Tech Level Cyber Security 2j, 2k, 2l, 2m

Learning Objectives Learners will have the opportunity to: identify and describe computer ports and their purpose including: explain the features of a BIOS and the purpose it fulfils including: universal serial bus (USB) Firewire independent of operating system serial advanced technology attachment (SATA) instructions parallel booting audio input/output identification of devices CPU high-definition multimedia I memory interface (HDMI) power-on self-test (POST). video graphics array (VGA) describe the features of an extensible firmware interface (EFI) and its role in a computer system digital visual interface (DVI) describe the role and purpose of internal and external computer buses including: identify and describe a range of input/output controllers systems bus identify a range of expansion cards and describe the purpose of each (eg sound, graphics, network cards) data bus memory bus parallel bus serial bus.

Assessment outcomes 2j – Basic Input Output System (BIOS) and Extensible Firmware Interface (EFI) and their purpose 2k – Input/Output controllers and expansion cards such as sound, graphics, network cards etc. and their purpose 2l – Computer Ports and their purpose 2m – Internal and External computer buses

Pre-reading discussion The purpose and features of BIOS: Instructions Booting Identifying devices CPU Memory The features of an Extensible Firmware Interface (EFI) Input and Output Devices and Controllers Expansion Cards Computer Ports

Basic Input Output System (BIOS) When you power up a computer, a little program of instructions (known as the BIOS or Basic Input Output System and which is held in the ROM chip) starts running. The job of the BIOS is to check to see if the computer has the basic, error-free hardware needed to get the PC up and running. It runs what is known as a POST routine, or ‘Power On Self Test’. Specifically, this small program checks to see if there is a keyboard, a hard disk, a floppy disk and some memory (RAM). If it finds any of these absent or if it finds an error with any of them, then it displays an error message (and beeps)! Once the basic hardware check is complete, the BIOS then looks in some pre-set places for a special program called the ‘bootstrap program’. Often, the first place it looks in is in the first sector (known as the 'boot sector') of the hard drive and then if it can't find the bootstrap there, it looks in the first sector of any floppy disk in the floppy disk drive or possibly the CD drive.  When the BIOS has located the bootstrap program, wherever it is, it loads it into RAM and runs. The bootstrap program then takes over control of loading whatever operating system you are using. It first of all locates the operating system on the hard drive and then transfers it from the hard disk into RAM and runs it. Once your operating system has loaded, the computer automatically looks for ‘boot files’. These are special files that the user can play with to set up the computer in exactly the way that the user wants. https://neosmart.net/wiki/mbr-boot-process/

Extensible Firmware Interface Unified Extensible Firmware Interface (UEFI) is a specification for a software program that connects a computer's firmware to its operating system (OS). Like BIOS, UEFI is installed at the time of manufacturing and is the first program that runs when a computer is turned on. It checks to see what hardware components the computing device has, wakes the components up and hands them over to the operating system. The new specification addresses several limitations of BIOS, including restrictions on hard disk partition size and the amount of time BIOS takes to perform its tasks. Because UEFI is programmable, original equipment manufacturer (OEM) developers can add applications and drivers, allowing UEFI to function as a lightweight operating system.  https://blogs.msdn.microsoft.com/b8/2011/09/22/protecting-the-pre-os-environment-with-uefi/

Difference between BIOS and EFI Larger Boot Partition BIOS uses the Master Boot Record (MBR) to save information about the hard drive data while UEFI uses the GUID partition table (GPT). The major difference between the two is that MBR uses 32-bit entries in its table which limits the total physical partitons to only 4. Each partition can only be a maximum of 2TB in size, while GPT uses 64-bit entries in its table which dramatically extends the support for size possibilities of the hard drive to 8TB!! Speed and Performance Since UEFI is platform independent, it may be able to enhance the boot time and speed of the computer. This is especially the case when you have large hard drives installed in your computer. This enhancement depends upon how UEFI is configured to run. UEFI can perform better while initializing the hardware devices. Normally this speed enhancement is a fraction of the total boot time, so you will not see a huge difference in overall boot time. Developers can make use of UEFI shell environment which can execute command from other UEFI apps optimizing the performance of the system further. Security Secure boot is a feature of UEFI that has been implemented in Windows 8 recently. The biggest benefit of UEFI is its security over BIOS. UEFI can allow only authentic drivers and services to load at boot time, making sure that no malware can be loaded at computer startup. Microsoft implemented this feature to counter piracy issues in Windows, while Mac has been using UEFI for quite some time now. Secure Boot works by requiring a digital signature of boot loaders which should require digital signature by the Kernel. This process continues until the operating system is completely started. This secure boot feature is also one of the reason why it is more difficult to install another operating system on a Windows machine. https://www.maketecheasier.com/differences-between-uefi-and-bios/ http://techpp.com/2013/12/19/uefi-vs-bios/

Input and Output controllers Alternatively referred to as an input/output interface, IOC, or PIOC for Peripheral input/output controller. The input/output controller is a device that interfaces between an input or output device and the computer or hardware device. The input/output controller on a computer is commonly located on the motherboard. However, an I/O controller can also be an internal add-on that can either be used as a replacement or to allow for additional input or output devices for the computer. This means and IO Controller: Is what an input / output device are connected to It tells the computer how to process input information It tells the computer how to output information to output devices It is usually attached to the motherboard It can also be added to the computer using an expansion card http://www.computerhope.com/jargon/i/iocont.htm

Computer Ports What is a Port? A port is a physical docking point using which an external device can be connected to the computer. – IE a USB Port It can also be programmatic docking point through which information flows from a program to computer or over the internet. – IE an Ethernet Port

Computer ports USB Firewire SATA Parallel Audio I/O (3.5mm) High Definition Multimedia Interface (HDMI) Video Graphics Array (VGA) Digital Visual Interface (DVI)

Internal and external computer buses The address bus. This bus, in black on the diagram, is usually a set of wires that links the CPU to the RAM (and to other places). If the CPU want to fetch an instruction from a particular address in RAM, or wants to write a piece of data to a particular address in RAM, it puts the address on the address bus. The data bus. The dotted channels you can see in the diagram is the data bus. The CPU puts data it wants to transfer to RAM on this bus. If data is being fetched from RAM, then it is put on this bus as well. The control bus. Signals need to be sent around the computer to control when things happen. These signals are sent along the control bus. Tthe striped channel you can see in the diagram is the control bus. http://theteacher.info/index.php/f451-fundamentals/3-1-4-hardware/notes/99-busses

Research task Create a revision poster for one of the following topics – I will share these with the class Internal and external System Buses: systems bus data bus memory bus parallel bus serial bus. Computer Ports and Input Output Controllers BIOS and UEFI Use colour and examples to make your revision poster look more interesting and contain better information!

Crib sheets Using your notes, lesson resources, and the above slides create Crib sheets that you can use to revise the following topics: 2j – Basic Input Output System (BIOS) and Extensible Firmware Interface (EFI) and their purpose 2k – Input/Output controllers and expansion cards such as sound, graphics, network cards etc. and their purpose 2l – Computer Ports and their purpose 2m – Internal and External computer buses

Graded Exercises Complete the graded exercises for today’s lesson. (Lesson 5 Folder) If you have answered a question in your notes circle the section and write the question above it in a different coloured pen.

Pre-Reading for Lesson 6 Topics Resources Input Devices Output Devices Biometric Devices Secondary Storage See the Lesson 6 Folder.