CompTIA A+ 2 Flashcards
How many DNS servers must you have in your IP configuration?
2.
What is an IP helper address?
Also called a DHCP Relay address, it is an address outside of your local network where a router will send DHCP requests that it receives.
Computers broadcasting for a DHCP server will send a broadcast request to what destination port?
UDP port 67.
Servers sending a DHCP broadcast back to computers will send to what destination port?
Port 68.
What is APIPA?
Automatic private IP addressing.
Aka a link-local address.
- no forwarding by routers.
IETF has reserved 169.254.0.1 - 169.254.255.254
- first and last 256 addresses are reserved.
- can use: 169.254.1.0 - 169.254.254.255
Automatically assigned.
- uses ARP to confirm address isn’t already taken on your network.
What is an IPv6 link-local address?
Required on every IPv6 enabled interface.
fe80: :/10 with only one subnet allocated.
- effectively becomes fe80::/64.
The last 64 bits are usually created with a modified EUI-64.
- based on the MAC address.
What is WiMAX?
Worldwide interoperability for Microwave access.
- wireless high speed internet access.
A line-of-sight service.
What is a WAN?
A wide area network.
Basically, connecting to devices across the globe.
What is a MAN?
A metropolitan area network.
Larger than a LAN, smaller than a WAN.
What is a WMN?
A wireless mesh network.
Connect to each other automatically.
Automatically react to changes.
(Like Zigbee).
What is a tone generator?
Puts an analog sound on a wire, then you listen for that sound with another device, like wire tracing.
What is Plenum airspace?
Shared airspace in a ceiling where cabling is run as well as HVAC air return, it’s a tie hazard.
If running cable in plenum airspace in a ceiling, what kind of cable do you need?
A fire-rated cable jacket.
FEP or low-smoke PVC.
A traditional cable jacket is pvc and is a fire hazard.
What does F/UTP mean on a cable?
Foil around the cable and no shielding around the pairs.
What does S/FTP mean on a cable?
The cable is shielded and there is foil around each pair.
What do T568A and T568B mean?
They are the pin assignments from EIA/TIA-568-B standard (used for Ethernet).
You can’t have the two ends of the cable each using one, they must both be A or B.
What are the two types of coaxial cable?
RG-6
Used in television, digital cable and high speed internet.
RG-59
Used as patch cables, not designed for long distances.
Coaxial cables:
Wire conductor inside a (foam looking) dielectric insulator inside a metal shielding inside a plastic jacket.
What is multimode fiber?
Fiber for short range communication.
2km for 100 Mbit/s
550 meters for 10 Gbit/s
Usually used with an inexpensive light source like an LED.
Several lights bouncing around in one tube.
What is single mode fiber?
For very long distances, over 80km without additional processing.
Expensive light source, like a laser.
One straight light through a narrow tube.
VGA cables have what kind of connector?
DB-15.
(Or DE-15)
Analog signal, so degraded after 10 or 15 meters.
How far can HDMI cables extend without losing quality?
20 meters.
What is a DVI-A?
DVI analog.
Flat bar with 4 pins surrounding.
What is DVI-D?
DVI digital.
What is DVI-I?
Integrated. Both analog and digital.
Difference between single and dual link DVI cables?
Single: 3.7 Gbps (HDTV at 60 FPS)
Dual: 7.4 Gbps (hdtv at 85 FPS).
A thunderbolt v1 or v2 cable uses what type of connector?
An MDP, mini display port standard.
Data and power.
Several versions.
A thunderbolt v3 cable uses what connector?
USB-C.
Maximum length 3 meters with copper. 60 meters with optical.
Can daisy chain up to 6 devices.
USB 3.0 can extend to about what length?
~3 meters.
A DB-9 serial cable connector is commonly used for what?
As a configuration port (serial console interface).
Built for modem communication (modem, printer, mouse, networking).
Commonly used for RS-232.
(Recommended standard 232).
Different sizes A-E.
DA-15, DB-25, DC-37, DD-50, DE-9.
SATA connections have what 2 types of connectors?
A power connector and a data connector (which goes to the motherboard).
What is PATA?
Another name for ATA, the thing before SATA.
What is SCSI?
Small computer systems interface.
Parallel and serial versions exist.
Originally designed to string many devices together with one cable/controller.
- up to 16 in a SCSI “chain.”
Many types of interfaces.
What is a BNC connector?
Bayonet Neil-Concelman
Coaxial cable connector
- DS3 WAN links.
Rigid and bulky
- can be difficult to work with.
What is an F-connector?
RG6 or RG-59.
The screw in coax cable such as for cable tv.
What shape is a SATA connection?
L-shape.
What shape is a eSATA connection?
Rectangle inside a rectangle with ears on the side.
What is a Molex connector?
4-pin peripheral power connector.
Provides 12v and 5v.
Rectangle with 4 circular pins and 2 or the corner notches cut out.
Aka an AMP MATE-N-LOK.
What is parity memory?
RAM used in critical computer systems.
Adds an additional parity bit for error checking. (Not 100% detection).
Can’t correct errors.
What is ECC memory?
Error correcting code RAM used in critical computer systems.
Detects errors and corrects on the fly.
Looks the same as non-ECC memory.
What is an M.2 interface?
PCIe bus connection drive with no cables, plugs directly in. Very fast.
Looks like a stick of RAM.
Uses a notch called a B Key, an M Key or both.
What is RAID 0?
Called striping.
File blocks are split between two or more physical drives.
NO redundancy.
What is RAID 1?
Mirroring.
Duplication among two or more drives.
What is RAID 5?
Striping with parity.
Complete redundancy by using parity blocks.
Requires at least 3 disks.
Efficient use of disk space, no actual duplication.
What is RAID 10 (1+0)?
A stripe of mirrors.
The speed of striping and the redundancy of mirroring.
Need at least 4 drives.
Learn what are the important motherboard form factors?
ATX, microATX, ITX and mini-ITX.
What is the UEFI bios?
Unified extensible firmware interface.
Common bios standard.
Designed to replace legacy bios.
Graphical and text-based.
Can boot from very large drives, over 2+ terabyte.
Has a pre-boot environment that is not an operating system but gives functionality.
Does CMOS have a battery nowadays?
No, batteries on motherboards nowadays are used for keeping the date and time.
There may be a jumper on a modern motherboard that allows resetting the bios though.
How to check windows bios version and other info?
Type msinfo32 into run.exe.
What is hyperthreading?
Making one cpu run as if it is multiple CPU’s.
What is BCLK?
Base clock.
The cpu clock speed.
To overclock, the cpu must be unlocked.
Also, it will void the warranty.
What is a TRS connection?
Tip ring sleeve. For audio.
TRRS is tip ring ring sleeve, the extra ring is for a microphone.
