A+ TRAINING - Tulsa Technology Center

Instructor - David Williams

[email protected]

January, 2000

Brian Jenkins

These notes were compiled from class notes, Element K class books, and the Sybex 1998 A+ Study Guide (by David Groth).

BREAKDOWN

CPU's or chips were initially DIP (Dual In-Line Package - pins were arranged in a row along the 2 long sides of a rectangular chip), now are PGA (Pin Grid Array) format in which the chip is square and has pins along 4 sides underneath the chip (Zero Insertion Force = ZIF)

• CPU's contain sets of instructions designed to complete tasks
• Each task is included in the commands of the chip
• Intel chips hold many commands, Motorola chips hold few commands (which resembles more speed in the processing, but in actuality the processor simply has fewer tasks to perform and so functions with more efficiency

Motorola (RISC - Reduced Instruction Set Chip)

• 68000 - 1979 - 32 bit address bus, 16 bit data bus
• 68010 - 1982 - included virtual memory support, 3 instruction cache (subroutines react faster with this configuration)
• 68020 - 1984 - 32 bit data bus introduced, allowed floating points, 4 Gb RAM
• 68030 - 1987 - demand paged memory
• 68040 - 1989 - Increased speed of processor

Intel History

Math Coprocessor: Improves the processor's number crunching speed - for complex calculations.

Clock Speed: Frequency with which a processor executes instructions. It is measured in millions of cycles per second (Mhz).

Data Bus: Used to send and receive data. The larger the width, the more information can be transferred at once, and therefore the faster the bus.

Address Bus: Also communications with the processor, but describes the memory locations of data.

Internal and External bus: Also known as the System Bus, or the Expansion Bus - allows the processor to talk to another device. It is called external since it operates outside the processor. Devices are connected through Expansion Cards.

Other Processors
1. AMD
2. Cyrix
3. Athlon

Binary Counting

• 2-0 = 1 bit
• 2-1 = 2 bits
• 2-2 = 4
• 2-3 = 8
• 2-4 = 16
• 2-5 = 32
• 2-6 = 64
• 2-7 = 128
• 2-8 = 256 bits (byte)
• 2-9 = 512
• 2-10 = 1,024 bytes (Kilobyte)
• 2-11 = 2,048
• 2-12 = 4,096
• 2-13 = 8,192
• 2-14 = 16,384
• 2-15 = 32,768
• 2-16 = 65,536
• 2-17 = 131,072
• 2-18 = 262,144
• 2-19 = 524,288
• 2-20 = 1,048,576 bytes (Megabyte)
• 2-30 = 1,073,741,824 bytes (Gigabyte)
• 2-40 = 1,099,511,627,776 bytes (Terabyte)

Important Levels of Memory

Electricity

Structure of a Hard Disk

• Sector
• Cylinder
• Platters
• Laser
• Heads

The inside of a Hard Drive. A view of Tracks and Sectors. With multiple platters, the "stacked sectors" make up "cylinders."

IRQ's

• 0 = System Timer
• 1 = Keyboard
• 2 = Cascade (connected to 9)
• 3 = Com 2 & 4
• 4 = Com 1 & 3
• 5 = LPT2
• 6 = Floppy
• 7 = LPT1
• 8 = Real Time Clock
• 9 = Cascade (connected to 2)
• 10 = Available (Sound card)
• 11 = Available (NIC)
• 12 = Mouse
• 13 = Math Coprocessor
• 14 = HD Controller
• 15 = Available

Cables

• Serial - data sent in a single string, one piece at a time, longer cables, but slower originally
• Parallel - data sent in groups simultaneously - shorter cable, but have faster connections

Memory

Physical Memory - Integrated Circuits that are electrically charged and store data in binary fragments called bits represented by the numbers 0 and 1. There are different types of memory:

SRAM (Static Random Access Memory) - the data doesn't need a constant update or refresh, can generally only store 256K bits per integrated circuit.

DRAM (Dynamic Random Access Memory) - rather than using 0's and 1's the data is stored as charges in very small capacitors, needs a constant refresh signal to hold the information, can hold very high amounts of info.

EDO RAM (Extended Data Out) - eliminates memory "wait states" to improve performance by 10%, but more expensive.

