1.1 Hardware and Communication

Test your definitons

Central Processing Unit (CPU)

brain of the computer, that carries out all mathematical and logical operations necessary to execute the provided instruction

Arithmetic Logic Unit (ALU)

Part of the CPU that performs simple calculations. It processes and manipulates data temporarily stored in registers

Control Unit

Part of the CPU that sends and receives signals from all parts of the computer, via the control part. It ensures all instructions take place at the right time and order

Registers

Temporary storage location used to store data and control information

Internal Memory

storage location of the CPU used to store non-urgent data. Data from registers are transferred into the internal memory if not actively used.

Busses

Part of the CPU that allows data to be transferred to and from all parts.

Random Access Memory (RAM)

Component of the computer that stores programs that are being executed or that will be required for immediate use.

Read Only Memory (ROM)

Part of the memory marked as read only. Data cannot be edited nor deleted. (BIOS chip)

Cache

Middle-man between the processor and memory. It is regarded as a shortcut due to its high speed.

Pipelining

Hardware feature that speeds up the execution of instructions

Parallel Processing

a type of multi-core systems, where two or more processors work together to perform tasks.

Name 2 Advantages of Parallel Processing

• More instruction can be executed in a short amount of time

• Cores have less instructions so less errors

Give 2 disadvantages for Parallel Processing

• Difficult to program these systems

• Results need to be combined from all cores

Fetch-Decode-Execute (FDE) Cycle

Data is fetched from main memory and stored in registers. CPU decodes the instruction to make sense of the task. Data processing occurs and the instruction is carried out and stored in the register

Input Device

A device that is sued to introduce data into a computer.

Output device

A device that allows data to leave a computer in a form that is usually useful to users.

Secondary Storage

Locations not directly accessible to the CPU and therefore have a larger memory but slower access speed

Magnetic Devices

High capacity, cheap and slow storage location where data is stored on a magnetic medium. Data is read using a read-head and written using a write-head.

Optical Disk

Storage location that users lasers to manipulate data. Lasers are projected, if reflected data is read as ‘1’ if not data is read as ‘0’.

Solid-State Drive (SSD)

Portable memory cards that have no moving parts, and a low capacity

Defragmentation

Process in which files are physically re-arranged on a disc to improve speed and organisation.

Network

A number of computer interconnected using wired or wireless technology, primarily to communicate and share resources.

Network Topology

Physical layouts of computers in a network.

Bus Topology

All devices are connected to the connection medium (backbone).

Advantages of Bus (3)

• Less cabling

• Cost-effective

• Easy to add nodes

Disadvantages of Bus Network (2)

• Difficult to troubleshoot the bus

• If backbone fails the whole network fails

Star Topology

All devices are connected to a single central device

Advantages of Star topology (2)

• Reliable

• Easy to add node

Disadvantages of Star (2)

• If central device fails, whole network fails.

• Expensive

Ring Topology

each device is connected to other devices to form a ring-like shape

Advantages of Ring (3)

• Less cabling

• Reduced data collisions

• Reliable

Disadvantages of Ring (2)

• If any part of the network fails, the whole network fails

• Difficult to add nodes

Mesh Topology

Each device is connected to every other device

Advantages of Mesh (1)

• If one path fails, data can still be transferred through other paths

Disadvantages of Mesh (3)

• Difficult to add nodes

• Extensive cabling

• Hard to set-up

Protocol

A set of rules governing the way in which data is moved from device to another.

HyperText Transfer Protocol (HTTP)

A set of rules that govern how hypertext and resources are transmitted over the internet

File Transfer Protocol (FTP)

A protocol that governs how files are transferred from device to another, over the internet.

Simple Mail Transfer (SMTP)

Protocol used to send emails from one server to another

Post Office Protocol v3 (POP3)

Protocol allows emails to be received

Internet Message Access Protocol (IMAP)

Protocol used for transferring emails. Allows multiple clients.

Dynamic Host Configuration Protocol (DHCP)

Protocol used for assigning IP address to devices on a network.

User Datagram Protocol (UDP)

Alternative to TCP, used for loss tolerating connections between the applications and internet.

Handshaking

When two computers exchange information and signals in order to set up a communication link after agreeing on a set of protocols to use.

Hub

Allows more than one computer to be connected in a network, by connecting it all to a central device.

Switch

Analyses each data packet and sends the data to the addressed location.

Routers

Connects part of networks together. Could connect two different networks together.

Wireless Interface Card (WIC)

Hardware that allows a device to connect to a wireless network.

Wireless Access Point (WAP)

Allows wireless devices to be connected to a wired network.