How RAM affects performance

How RAM affects performance

‘RAM’ and ‘ROM’ are acronyms. State what the letters RAM and ROM stand for.

• RAM - Random Access Memory
• ROM - Read Only Memory

State the differences between RAM and ROM.
ROM can only be read and not modified, whereas data can be written to the RAM by the computer.
When power is off all data is lost in the RAM, it is volitile, ROM isn't.

Explain why ROM is required by the computer.
ROM is a special type of memory needed by the computer to boot up - known as BIOS (basic input output system) it allows the che computer to be powered off and still store data. This type of memory is needed becuase the computer must be able to obtain instructions the moment it is swithed on. It must know some basics about the machine hardware: configuration settings.

Explain the function of RAM in a computer system.
The function of RAM is to store current running operating system, application programs, and data so they can be quickly reached by the computer's processor. When a program is loaded from the hard disk drive, the program instructions are copied into RAM.

Explain what happens when there is not enough RAM to store all of the required data.
When the RAM is full, the least used/oldest page  (data) will be swapped out, by the operating system, to a file on the hard drive disk - Virtual Memory -. If the page swapped out is needed it is referenced and swapped back for another page.
Explain how inserting more RAM in a computer affects its performance.
Inserting more RAM in a computer affects the overall perforamnce of a computer. The speed of operating the copmuter will increase meaning a better quality of use; faster programes. The spped increases as more RAM allows programe instructions to be loaded quicker without swapping out data onto the hard disk drive becuase of a bigger memory. Also, increasing the RAM can improve multitasking of the computer more programes could be stored in the RAM at once.
 Briefly, more RAM provides;

• A better storage for data, more program instructions
• Programes will run faster, less use of virtual memory
• Allows computer to run multiply of programes - mulittask

Memory - RAM

The term RAM is an acronym.
State what the initials RAM stand for:
Random Access Memory

Explain why this type of memory is 'random access' and how this affects the speed at wich data can be retrieved from it.
RAM is a type of random access memory as you can change any party of the ram in any (random) order and you dont need to start at the first memory place, therefore is quciker so data can doesnt need to travel as far and so recievced at a quicker speed.

What is the main function of RAM in a computer?
The main function of RAM, in a computer, is to store data in the memory. RAM allows you to store read, rewrite, and change data without the need of the first memory location.

In what form is data saved in RAM?
Data in the RAM is saved as Binary.

How much data can be saved in each memory location?
1 byte or 8 bits or data can be saved in each memory location

The main RAM in a computer is made up of dynamic RAM or DRAM.

 - Why is it referred to as dynamic?
It is refered to as dynamic because it is memory that has to be constantly refreshed or it will lose its contents (-data it is storing)   
List the differences between dynamic RAM and static RAM

• Static RAM does not need to be refreshed, Dynamic RAM does
• Therefore; Static RAM is quicker as it has no need to refresh and so supplys data to the CPU more rapidly
• Therefore; because of its benefits, Static RAM is more expensive

                                              

 

Group 11 - Home Server

Storage Devices

STORAGE DEVICE - any device used to store data

 

Data is stored as a named file on anytime time of staorage device

Computing devices avaliable in todays market:

 

Mobile Phone Storage 

Flash memory micro chip 

Tablet Computer storage 

Expand the performance of your tablet storage with a micro card to enjoy faster data retrieval and seamless media playback (high-speed microSDHC cards)

 

Smartphone Storage

Expand the capacity of a smartphone with a micro card to bring more favorite apps and mobile media wherever you go. (microSDHC™)

 

MP3 Player Storage

Expand music library and carry thousands of more songs on MP3 players with a microSD card slot using the expansive storage space of a micro card(microSDHC card)

Device	Capacity	Speed of access	Portable?	Durable?
USB Memory Stick	up to 512 GB	Fast	Yes	Yes
HDD - Hard Disk Drive	up to 3TB	Slow(er)	Yes/No	Yes
CD	700MB	Fast	Yes	No
DVD	8.5GB	Slow	Yes	No
Memory Card	512MB		Yes	Yes
SSD - Solid State Drive		Fast	Yes	Yes

 

 

 The Cloud Storage Vs Local Storage

The Cloud Storage: anywhere, any time, as long as you have Internet

It has become fixed in how we store, access, and share files, photos, videos, and more. What's not to like? Cloud storage, you can access your file anywhere from any device. They practically act as remote backups, for those cases when you lose, or delete, your local copy.

