CPU: Central Processing Unit

CPU stands for central processing unit which denotes to an electronic circuit capable of fetching input commands or instructions from memory unit. Logic and arithmetic operation care performed by the CPU and it also stored the data back to the memory device. As the name implies it is the central unit of the whole system and installed in a dedicated socket on motherboard along with a fan.

As shown in the diagram CPU is comprised two core units as ALU and CU. ALU stand for arithmetic logic unit which performs all kind of logic and arithmetic operations in system. It receives inputs of three type as status information from operations done beforehand, data which will be operated and signal from Control Unit (Silberschatz, Gagne and Galvin 2018). The other unit named Control Unit navigate the operations by sending control and signals.

Figure 1: Components of the CPU

Fetch, decode and execute are the main working functions of the CPU regardless of their origin. In the current market major manufacturer of the CPU are AMD, VIA and Intel. For mobile devices Apple, Samsung and QUALCOMM are the leading in the market.  

RAM stand for Random Processing Memory which is a volatile memory as it cannot store the memory without the power when computer is turned off. As it cannot store log term memory, it is used for short term memory. It is used to access to the memory quickly rather than sending request to the hard drivers. There are two type of RAM as DRAM and SRAM. DRAM stand for Dynamic random access memory which refreshed frequently and denotes the capacity of the RAM as well. For instance, if a computer has a 4GB RAM, the 4 indicates to the DRAM. It is used as a main memory unlike SRAM which is used for cache. It stands for static random Access Device and does not need to be refreshed dissimilar to the DRAM.

Figure 2: RAM

Persistent storage is the main storage location for all data such as operating system, files and many more. The hard drive has a capability of limited storage depends on the slots. Unlike RAM it is a non-volatile memory which is capable of storing information without power. Data stored in the device can be stored information even after having been power cycled. There are mainly two type of persistent storage as HDD and SSD. HHD stands for hard disk drives and SSD stands for solid state drive. RAM is a non- Persistent memory however, certain types such as non-volatile RAM and flash-based RAM are persistent. Persistent storage can be in the form of file, block or object storage.

RAM: Random Processing Memory

Figure 3: Persistent storage

Operating system act as a bridge between the hardware and software interface. It can be defined as integrated program which manage every operation and resources of the system. The general functionality of the operating system is to act as a base for software application in which the basic tasks are performed as keeping track of files and directories on the storage drives, sending output to the display screen, recognizing input from the keyboard. It also manage every program running on the system as well as responsible for security ensuring that unauthorized users do not access the system (Agne et al. 2015). The application software are designed to run on specific operating system. There are mainly two operating system which are majorly popular as Microsoft windows and Apple IoS. Other than this, DOS, Linux and UNIX are available in the market. There are several classification of operating system. Microsoft Windows is a family of operating systems for personal and business computers. Windows dominates the personal computer world, offering a graphical user interface (GUI), virtual memory management, multitasking, and support for many peripheral devices.

Figure 4: operating System

Real time: Responds to input instantly. General-purpose operating systems, such as DOS and UNIX, are not real-time.

Multithreading : Allows different parts of a single program to run concurrently.

Multitasking : Allows more than one program to run concurrently

Multiprocessing : Supports running a program on more than one CPU.

Multi-user: Allows two or more users to run programs at the same time. Some operating systems permit hundreds or even thousands of concurrent users.

The objective of the operating system is to provide fair and efficient sharing of resources amongst programs and user, to manage different resources of a computer system, to provide users a convenient interface to use the computer system.

Software licencing is a set of document which comprised with binding guidelines along with the distribution and use details of the software. The licence provide the rights of the application which must be followed by the user when distributing and using the software. It is mainly used to restrict copy and wrong use of software. Software licensing conditions and terms comprised with the limitations of liability, disclaimers, warranties and protections. Whenever, user is making copies of any software for downloading pirated software or distributing, loaning disks or buying a ligament software and using it on multiple system, users committing copyright infringement which is commonly known as software piracy. Such users can be held liable under criminal and civil law if found to make copies (Casado et al. 2015). The pirated software also brings risks which could damage the network through embedded malicious applications. It is mainly used to restrict copy and wrong use of software. Software licensing conditions and terms comprised with the limitations of liability, disclaimers, warranties and protections.

