CMAP Flashcards
Clock
Frequency timings that is processed by the CPU. these timings can be differentiated for buses
SCSI
Small computer system interface: Legacy parallel bus: supporting 320 MBps.
devices must be configures with identifier 0-15
Where is SCSI found
SAS interfaces for enterprise-class storage devices
IDE
integrated drive electronics: legacy mass storage interface using PATA (parallel advanced technology attachment)
Adaptor cable
cable that carries at least two connectors for different devices
DC
direct current converted from AC drawn from the wall.
What types of VAC (volts of alternating current) are there
Low-line 120 VAC US : High-line 220-240 VAC UK.
PSU will be marked which can be used unless specified auto-switching
Wattage rating
ensure the wattage amount and efficiency of power pulled to use
Wire Volts: yellow, red, orange, black
12, 5, 3.3, ground
What CPU fan components regulate heat
Heat sink: applying cooling via convection.
Thermal paste: ensure best transfer of heat.
SSD
Solid-state drive: smaller then HD using flash memory
SLC most reliable
contain slot keys noticable on m.2 adptors: B usually, and m, B/M
Advanced host controller interface (AHCI)
allows SATA modern ssd to communicate over the PCIe bus improving performance
NVMe
non-volatile memory express: the bus PCIe based SSD’s use
HDD
hard disk drive: contains plater, spindle, read/write head and actuator.
how is HDD drives speed measured
high perfomrance 15k or 10k rpm
low medium 7.2k or 5.4k rpm
what is involved with RAID 0
Striping: splitting data into independent disks improving performance but no redundancy
what is RAID 1
mirroring: only boosting performance a little bit but copies date to each independent disk identically.
what is RAID 5
Stripping with parity: requiring 3 or more disks but using more increases chance of fault, and repairing a disk with parity bit slow performance
What is RAID 10
stripe with mirror: independent volumes containing drives, two volumes receive split data and disk in the volume copy each other in the volume
NAS
network attached storage: connects directly to network rather than pc. assist in file servers
DRM
digital rights management found on DvD and blue-ray but also manages region coding.
Virtual RAM
storage assigned by the OS to store temporary information to free up space to retrieve when needed; otherwise know as swap space
what does Synchronus DRAM do
SDRAM syncs its speeds to the motherboards clock
what does Double Data Rate SDRAM do
makes 2 transfers per clock cycle on motherboard
How to determine peek transfer rate in RAM
MT/s * 8 bytes = MBps / 100 = GBps
what happens if the full memory module is not installed in tri/quad channels
channel will be not recognized and will revert back to what are populated
UDIMMS
Un-buffed Ram modules, traditional but differ from ECC although they can contain ECC but wont work in environment that use RDIMMS (registered)
ECC require 72-bit bus from motherboard and additional CPU chip.
ARM
Advanced RISC Machines: using SoC (system on chip) where all controllers are apart of the CPU.
PGA & LGA
CPU socket form fators
pin grid array
land grid array
Server CPUs chip sets
Intal Xeon and AMD Epyc
HDD sizes
PC 3.5 in
laptops 2.5 in with varied heights 17, 9.5, 7, 5 mm
memory cards speeds
UHS 1 108 MBps -
2 156 MBps full or 312 (FD)half duplex -
3 312 MBps full or 624 (FD)half duplex
memory card storage SD, SDHC, SDXC
2GB, 32GB, 2TB
Lighting Connector
Apple proprietary connector
Thunderbolt
similar to DisplayP: can support display interfaces up to 20 Gbps. similar interface a USB-C
USB
Universal serial bus, in theory can connect to 127 devices er controller
HDMI Premium and Ulta speeds and DisplayP
Premium: up to 18 Gbps
Ultra: up to 48 Gbps
DisplayP: up to 20 Gbps
LCD
liquid crystal display and thin film transistor type
FPS vs Hz
frames per sec refers to the video source.
Hertz is refresh rate.
Both should be equal or fps divisible by 2 based off Hz
what is the trouble shooting methodology?
- Identify the problem
- Establish a theory or probable cause
- Test the theory to determine the cause
- Establish a plan of action to resolve the problem and implement solution
5.Verify full-system functionality; (if possible), implement preventative measures
6.Document findings, actions, and outcomes.