However, you do require an Internet connection for advance activities. You can edit, view, or do anything else with local copies stored on your device, but you need an Internet connection to upload, sync, and download any file. It's not always a problem but not all locations are created with great internet coverage. Should you have an Internet connection, you still have to be careful of bandwidth usage, downloading large media files all at once may not be appropreate. Although you could stream them but that depends on avaliability of Internet connection.

Another drawback is the question of security and privacy benefits that these cloud services offer. A big issue is the ability of third parties gaining access to your data or use your Internet traffic, with or without the knowledge of service providers. Anything you put out on the Internet; cloud storage, social networking, anything, is always open to theft.

 

Local Storage: fast and secure and fragile

Having the files and work you need right at your fingertips, almost literally, is a huge convenience. An advantage with local Storage compared to Clound storage is you dont have to worry about download or upload times, you are instanly able to watch videos without lag or buffering, also with the ability to listen to your tunes endlessly. To add, there is no need to worry about unwanted eyes and hands gainning access to your data. As long you keep contenet or source off the Internet, you have very little to worry about of the files. The security and privacy of your data is as strong as you allow it.
However you are limited to the amount of data you can store at a single time. The highest capacity of internal storage commonly found on smartphones are capped at 64 GB, the most common high capacity microSD card is 128 GB, but not all smartphones can even support that yet. You can expand your available storage with a useful combination of an external hard drive and a USB on-the-go (OTG) cable but is inconvenient. You end up, trying to decide which files you want to always be with you and files you would swap around with your computer or hard drive. Plus its not an exactly fast or easy way for sharing photos and files with others.

 

Apropriate storage devices 

·         Store a high definition movie -  DVD, BLU-RAY

·         Distribute some software that you’ve written - CD (inc. CD-R, CD-RW), DVD

·         Transfer GCSE Media coursework between home and school - USB Memory stick

·         Storage area on a college network - HDD

 

Factors that should be considered when selecting a suitable storage medium to use in a given situation:

• Capacity
• Speed
• Durability 
• Portability 
• Reliability

An example device that makes use of solid state memory storage would be a Memory Stick or USB Memory Card.

 

One benefit of using a magnetic storage device (a HDD) compared to a solid state device (SSD) for storing files on a network is the capacity, HDD has a much higher capacity than a SDD.

 

 

 

 

 

 

 

 

 

 

 

 

 

Fetch Decode Execute Cycle

Fetch Decode Execute

What does a computer do?

 A computer runs a computer program

What is a Program?

 A program is the sequence of instructions stored in 'memory' required to solve a specified problem.

 

The computer will typically perform the execution cycle when taking on any instruction.

 

There will be different parts :instruction memory, control unit, data memory and data processing / local storage.

 

Three main stages of the cycle include: FETCH -  DECODE -  EXECUTE



 

First, the CU fetches a single instruction and data from the main memory

 

             The instruction is decoded

 

The ALU executes the instruction

 

The ALU sends the result of the processing back to the control unit – this is stored in the memory unit.

 



CPU - Purpose and Functions of the CPU

 In a computer, what covers the microprocessor? Why is it nessasary?
The microprocessor is covered by a heat sink which prevents the risk of over heating the computer's processor after running a number of multiple programes at once. Without a quality heat sink, you could be at high risk of destrying your entire system, costin you hundreds or even thousands of pounds.

 The microprocessor contains integrated circuits that make up the CPU.

CPU =  Computer Prcoessing Unit

Computer Processing Unit is responsible for executing a sequence of instructions known as a program. The program will take inputs from an input device, process the input and output the results to an output device.

 

The CPU is hardware that executes programs and manages the rest of the computer system. It sits underneath the heat sink on the motherboard and is made up of millions of electrical switches called transistors.

 



Most electronic devices rely on CPU's for operation; mobile phones, DVD players and washing machines are examples of equipment that have a CPU.

