Saturday, 4 February 2012

Basic Hardware (Easy)

Basic Hardware explained

A computer is made up of many different components and all have a different role to play in order for the computer to work.
The Motherboard
 The motherboard is the putty that allows the components to connect to each other. Think of the motherboard as a house. You can buy a new sofa for your house and it will fit perfectly, but without the house the sofa would be useless as it would get rained on etc. 

When you are building your own computer, the first component to look for should be the motherboard because the type of motherboard you get will depend on what type of hard drive you can get (IDE/SATA), RAM (DDR2/DDR3) etc.

The GPU (Graphics processing unit)

This is what fuels your monitor. Without a graphics card you would not be able to use a monitor with your computer. Old motherboards have integrated graphics with allow a visual display of the computer. If you want to use the latest games, graphics software or editing software then the integrated graphics will not work.
The CPU (central processing unit or Processor)
This component allows process to occur on your computer. The bigger/better (3Ghz) the processor, the more processes it can handle. This device gets very hot and the computer shouldn't be started without the processor having either a heat sink or a fan above it.

The Hard Disk Drive
This is where all of the information is stored. The operating system is stored here and all of your pictures and videos. Hard drives use magnets to retrieve the data that is written on them.

Depending on the hard drive you get you will find that they spin at different speeds and vary in size (500mb, 1TB, 3TB etc.). When you see a specification of a hard disk drive saying that it spins at 7500rpm it means that is the number of times it spins in revolutions per minute. The faster the HDD spins, the faster information is retrieved from it. 

The RAM
RAM stands for Random Access Memory. It is where the CPU can read, write and access data.
All information stored in RAM is lost when the computer is shutdown.

The Power supply
This provides power for the computer. When building a computer, you have to consider the types of components you are using and their power consumption.
The CD/DVD Drive
The CD/DVD drive is usually located at the top of the computer at the front. Here you can put in disks and the computer will read them.

Expansion card slots
PCI stands for "Peripheral Component Interconnect". On a typical motherboard you will find PCI slots along with PCI-E slots where the "E" stands for express. These slots are faster than the normal PCI slots. They are usually for expansion cards that require faster speeds such as network cards or GPU cards.

North Bridge
The North Bridge is controls communication of all the faster devices on a motherboard e.g. CPU, GPU,PCI-E slots etc. The north bridge closer to the processor than the south bridge.

The South Bridge
This device speeds up and slows down communication speeds of the slower devices on the computer e.g. PCI slots, USB, Front panel, audio etc.



 

Tuesday, 17 January 2012

Hardware (Easy)

Hardware

The Back of a PC


 The photo above is a picture of the back of my old dusty PC. You will find these basic/common ports on most computers.
Look at the numbers in the picture to find out what ports they are.

1. These are PS2 ports. The purple colored port is for keyboards and the green is for mice. You wont find these ports on the latest computers as the keyboard and mouse connect via USB.
2. This port is called a VGA port for VGA cables. VGA cables are what hook up to your monitor and allow you to see an image on your screen. Depending on your computer, your VGA port will be located on your graphics card along with DVI and HDMI unless it is integrated onto the motherboard (most laptops will be integrated)
3. These are USB ports to allow other connections to be made to the computer such as external hard drives, flash drives, cameras etc.
4. This is a RJ45 port or a Ethernet port for an Ethernet cable. Ethernet cables allow connections to other network devices such as a router or another PC.
5. These are the audio ports. You have the mic port and the headphone/stereo


This is the motherboard of my old PC.

1. PCI Slots
2. South Bridge
3. PCI Express Slots
4. North Bridge
5. CPU Fan (on top of the CPU or Processor)
6. RAM Slots (Memory)
7. Back Ports


This is my current PC.

1. Power supply
2. PCI Slots with a network interface card
3. PCI Express card - USB Controller
4. Graphics Card
5. Hard Disk Drive
6. RAM Slots


The top half of my PC.

1. CPU Heat Sink on top of CPU
2. DVD Drive
3. RAM Slots
4. Fans that are part of the case. (total of 4 fans)
5. Back Ports
6. North Bridge.




In my next hardware post, I will explain what the purpose of these components are.
This post should give you some information on the basic structure of a mother board and name some of the major components. There are many different types of components e.g. motherboards, graphic cards, processors etc. if your computer looks nothing like mine then this is why.

Saturday, 14 January 2012

Protocols

Satellite - STP stands for Satellite Transport Protocol. It has a low bandwidth and low connectivity

HTTP - Hypertext transfer protocol is used to communicate with the webpage and request the selected webpage.

IrDA -  Infrared data association is a simplex communication as you aren’t receiving any information back from it. An example of an IrDA protocol would be the one used in remote control. This type of communication needs to have line of sight.

Cellular radio/network - Cellular radio is a simplex communication as radio waves don’t pick up any responses.  This broadcasts a message that most media devices can pick up.