Secure boot
UEFI feature: computer firmware is configured with cryptographic keys to identify trusted code of the OS vendor. Keeping track of boot loaders modified with malware will no permissions.
crypto graphic process
A secure hash using unique code from generated input. Comparing hashes to verify similarity, but original data cannot be recovered.
TPM
Trust Platform Module: Coded as a unique unchangeable key (endorsement key). A motherboard chip that stores digital certificates, cryptographic keys, and hash passwords.
HSM
Hardware security module: device like USB functions as the TPS’s store for cryptographic material. Requires authentication to access contents.
POST
power-on self-test: diagnostic program implemented in system firmware
IBM PC Code: “1 short beep”
normal POST - system okay
IBM PC Code: “2 short beeps”
POST error -error shown on screen
IBM PC Code: “no beep”
Modern PC’s are configure to boot silently, but could mean Power supply, motherboard problem, or faulty on board speaker.
IBM PC Code: “Continuous beep”
Problem with system memory modules or memory controller.
IBM PC Code: “Repeating short beeps”
Power supply fault or motherboard problem
IBM PC Code: “1 long, 1 short beep”
Motherboard problem
IBM PC Code: “1 long, 2 or 3 short beeps”
Video adaptor error
IBM PC Code: “3 long beeps”
Keyboard issues (check key is not depressed)
SMART
Self-monitoring, Analysis, and Reporting technology: can alert OS of failures. can run advanced diagnostics. can report IOPS statistics.
RTC
Real time clock chipset. keeps track of date and time with battery power.
What ethernet standard are LANs based on?
802.3 ethernet: over copper cabling
100BASE-T -Fast ethernet 100MB
1000BASE-T -Gigabit ethernet 1000MB
10GBASE-T -10G
What standard is used over WLAN?
IEEE 802.11 (Wi-Fi):
SAN
storage area network: provisioning storage devices for server application not accessible by client PC’s.
Use connectivity such as Fiber and internet SCSI
Hub
legacy network device utilizing 10BASE-T and 100BASE-T ethernet cabling. all devices receive traffic referring to it as a collision domain.
managed vs unmanaged switch
unmanaged switch carries out its function will no need of configuration.
managed switches, can connect over a management port and configure security settings.
Power over ethernet standards
802.3af: 13W - 15.4 with V drop at 100m
802.3at: [PoE+] 25W draws (current 600mA)
802.3bt: [PoE++ or 4PPoE] 51W T3 73W T4
Power injector
Device provides PoE via a port connection to a switch that doesn’t supply it.
why must STP cables be bonded
to prevent the metal from acting as a large antenna.
Twisted pair cable speeds and Cat
CAT:
5 -100 Mbps 100m
5e - 1Gbps 100m
6 - 1G 100m or 10G 55m
6A - 10Gbps 100m
Network Tap
intercepts signals over cabling.
passive TAP intercepts all signals regardless of integrity
Active TAP power to receive complex Gb signals pTAP cant.
Plenum cabling
Cabling uses treated PVC.
General non-plenum cabling uses PVC jack and insolation
OSP (Outside Plant) cables types
Aerial cable: strung between two poles or anchors.
Direct burial: laid and then covered in earth or cement
Conduit: provide more protection for buried cables.
2.4GHz
Wi-Fi frequency band better going through solid surfaces but can be congested with other wireless tech and interference with microwaves.
802.11a
5GHz frequency only. Rate of 54Mbps divided into 23 non-overlapping channels
DFS
dynamic frequency selection: introduced with IEEE 802.11a preventing interference with radar signals.
IEEE 802.11b
2.4 GHz frequency band released with but inferior to .11a with 14 channels.
IEEE 802.11g
upgrades 802.11b to 54 Mbps and same channels.
IEEE 802.11n
uses both frequencies over an AP called “dual band” and cheaper adapters. allows channel bonding combining 2 20 MHz channels to a single 40.
IEEE 802.11n
implements multiplexing - MIMO (multiple input multiple output) - referred to as Wi-Fi 4
decibel units (dB)
Signal strength measurement. value -65 dBm good signal less than -80 is suffering packet loss or drops.
long-range fixed wireless : LRFW
Bridges 2 networks via a wireless connection without laying cable.
if licensed by FCC, interference sources discovered can remove or shut them down legally.
LRFW: Point-to-Point
use 2 ground-based “high-gain” (directional) transmits up to 30 miles requiring minimal obstruction if physical objects.
RFID
radio frequency ID
NFC
Near Field Communications.