 

The CPU contain different functions

• The control unit is in charge of processing. It interprets the software instruction and sends the right data and operation to the ALU. It accepts the result of the processing from the ALU and sends it back to the memory unit. The CU will keep track of the sequence of instructions and the location of each item of data and software instruction in the memory unit.
• The Arithmetic and Logic unit (ALU) carries out mathematical tasks rapidly, performs calculations and logic operations in binary form 1/0 on data from the memory unit. The ALU transforms the digital data and outputs the resulting value.
• Registers (Memory Unit) store items of data and send them to the ALU for processing. The result of the processing will be copied back to the memory unit for storage

 

 

 

Fetch Execute Cycle: Task 1

Fetch-Execute Cycle:

CPU are the initials that stand for Central Processing Unit

Three main components of the CPU:

• Arithmetic Logic Unit (ALU)
• Control Unit (CU)
• Registers.

In relation to computer architecture, buses transfers data between components inside a computer, or between computers. 

There are different functions in the fetch-execute cycle:

• The Program Counter - incremented by 1 so that it now has the address of the next instruction. Controls the activities of the computer by executing (carrying out)
• The Address Bus - The memoryaddress of the instruction to be fetched istransmited from the program counter to the RAM through the address bus.
• The Data Bus - when the instructon is being executed. Data is transmitted from the RAM back to the instruction register in the CPU through the data bus.
• Decoder - In the countrol unit and works out what the intruction means and what has to be done to the data.
• The Arithmetic and Logic Unit - The control unit instructs the ALU to carry out and execute instructions by performing all the mathematical calculations of the CPU

Computer Ethics: Online Privacy

Online Privacy is  the privacy and security level of personal data & information published via the Internet. It is used to protect a number of things; sensitive and private data, communications, and preferences.

Online privacy is vital to computer users and a current cause of concern for anyone planning; an online purchase, visit a social networking site, participate in online games or attend forums.
Privacy violations and threat risks are standard considerations for any website under development.

What are the risks?
Online privacy risks include:

- Phishing; A Internet hacking activity used to steal secure user data, including username, password, bank account number, security PIN or credit card number.
- Pharming: used to redirect a legitimate website visitor to a different IP address.
                                            
                                                           ... Both are Internet hacking activities
       
- Spyware: An offline application that obtains data without a user's consent. When the computer is online, previously acquired data is sent to the spyware source.
- Malware: An application used to illegally damage online and offline computer users through Trojans, viruses and spyware.

Example: If a password is revealed, a victim's identity may be illegally used or stolen.
A Twitter/Facebook user could get their account hacked (illegally) This could lead to sharing of private information, publishing of violent or abusive language etc. Making out as if the user is committing the crime.

How private is your information online? i-Cloud?
i-Cloud is a storage device used by the highest percentage of people around the world. It is seemed to be very convenient however it has been announced by experts that it should not be used for any emails or photos that are wanted to be kept private. For this reason they recommend people change their passwords at least 'once every three months' and when doing financial transactions and to use the Internet through hard wire instead of Wi-fi. With wifi being wireless hackers are more persuaded to violate accounts easily without anyone noticing.

iCloud seems to be as secure as ever, but the safest way to keep sensitive information secret is to not sync it with iCloud or any other online service (social networking sites inc.). If you have “sensitive” pictures you want to keep private, turn off Photo Stream and they won’t be sent to iCloud and will only live on your device. The best form of security is you just like any service, iCloud is only as secure as you help it to be

“Even though someone doesn't know your password, they can reset the password to something they know and once they do that, they’ve got you”

Companies hold information about you it is up to you what you share and give out but once it's given the companies has it forever. They shold have to ask your permission to share your information however in some sercomstances, this is not the case. Companines and networks hold many thousands of data, it is under their control what they do with it.

"You own all of the content and information you post on Facebook, and you can control how it is shared through your privacy and application settings."

Computer Ethics: Freedom of Speech

Freedom of Speech is a persons right to express their opinion and ideas publicly without interference and restrictions from the government. Freedom of Speech is part of the Human Rights Law and is recognised around the world in each political and international Right article.

It is for 'Everyone to have the right to free their opinion and expression' weather that's:
- To hold opinions without interference
- the right to seek information and ideas
- the right to receive information and ideas
- the right to impart information and ideas
                                                                 ... through any media type:
- be it orally
- written
- printed
- via the Internet (social networks)
- through art forms

How free is YOUR speech on the Internet?
Statements have been made that the Internet is found to be a 'free speech zone'. The government have said they can no more restrict a person's access to words or images on the Internet. An example given: ' It's no different than being allowed to snatch a book out of a reader's hands in the library, or to cover a statue in a museum.'

