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Virtualization—NETWORKING ESSENTIALS—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
VIRTUALIZATION Understanding Virtualization Virtual machines are self-contained computers running within a host OS Hypervisors support multiple VMs A type 1 hypervisor runs directly on top of the hardware as an OS A type 2 hypervisor runs as an app in an existing OS Your First Virtual Machine Setting up a new VM takes a few steps. Install a hypervisor, like Oracle VirtualBox. Create a virtual machine in the hypervisor. Download & install an operating system, like Ubuntu Linux. Advanced VIrtualization You can modify virtual hardware easily, such as add a “drive”. Bridge a VM to connect to same network (and DHCP server) as host OS. Use NAT to put a…
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Internet & The Cloud—NETWORKING ESSENTIALS—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
Internet & The Cloud The Internet Beyond the LAN Local Area Network (LAN) computers share the same network ID. A wide area network (WAN) is two or more LANs interconnected by one or more routers A metropolitan area network (MAN) is a WAN that spans a city. A personal area network (PAN) is a point-to-point connection used only in Bluetooth connections LAN—computers hooked together to one switch (All share identical Network ID) WAN—bunch of LANs interconnected with routers. Each LAN has a unique network ID. CAN—Campus Area Network MAN—Metropolitan Area Network WLAN—Wireless Local Area Network Intranet—private network Internet Tiers The Internet is composed of many organizations that connect to each…
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Wireless Networking—NETWORKING ESSENTIALS—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
Wireless Networking Wireless Network Hardware A wireless access point (WAP) bridges 802.11 and Ethernet networks Wireless clients connect to WAPs 802.11 works in one of two modes: infrastructure mode, or ad hoc mode Use correct antenna for the job In many of today’s laptops the antenna is built into the laptops monitor itself. (SSID)-Service Set Identifier (SSID) Wi-Fi Standards 802.11 uses the 2.4- and 5-GHz ISM band 802.11 uses remade channels Memorize the band usage and relative speeds of the 802.11 extensions. (ISM) Industrial, Scientific, and Medical Radios Bands 2.4 GHz and 5 GHz Band Band is a range of radio frequencies 2.4 GHz Band: 2.412-2.4884 GHz Uses different “channels”…
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Physical Networking—NETWORKING ESSENTIALS—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
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Local Area Networking—NETWORKING ESSENTIALS—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
LOCAL AREA NETWORKING Intro to TCP/IP ARPANET formed (basis for Internet) TCP/IP adopted as protocol for ARPANET/the Internet IP addresses have four octets between 0-255 (a total of 256 options) Classful address scheme for locations & sublocations. Class A—6.x.x.x Only 1st number is locked millions of hosts Class B—172.16.x.x First 2 numbers are locked/set 65,534 hosts Class C—210.11.12.x First 3 numbers are locked/set) 254 hosts Network IDs and Subnet Masks Use Network & Sharing Center for setting up network information Set IP address, subnet mask, and gateway in Ethernet Properties Manual settings = static IP address Private IP Addresses: Class A—10.x.x.x Class B—172.16.x.x, 172.31.x.x Class C—192.168.x.x Special IP Addresses Class…
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Physical Networking—NETWORKING ESSENTIALS—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
PHYSICAL NETWORKING Introduction to Networking LAN computers connect with Ethernet. (Local Area Network) Ethernet frames standardized as 1500 bytes A MAC address uniquely identifies a host on a LAN. (MAC-Media Access Control; a MAC is a 48-bit address; always manifested as 12 hexadecimal characters) Use ‘ipconfig’ (Windows) or ‘ifconfig’ (Linux) to view MAC. Example MAC address: xx-xx-xx-xx-xx-xx (the first 3 sets of pairs combined together are known as the OEM ID. Hubs vs. Switches Hubs repeat all traffic on LAN to all nodes (Hub = ‘dumb’ repeater) Switches filter traffic based on MAC address (Switch = smart repeater) Switches provide full bandwidth for all nodes Hexadecimal Hexadecimal (base 16) enables…
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Display Technologies—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
Display Technologies Monitor Technologies A monitor is composed of individual picture elements (pixels); the total pixels across and down is the resolution. Liquid Crystal Display (LCD) monitors use liquid crystals to allow light to pass or not pass for each color in a pixel. LCD backlights are fluorescent or LED lights & shine through the liquid crystals. Organic LED (OLED) doesn’t use a backlight, as the pixels make their own light. Digital Light Processing (DLP) uses a grid of tiny mirrors that shine through a color wheel to create an image. -CCFL—Cold cathode fluorescent lamp—1st generation LCD’s LED—Light-emitting diodes The imaging (front) is LCD and the backlighting can be CCFL…
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USB (Universal Serial Bus) Standards—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
USB Standards Standard USB Speeds: Low-speed USB USB 1.1—-1.5 Mbps Full-speed USB USB 1.1—-12 Mbps Hi-Speed USB USB 2.0—-480 Mbps Super-Speed USB USB 3.0—-5 Gbps SuperSpeed USB 10 Gbps USB 3.1 Gen 2—-10 Gbps Types USB A—’normal’ USB interface Mini USB—for some cameras Micro USB—for some phones USB C—New interface model that plugs in in either direction. Quick Review Universal Serial Bus (USB) 1.1 comes in 1.5 MB/s & 12 Mbps; USB 2.0 runs at 480 Mbps USB 3.0 runs at 5 Gbps; USB 3.1 runs at 10 Gbps USB versions often use colors to indicate version USB connectors come in many types: Type-A; Type-B; Type-C; Standard; Mini; and Micro.…
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Mass Storage Technologies—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
Introduction to Mass Storage There are many types of mass storage used today, including hard drives, solid state drives (SSD) and optical media. Regardless of the media, your operating system sees mass storage as a string of logical block addresses. There is a difference between decimal value and IEC values. LBA—Logical Block Address Decimal Counting— 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 Kilo 1,000 Mega 1,000,000 Giga 1,000,000,000 Terra 1,000,000,000,000 Peta 1,000,000,000,000,000 Exa 1,000,000,000,000,000,000 Binary—more concerned with how many possible patterns IEC Values: There can be (IEC counting) 00000000 28 = 256 different patterns (LBA values) 210 = 1024 different patterns Kibi = 210 (Not “kilo”…
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BIOS & Intro to Core Hardware & Firmware—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
Firmware What is BIOS/UEFI? BIOS programs are code. Basic Input/Output Services Note: Every motherboard in existence has built-in to it a small program designed to let us talk to the assumed hardware of the computer, and it’s called, ‘BIOS’. BIOS is a firmware, burned onto a chip, as opposed to software, which is copied onto some type of magnetic media or electronic media. BIOS programming enables interaction with the motherboard before the OS loads. BIOS is stored in non-volatile media, thus called firmware. POST (Power On Self Test) routines are built into firmware. The System Setup utility is also part of the firmware. (CMOS) POST—Power On Self Test POST runs…
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The Visible Computer—CompTIA A+ (220-1001) A-PLUS Certification Prep Course Notes
The Visible Computer A computer gets work or play done. A computer will have a CPU, RAM, mass storage, & an OS. Primary PC Components System unit, Monitor (output), Keyboard & mouse (input), Printer (paper output); Speakers, game controllers, web cameras, external hard drives, headsets, microphones. External Connections USB, network cable connections (RJ45); DVI; HDMI; older: mini-din (PS2); Parallel port; serial port; VGA. Inside the PC What is a computer? What is an Operating System? A program that runs the other programs (the conductor). An OS controls all the programs on a computer. Kernel—the core part of the OS that handles the primary memory management. The core of the operating…
