT ) also called round trip delay, is the time required for a signal pulse or packet to travel from a specific source to a specific destination and back again. In this context, the source is the computer initiating the signal and the destination is a remote computer or system that receives the signal and retransmits it. On the internet, an end user can determine the RTT to and from an IP (Internet Protocol) address by pinging that address. The result depends on various factors including  The data transfer rate of the source’s Internet connection. The character of the transmission medium (copper, glass fiber, wireless or satellite).  The physical distance between the supply and therefore the destination. the number of nodes between the supply and therefore the destination.  the number of traffic on the space network computer network LAN (local area network) to that the top user is connected. the number of alternative requests being

Broadcast Routing In Computer Networks When a tool has multiple methods to achieve a destination, it always selects one path by preferring it over others. This choice method is termed routing. Routing is finished by special network devices known as routers or it may be done by means of software system processes. The software-based routers have limited practicality and limited scope. A router is often designed with some default route. A default route tells the router wherever to forward a packet if there's no route found for a particular destination. just in case there are multiple methods existing to achieve an identical destination, the router will create a call supported by the subsequent information: Hop Count Bandwidth Metric Prefix-length Delay Routes may be statically designed or dynamically learned. 0ne route may be designed to be most well-liked over others. By default, the published packets don't seem to be routed and forwarded by the routers on any network. Routers

Load Shedding In Computer Networks Load shedding could be thanks to distributing demand for power across multiple power sources. Load shedding is used to relieve, stress on a primary energy source when the demand for electricity is greater than the primary power source can supply. Most buildings, including data centers, purchase electrical power from a utility provider. To reduce the cost of energy, while also ensuring continuous operation, a building operator may negotiate an agreement with the power provider to voluntarily load the shed on a pre-scheduled or on-demand basis. During load-shedding events, the building attracts power from its' secondary source(s) instead of the utility. An atypical secondary source is on-site diesel generators, on-site or contracted solar photovoltaics, or wind-based renewable power. Many utility load management programs supply price incentives for building operators to voluntarily load sheds throughout peak usage.  Load management programs are a

Criteria For Selecting A Microcontroller Microcontroller for a product can be a daunting task. Not only there are a number of technical features to consider, but there are also business case issues such as cost and lead times that can cripple a project. At the start of a project, there is a great temptation to jump in and start selecting a microcontroller before the details of the system have been hashed out. This is, of course, a bad idea. Before any thought is given to the microcontroller, the hardware and software engineers should work out the high levels of the system, block diagram, and How to chart them, and only then is there enough information to start making a rational decision on microcontroller selection. When that point is reached, there are 10 easy steps that can be followed to ensure the right choice is made. (1) Make a list of required hardware interfaces Using the general hardware block diagram, make a list of all the external interfaces that the microcontroller will ne

Myhill-Nerode Theorem In the theory of formal languages, the Myhill-Nerode theorem provides a necessary and sufficient condition for a language to be regular. The theorem is named for John Myhill and Anil Nerode, WHO established it at the University of Chicago in 1958(Nerode 1958). Statement of the Myhill-Nerode Theorem Given a language L and a combination of strings x and y, define a characteristic extension to be a string two such specifically one in all the 2 strings xz and yz belong to L. Define a relation RL on strings by the rule that x RL y if there is no distinguishing extension for x and y. It is easy to show that RL is an equivalence relation on strings, and thus it divides the set of all strings into equivalence classes. The Myhill-Nerode theorem states that L is regular if and only if RL has a finite number of equivalence classes, and moreover that the number of states in the smallest deterministic finite automaton (DFA) recognizing L is equal to the number of equivalence c

Machine Language As we have just examined that all that every single advanced circuit can distinguish just two conceivable states, which can be indicated by 0's and 1's Hence Chip additionally can be told just utilizing some blend of 0's and 1's Such a language, which contains 0's and 1's just, is called Machine Language as it is utilized to train a machine (i.e. PC). At first, there was no other than utilizing machine language , as it was the main language. The Disadvantage of machine language  (1) The speed of execution of machine language is quickest, as it is straightforwardly written in the language comprehended by the PC (the i.e. language of 0's and 1's) (2) Best for little application, uncommonly which require control of other hardware/machine, bit savvy control of information and other low-level highlights and less calculation The advantage of machine language  (1) Programming is troublesome and tedious Programmer needs to scan for the paired