Can I limit access - as a parent?

Many people including parents are truly concerned about what their children can view and access on the Internet. To limit this special programs 'Web filters' can be installed. This will automatically block access to Web sites that are unsuitable for children.
  

- - - Twitters' Story - - -

Twitters idea of Freedom of Speech is to protect their users' right to speak freely and maintain their ability to contest about their private information revealed. Twitter have said they may need to release information required by law, but we try to notify Twitter Users before sharing their information to give them a chance to stop us, if they feel necessary.

 

Prosecution for online behaviour: Federal authorities are involved in prosecuting a variety of computer based crimes.

- Language           - Pictures  

Computer Ethics: Netiquette

Netiquette is a set of rules for web users around world regarding the use of online language and how to behave towards other Internet users.

Common example of rules suggested:

Avoid using capital letters (seen as SHOUTING)

Keep emails short, to the point

Do not insult other people, as this could be saved and forwarded to them

Do not send large attachments without warning, this would fill up their mailbox and stop further mail being delivered

The Copyright Designs & Patents Act

The Copyright Designs & Patents Act gives creators of media rights to control how their music, books, video and software are used and distributed by others.

Limitations of Copyright:
When you buy software, music, books etc the copyright law forbids you from:

• giving a copy to a friend
• making a copy and selling it
• using the software on a network/Web
• renting the software without the permission of the copyright holder (publisher) 

Protection:
The software industry has set up an organisation called FAST to try to prevent users from breaking copyright law. Copyright offenders can be prosecuted and sent to prison if caught. It is a CRIME.

Computer Misuse Act

The computer misuse act deals with misuse of computers and communications systems in several forms. It is designed to protect users from attacks and theft of information. Offences include;
- unauthorised access to computer material
- unauthorised access with Internet to commit or facilitate a crime
- unauthorised modification of computer material
- making, supplying or obtaining anything which can be used in computer misuse offences

Penalty Levels of Computer Misuse Act:
Offence level  -  Penalty
          1            -  up to Six months in prison / hefty fine
          2            -  up to Five year prison sentence / hefty fine
          3            -  up to Five year prison sentence / hefty fine
          3a          -  up to Five year prison sentence / unlimited fine

 

Reliability

Reliability is the quality of being dependable or trustworthy. Reliability is crucial in everyday life, unreliable systems can cause disaster. Reliability is important in all things: systems, banking industries need reliability as they store personal data and information about thousands of people, if they didn't have strong reliability money from banks would be lost, stored images on systems would be lost. All things have reliability, or else we wouldn't be able to save images, travel, communicate or live routine. We depend on phones for communication, alarms, to take and store images that can be viewed many times over. If our phone broke we would have no alarm therefore be late, no communication and all images would be lost.

To improve reliability, all companies and businesses should use hardware and data redundancy. Hardware redundancy is a process of physical back up to do with power, where as data redundancy backs up all data and information, saving files and making the best possible uses of storage.

 - Hardware redundancy would be used in aeroplanes. life and death, There are four engines in a plane if one breaks, the other three will adapt so the plane can still fly.  
- Data redundancy can be the turning on and off of your computer if you continued to do so if would soon beak.

Week One

The first week of OCR Computing began with an introduction to key terms; "what is a computer?" I now know its a device that can input, store, manage and output data, a calculator.
In more depth, I learnt about Binary code and ASCII table. Binary is the code a computer uses to calculate and display letters on the output (e.g a computer screen). To work out binary its simply many 0's and 1's placed into the binary table and added up:

128	64	32	16	8	4	2	1
0	1	1	0	0	0	1	1

To work it out you simply add up all the numbers displayed by 1's;  the above adds to 99 and corresponds to letter C in the ASCII table.

So:
A computer is a device that process, inputs, stores, manage and outputs data.

The Binary table headings are easily remember by simply doubling the amount each time from right to left. 128, 64, 32, 16, 8, 4, 2, 1.

    

Introduction

I am currently studying Compter Science, following the OCR Computing GCSE, which will take two years. I have made this blog and will be using it to post my work, giving updates on what I have learnt each week.