ROM

PROM

EPROM

EEPROM

Memory Chip Types

DIP (Dual Inline Package) -

SIMM (Single Inline Memory Module) -

Specialized Memory Types

Video RAM -

Windows RAM (WRAM) -

Portable Memory -

Cache Memory -

Additionally the following forms of memory appeared:
• EMA
• XMA

TCP/IP Communication

• Modems (Modulator / Demodulator)
• Changes binary (digital) data to analog and transfers it over a phone line to another modem, which then demodulates the data (analog to binary or digital), and sends it to the receiving processor to further interpret the data. Modems are limited to maximum speed of 56K, and use asynchronous methods of communication (see below), which is very inefficient.

• Asynchronous: Start Bit || 8 Bits || Stop bit || Parity bit (11 bits total to send 8)
• Synchronous: Uses clock signal and data signal to synchronize data transfer - good for moving large amounts of data, but clock signal always "on" using bandwidth

TYPES OF NETWORKS

Main Frame
• MF
• DT
• DT DT
• DT DT DT
• DT DT DT DT

Main Frame feeds Individual Terminals (DT = Dumb Terminal)

PC / Internet
• PC PC PC PC
• PC PC PC PC
• PC PC PC PC
• PC PC PC PC
• PC PC PC PC

Internet makes all PC's equal and no single pc is in control (PC = Personal Computer)

Department of Defense Used These Universities to Set Up Internet

1. Stanford
2. Utah
3. Santa Barbara
4. Berkeley

DOD - 4 Layer Model for Internet (doesn't include hardware in this model)

1. Process / Application
2. Host
3. Internet
4. Network

OSI - 7 layer Model

1. Application - Browser, FTP Client etc.
2. Presentation - OS, Shell
3. Session - Client for MSN, establishes connection, redirecter
4. Transpond - TCP/IP language
5. Network - Connects PC's
6. Data - Bits, packets (based on requirements of 7)
7. Physical - Hardware

Troubleshoot from Physical (bottom) to Application (top)

Use device manager to find hardware issues

Next check network layer (winipcfg) - ping local host or 127.0.0.1 - success means bottom three layers are working properly (OSI model)

WINDOWS 9X

Boot Sequence of Windows 9x

1. BIOS - CMOS (checks hardware)
2. POST (Power On Self Test)
3. MBR (0 / 0 sector) - Microsoft Boot Sequence (takes over here)
4. Real Mode (16 bit) - IO.SYS
5. MSDOS.SYS
6. (Config.sys)
7. Command.com
8. (Autoexec.bat)
9. System.ini
10. Win.ini
11. Hardware check
12. Win.com - Enhanced Mode (32 bit)
13. KRNL386.EXE (uses kernel32.dll and kernel16.dll)
14. GDI.EXE (uses gdi32.dll and gdi16.dll)
15. USER.EXE (uses user32.dll and user16.dll)
16. Registry (user.dat and system.dat)

Virtual Memory Manager

IPF (Invalid Page Fault)

page = 16K chunk of information - if there is an error transferring that information from one place to another it manifests in the form of an ipf in module blah blah blah...

Core of Win 9x (6 files)

1. krnl386.exe uses kernel32.dll and kernel16.dll
2. user.exe uses user32.dll and user16.dll
3. gdi.exe uses gdi32.dll and gdi16.dll

"Thunk" - backwards compatibility - 32 bit OS running a 16 bit Application must first "interpret" the file through the 16 bit dll, then execute the command.

Registry (9x and NT)

• user.dat - hkey_current_user
• system.dat - hkey_local_machine

WINDOWS NT 4

Clients - Windows 9X (replaces MS-DOS, Windows 3.x, Win for Workgroups 3.x)

Workstations - Windows NT Workstations

Servers - Windows NT Server

BOOT SEQUENCE FOR WINDOWS NT

1. BIOS - CMOS
2. MBR
3. NTLDR
4. BOOT.INI
5. NTDETECT.COM
6. NTOSKRNL.EXE (specific to each hardware configuration or system)

3, 4, 5 are Boot Disk

Boot.ini looks at this:

• Multi (or SCSI)
• 0 = adapter that controls the HD or first adapter in system
• Disk (0) = bootable disk
• Which is the bootable disk?
• Where is the partition that holds further boot information?