GSM/UMTS - (Global System for Mobile communication) is a standard for describing 2nd generation digital cellular networks (2G).

IEEE WiFi802.11 standards - This is the standard that defines a wireless interface between the clients. This specific wireless standard is used for WLANs (wireless local area network) The IEEE stands for Institute of Electrical and Electronics Engineers.

TCP/IP - Transfer control protocol. This protocol is used for sending and receiving information over the internet. This protocol requires information to be sent back confirming that the first packet was sent and arrived correctly without any corruptions.

Ethernet - Ethernet is a network communication standard and is used to create LANs. They transmit at speeds between 10mb/s and 100mb/s.

Frame Relay - Frame Relay is a protocol standard for local area network. It is used for fast transmitting.
They travel through virtual circuits. This means they take the logical paths from the origination. The frame relay protocol replaces the header of a packet with a 2 bit header and that contains the destination address. Frame relay increase reliability of the communication lines.


ATM -  ATM protocol is used to support voice and data communications at high speeds.
ATM uses the data link layer in the OSI  model. Synchronous and Asynchronous.

Token Ring - Token ring is where the computers are connected in a ring called a LAN.
It is used to stop any collision in the network as all the traffic goes one way. This can be slow for the network.

UDP - UDP stands for User Data protocol. This, like TCP is a transportation protocol except that it doesn’t require a reply/confirmation for the next packet to be sent. This protocol uses less bandwidth than TCP. This protocol is used for online streaming etc. so you can get a smoother running picture instead of having to wait for it to buffer.

Friday, 6 January 2012

Features and Functions of information systems

 The Features and Functions


Information is very important in business because you can see where you can make cuts in people’s jobs if you know the input, output and what’s required


The features of information systems are: data; people; hardware; software and telecommunications.

Data
You need data for it to be processed into information. You need information to make business decisions. An example from the insignia scenario would be ideas from the client go to the design team and they process that to come up with a mock up of what the final project will look like. If the client wants to change the look or is not happy with it the process is repeated until the end user is happy with their product


People
People are the process. Everyone has different ways of turning data into information unless they all have the same variable e.g. the number 2004 means different things to different people because they process it differently. People manage the data and without people you would not be able to input process data and get any output back into the business.
Insignia rely on people to get the data from their clients

Hardware
Hardware are the tools that you use to collect and use the information. These are the physical components. These need software to be able to get the job done.       


Software
Software could and is everything. Your brain is software because it tells your body (hardware) what to do. You need a human to collect the data and someone else to process it into information.

Telecommunications
Telecommunication is data, people, hardware and software communicating together. If they did not communicate the business would loose money and you would not be able to get accurate data. E.g. software and hardware needs each other in order to be able to work, if they do not communicate the data could not be processed by the people.


The functions of information systems can be broken down into: input; storage; processing; output; control and closed and open systems.


Input
Input is the data that you collect this data can be anything but it will not mean anything to anybody until it is processed. If processed in different ways it will mean different things to different people.

Storage
The storage of information has to be secure especially if the information is about people then it falls under the data protection act. The storage has to keep the information safe but has to be accessible whenever the organization needs the information so easy access is essential.

Processing
This is where the data gets turned into information so that you can understand it. Data can be processed in different ways such as the number 2010 will mean the year to some people and just a number to others.


Output
Output is what you get out of something.
If you are spending money on input but not getting any output it is not cost efficient.
E.g. spending £500 on research that will only save you £200 in the future.
Output can be different things such as money or feedback about your business.
If you know the input and output of someone’s job you can see if what they do is a value for money. If it isn’t the business should get rid of it. Output comes from processed data.

Control
This manages the behavior of other systems and produce a desired output.
It controls a lot of the business. Its process is check, record, regulate, supervise, authenticate. It is a good management technique.



Feedback loops
Insignia at the moment use this information technique. They get the design off of the client, improve it, run it by the client and make any changes to suit the client’s tastes. They do this process until the client is happy with their end product.
This is a good process to do because you give the client exactly what they want instead of making something that they didn’t.



Closed and open systems
Closed systems means that the business has a internal relationship E.g. they don’t talk about their profits or looses for the past year.
An open system shares its information with the outside world allowing them to look at their profits and/or losses. Both systems have their advantages closed; you are not giving any information away to competitive businesses, Open; letting other people see your profits could create new business opportunities



Types of information systems



Management information systems
This system follows steps and plans a time schedule for the work that needs to be done. They allow the ability to collect vast amount of data for a business.
This system allows for employees to be monitored so managers can see if any cuts to save money can be made.

Marketing (sales performance, competitors)
This information system technique allows it to analyze marketing information. It gathers information all the time from sources inside and outside the business. E.g. from suppliers and from managers. This allows businesses to make decisions based on that information.