Persistent Storage

Clocking can be define as a search engine optimization technique where the contents presented to the end user is different from the result search by the crawlers. Crawlers are the spiders or bots. Clocking can also be define as black hat technique which is used to produce different webpage depends on the end user and search bots. If an end user tries to open a certain web page, a web page will appear which could be different when requested by search bots. The practice of clocking has been band and declared as an illegal activity or black hat SEO. According to the most popular search engine corporation Google, it violates the webmaster guidelines and also alleged for providing different results than user expected. Some most used clocking includes Inserting text or keywords into a page only when the User-agent requesting the page is a search engine, not a human visitor and Serving a page of HTML text to search engines, while showing a page of images or Flash to users. Clocking was introduced for improve the ranking of search engine. It was pretty effective to mislead the bots into getting the original content as bots could increase the traffic of the websites which will restrict the users to access the website effectively. The clocking is used as spamdexing technique as search engine poisoning and search engine spam to modify the search result. The clocking is done by modifying the file named .htaccess. Every communication device used IP addresses to access internet. Clocking can be apply on web pages. For instance, Apache server consist of a module name mod_rewrite it can be manipulated in order to apply clocking. The webmasters gathered and stored the search engine crawler or Ip address and as the users request for a web site, it checks the ip address and provide different version of the web address. If the requested IP address not belongs to any crawlers, the normal webpage is delivered. This is just the explanation of black hat clocking. There are also several type of practice followed by the webmasters. Generally, search engine rank and index web pages according to the titles, META tags and other techniques. While keeping this in mind, webmaster does the followings.

Many website are embed with more images and comparing to the contents. The issue hare is the images cannot be scanned by crawlers. So, webmasters think that cloaking could help them get top placement for relevant keywords.

Operating System

A good SEO recommends having “TEXT to HTML ratio” as high as possible. In other words, your web page should have more text (content) as compared to your HTML tags. But if anyone is writing short articles or posts, your text to HTML ratio will be very low. To avoid redesigning the website, folks choose cloaking to meet SEO guidelines

However, the IP delivery can be more effective and efficient variation of clocking. In this approach different content is delivered depends on the IP address. In this type of clocking, the crawlers never visits the original page while the end users can visit the original content. The approach is followed in heavy graphics sites which have very little textual content as images cannot be analysed by the crawlers. The IP address is used to identify the location of the request. Such information helps to provide the exact content for specific country. However, this functionality can be achieved without using the clocking.  For example, Google also used ip delivery for targeting different ads into different regions. However, IP delivery is unreliable and crude method to identify the content language. The webmasters gathered and stored the search engine crawler or Ip address and as the users request for a web site, it checks the ip address and provide different version of the web address. If the requested IP address not belongs to any crawlers, the normal webpage is delivered. This is just the explanation of black hat clocking. There are also several type of practice followed by the webmasters. Generally, search engine rank and index web pages according to the titles, META tags and other techniques. While keeping this in mind, webmaster does the followings.

Reference: 

Agne, A., Happe, M., Keller, A., Lubbers, E., Plattner, B., Platzner, M. and Plessl, C., 2014. ReconOS: An operating system approach for reconfigurable computing. IEEE Micro, 34(1), pp.60-71.

Casado, M., Amidon, K.E., Balland III, P.J., Gude, N., Pettit, J., Pfaff, B.L., Shenker, S.J. and Wendlandt, D.J., NICIRA Inc, 2015. Network operating system for managing and securing networks. U.S. Patent 9,083,609.

Kamel, M.R. and Donahue, P.W., MELROK, LLC, 2017. Energy search engine with autonomous control. U.S. Patent 9,727,068.

Liu, X., Li, Y. and Liu, K., 2015. Clocking-optimization method for figure-error balancing in complex optical systems. Optical Engineering, 54(5), p.057103.

Reeves, B., Reeves, P., Teltz, R., Reeves, D., Sirpal, S. and Tyghe, C., Z124, 2014. Multi-operating system. U.S. Patent 8,898,443.

Silberschatz, A., Gagne, G. and Galvin, P.B., 2018. Operating system concepts. Wiley.