NTFS

• Normal File properties: Read Only, Hidden, Archive, System
• NTFS = extended properties beyond DOS
• SMP - symmetric multi-processing (balanced)
• ASMP - asymmetric multi-processing (not balanced - one processor per task)

Networking

Compare charts of support and compatibility for different OS's (all charts on CD's provided in books by instructor)

Object Based Security

• Everything is an object
• Objects have attributes which define them
• Change attributes to change objects and / or protect them through security and restricting access to only a few.

NT Installation

• 3 floppies hold initial bootup sequence
• FDISK - partitions and formats for NTFS
• NTFS - NT File Structure (System)
• Boot Procedure - loads then initializes OS

Service Packs (learn the details of each)

NT Registry

regedit - normail registry editor, can find things easier, can search entire tree

regedt32 - nt registry editor, different interface - can configure security better than regedit

refine regedit searches by using the keys, value, data designations

File Associations

1. direct through registry
2. shift + right click > open with

Know Requirements for the following

1. DOS (boot disk contents)
2. Windows 3.1
3. Windows for Workgroups 3.1
4. Windows 95 (A, B, C)
5. Windows 98 (SE)
6. Windows ME
7. Windows NT (SP 1, 2, 3, 4, 5, 6)
8. Windows 2000

Find out the following:

If one PC has two ISP's installed, and both dial the same UUNet number to get access to the internet, why can one connect and one consistently fail to connect even though both get a good handshake?

1. MSN + dialer
2. PPC + dialer
3. DUN = dialers identical (or use same dialer and get same issue)
4. Dial ISP
5. Why does MSN connect to UUNet?
6. Why doesn't PPC connect to UUNet?
7. What is in the handshake that identifies the caller to the remote modem, and lets the receiving modem know to which server to send the caller after the handshake?

REGISTRY

3 ways to edit registry in NT4

1. hkey_local_machine - 2 sub keys mirrored outside itself...
2. classes_root
3. current_config

1. regedit or regedt32
2. control panel (most common way)
3. policy editor (defines working environment of pc)

Profiles

1. windows interface
2. user oriented
3. voluntary

Policies

• requirement or restriction
• by default or defined by sys admin

Policy Editor

c:\windows\system32\poledit.exe - allows policies or parameters to be set outside regedit - using poledit controls syntax so typos won't occur in regedit - policies are applied in sequence - in conflicts the last policy applied will be the one that is used

NOTE: (add "$" to a shared resource and it makes it invisible...)

USER POLICY - overrides group policies - is there a user policy? yes - then apply and go to registry

GROUP POLICY - used for workgroups instead of individuals - is there a group policy? yes - apply in group order and go to registry

• gray box - won't change previous settings (off)
• white box - has that setting (on)
• checked box - depends on syntax of command (pos or neg)

Architectural Overview of NT4

(Know user vs. kernel for test)

User mode (things the operator does) vs. Kernel mode (what the OS does)
• Apps and subsystems run in user mode
• microkernel - allows changes to be made to system (can change while running as it loads or unloads drivers)
• monolithic kernel - one size fits all (like win 98) can be copied from one pc to another to fix the kernel problems... NT4 can't do this, as the kernel is specific to each pc

HAL - hardware abstraction layer

Virtual Memory

• RAM - gets highest priority
• Page file - gets next lower priority
• Virtual Memory - lowest priority data

NT 4 Troubleshooting

Performance Monitor - looks at system to help with troubleshooting - (Admin Tools - Performance Monitor)

Windows NT Diagnostics = Start > Programs > Administration Tools > Win NT Diagnostics (much like Device Manger)

1. Computer field - name of pc (network can view other pcs)
2. Object field -
   • Processor
   • Memory (page faults per second and pages per sec)
   • Physical Disk - avg disk queue length