Financial
This system is designed to meet the businesses financial obligations as they come near. It is designed to manage everything financial. It will keep a good margin of profit and pay the minimum expenses it can.



Human resources
This manages workers payrolls, work time, benefits, HR management information system, recruiting, training, performance record, employee self service.
This reduces the workload of the management.

Monday, 2 January 2012

Characteristics of good information

Good information

Accurate

Information has to be accurate in order for it to be valid.
The information wouldn’t be any good to anybody if it wasn’t.
You wouldn’t be able to make decisions based on that information. More
Accurate information means more accurate decisions made.

 Relevant 
 The information has to be relevant. If you want to find out information on a    business’s work force and you are told about their suppliers it won’t be helpful. This issue
 Of your researchers knowing what information to collect so communication is also vital.

Up to date
Information isn’t any good if it isn’t up to date. This is very important so businesses can keep on top of information so they can make decisions and plan their business.

 Timely
 Information is a waste if you get the information a week after you wanted it so you                          
can’t do anything with the information. If you need information by 5:00 and you get it at 9:00 the information is useless and you can’t use it. Information has to be accurate and quick in order to be useful.

Cost efficient
If the research to get the information costs more than you will save with the information then it isn’t worth it. It isn’t a good business plan if you do this.

Reliable
Information has to come from a source that can be trusted or if not then should be cross checked to see if information is true. If the information is not reliable then using it to decide business decisions is a very bad idea.

Accessible
Information has to be accessible. The information is no good to you if you can’t see it. You can’t make decisions based on information that you can’t read. If a report you need is in another country it will not be any good to you to make any decisions.

Wednesday, 28 December 2011

Converting IPv4 addresses into Binary (Hard)

What is Binary?


Binary is the language that the computer speaks in and it consists of zero's and one's e.g. 110100101101.



Without a protocol, these numbers would mean nothing. You need to tell the computer how to read the numbers e.g. 1010101111010 could mean nothing if the computer read it as text but a butterfly if read as a picture.





Converting Binary into an IP4 and vise versa.

A IP4 address is made up of 32 bits (4 bytes) and consists of 4 sets of numbers that are 8 bits each (one digit is one bit - 11010010 = 8 bits/1 byte).

An IP address = 192.168.1.1 which would look something like 11001100.10100101.01101010.00101101 in binary.

The biggest IP address you can get is 255.255.255.255

To convert an IP into binary, you simply use the 8 numbers below to add up to the byte you want to convert.

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

e.g.

 192.168.1.1

192.

128 goes into 192, so we put a 1. We are now left with 64.
then we go to the next number along which is a 64.
64 - 64 = 0 so we put a 1.
We have now reached 192 by adding the first 2 numbers together.
Our conversion should look like this - 11000000.

11000000 = 192.

128.64.32.16.8.4.2.1
1     1   0   0   0 0 0 0

And to convert it back you do the reverse.

This is quite hard to understand, especially because i am writing it down.

As always, if you have any questions please comment and i will answer you.


Tuesday, 27 December 2011

Factors that influence webstie performance.

 Some Factors that influence website performance.
 
These are some factors that have to be taken into consideration when wanting to improve/create a connection or site. 
 
Clients side (your machine) - 

Bandwidth/quality of connection - the connection speed you have to the internet is going to be a huge factor in the time it takes to load webpages.
distance from the exchange - the further the distance the lower the connection quality as the request has to travel further.
Browser - some browsers are much faster than others (some are built for speed and some are built for utility)
Cache - some browser's caches are better than others (cache remembers graphics/text on a website so it doesnt have to be downloaded again)
PC performance - RAM, processor power etc. The better hardware you have the faster the requests can be sent to the webserver and the faster they can be recieved.
Anti virus software can slow down if the site has to be scanned before hand.
network interface card - the better (bigger bandwidth it can hold) N.I.C is the faster the connection will be.
Wireless - is there any interferance from anyother wireless devices and how far away from the router is the computer.
Wired cables - is there any interferance to the cabling (ethernet, UTP)


Server side - 

Number of clients accessing that site at any given time - The more people you have trying to access your website the more slower the site will become (this factor depends on how much bandwidth/traffic your shared/dedicated web host has to use.
DOS attacks - denial of service attacks are where someone requests a lot of information from the web server that the website cant handle so it goes down and noone else can use it 
Amount of content/media and the size e.g. a page with hundreds of images on it will load slower than one with just text.
Quality of the code (HTML, CSS) - The speed can be increased if the code is well written.
Qualtiy of server software - The server software could slow down the site.
If the web server is shared or dedicated. If the server is shared then you are sharing web space with other websites so your bandwidth will be limited whereas if your site is being hosted on a dedicated server then it has as much bandwith as that server can provide.
Web server hardware - the speed of the server RAM, processor is like the computer. The faster they are, the faster the clients webpage requests will be answered.