Creating and Using an Emergency Repair Disk

98 boot disk - nearly automatic

NT4 = boot.ini, ntldr, ntdetect > to be used only with the NT4 CD

Sequence

1. get a formatted diskette and insert it into drive a:
2. start > run > "rdisk /s" (repair disk plus update sys files)
3. create rdisk whenever you update drivers etc... any changes to hardware config should be followed with rdisk...
4. repair procedure > choose repair when booting from floppies, it will prompt for repair disk later but needs to know this is a repair at the beginning, inspects registry files, inspects startup env., verifies win nt sys files, inspects boot sector, then asks for disk 3... loads drivers, etc. then later asks for repair disk and cd rom of win nt 4 to finish repairs.
5. repair options (space bar selects)
6. system configuration
7. software information
8. default user profile (ntuser.dat)
9. security policy and sam (user accounts database)

Peripheral Devices

• keyboard
• mouse (5 pin din, 6 pin mini-din)
• monitor-keyboard, mouth-mouse etc. (accesibility)
• trackball
• track pad
• scanner
• printer

MONITORS

• head set monitors...
• interlaced vs. non interlaced - non interlaced is better
• pages 232 - 233 --- learn the monitor and color tables
• degauss = removes the magnetic fields that build up over time in the monitor

How Laser Printers Work (goes through the following steps)

• Clean - rubber shoe - California
• Charge - -600V DC - Cows
• Write - Laser (charge reduced to -100V) - Won't
• Develop - toner on drum - Dance
• Transfer - to paper - The
• Fuse - heats toner, melts to paper - Fandango

Know the other types of printers also:

• laser
• inkjet
• daisy wheel
• dot matrix

Portable Computing

Size and portability are the important points in portable computing

• Notebook, Sub-Notebook = two main classifications
• Processor - uses less power, dissipates heat via mobo rather than fan (no space for fan)
• Storage - Hard drives - typically smaller, but size is growing every day...
• Memory - RAM, harder to install, usually more expensive

PCMCIA CARDS

• Type 1 - Memory
• Type 2 - NIC, Modem
• Type 3 - CD ROMs, Hard Disk drives

Batteries

• NiCad - Nickel Cadmium -
• NiMN - Nickel Metal-Hydride -
• Li-Ion - Lithium -
• Lithium Polymer -
• Zinc Air -

BATTERY STATES

• S0 - fully operational
• S1 - sleep - processor and bus clocks shut down
• S2 - deeper sleep - processor and cache lost from power off to them
• S3 - much deeper sleep - processor and some chips lose power
• S4 - hibernate - power to devices off - must power up everything
• S5 - power off

Screen/Monitor

• Active Matrix vs. Passive Matrix
• Passive = grid gets drawn (rows of pixels can go out in the grid...)
• Active = backlit pixels

NETWORKING

OSI Communication Model (expanded)

PROTOCOL - procedure for accurate information - exist in each of the above layers

NETWORK TOPOLOGIES

• Star topology: organized around a hub,
• Bus Topology: in straight line
• Token Ring: (mau - media access unit) more reliable under a heavy load - controls who sends and receives, data moves in circular motion around network allowing the terminal with the "token" to "speak"
• Polling: mainly in mainframe env. using dumb terminals - will choose who "speaks" and for how long...

Windows 2000

1. Server
2. Advanced Server
3. Professional

features include - see page 247, software manual.

Domain vs. Workgroup

Domain

1. Central
2. Large networks
3. Sophisticated
4. Server required

Workgroup

1. Decentralized
2. 1-10 users
3. Complicated
4. No server requirement

2000 vs. NT

Device Manager is present in 2000, but in NT it appears as WinNT Diagnostics in Administration Tools.

MMC at the command line will bring up management tool.

Hardware installation, right click My Comp > Properties > Hardware > Hardware Wizard.

Registry - "regedit" or "regedt32" brings up registry editor.

spanned: any corruption eliminates all spanned volumes...

RAID Level 0: striping: 2-32 drives: alternates writing between drives...

RAID Level 1: mirror: backs up data as it writes to the hard drive

RAID Level 5: striping with parity: 3-32 drives: if one drive crashes, the data and parity can rebuild the lost information

Linux

Unix running on a PC, PowerPC, I386 etc.

386 with 4 Mb or RAM minimum, with HD of 350 Mb or less... Can be used as a server of any type, can be used as a client with many functions, full sys user capabilities (user id's, security, etc.)

1. reliable
2. low end hardware requirements
3. free, no copyright probs...
4. open source
5. GPL (Gnu Public License - GNU = Gnu Not Unix) - copyleft: everything you CAN do!