1001 Flashcards
Advantages of LCD
- Lightweight
- Low power Usage
- Relatively Inexpensive
Disadvantages of LCD
- Struggles to display true black due to backlight
- Requires seperate backlight
- Difficult to replace
How does OLED work?
- Organic compounds that emit light when receiving an electric current.
Advantages of OLED
- Thinner and lighter
- No glass required
- No backlight leading to better colour representation
Disadvantages of OLED
- Organic materials decay over time
- Decayed images can remain on screen
- Costly
- Power Hungry
Keyboard hotkey for dual display options
FN + F4
What is a LCD Switch?
Displays to another screen when laptop is closed. Physical switch on older systems but newer ones use a magnetic strip. Functionality can be altered in the BIOS.
What are the possible wireless control options on a laptop?
Physical switch
Function Key
What does GPS stand for?
Global Positioning System
How do GPS devices work?
Location is determined via GPS signal. GPS requires periodic updates and needs a view of the sky.
What are the different types of headsets?
Hands-free audio (earphones + microphone)
Wired
Wireless
What is the a TRRS connector?
Tip-Ring-Ring-Ring Sleever
Also known as 3.5mm jack.
Used in wired headsets
Whats the difference between a Screen Protector and a Device Protector?
Screen protector covers the screen. It prevents scratches but can be difficult to install.
A device protector wraps around the entire device. It can be waterproof but tends to cause an issue for docks/wireless chargers.
How can credit card readers connect to a phone?
- Audio/mic connections (TRRS Jack)
- Lightning connector
- USB
- Bluetooth
What type of network is Bluetooth?
PAN (Personal area network)
What is PRL
Preferred roaming list.
What are the types of cellular networks?
GSM - Used globally
CDMA - Used in American & Russia. Higher capacity (uses whole band).
No SIM so is locked to network provider.
What are PRI updates?
Product Release Instructions.
Updates specific radio settings such as ID numbers, network codes, country codes.
Updated over the air.
What are the two ways used to identify mobile devices.
IMEI - International Mobile Station Equipment Identity.
- Identifies phones.
- Unique to each phone
IMSI - International Mobile Subscriber Identity
- Identifies user of the network.
- Common on SIM Card (allows data etc to be carried over as SIM card does).
What is FTP?
- File Transfer Protocol
- Allows the transfer of files between Systems.
- Can be encrypted using username/password
- Supports anonymous log in (anon username any password)
- Full featured functionality - allows control of files on target system.
What is the tcp/20 port?
FTP Active mode data port
What is tcp/21 port?
FTP Control port
What is SSH and how does it work?
- Secure Shell
- tcp/22
- Encxrypted communication link via console.
- Looks and acts the same as Telnet
What is Telnet?
- Telecommunication network
- tcp/23
- Older version of SSH, used in legacy devices with no SSH support.
- Allows login to devices remotely and is not encrypted.
What is SMTP?
- Simple mail transfer protocol
- Server to server email transfer.
- Commonly used to send mail from a device to a mail server (computers and mobile devices)
Name what technologies belong to which protocol: tcp/20 tcp/21 tcp/22 tcp/23 tcp/24 tcp/25 tcp/80 tcp/110 tcp/139 tcp/443 udp/53 udp/137 udp/138
tcp/20 - FTP Active protocol tcp/21 - FTP control protocol tcp/22 - SSH (Secure Shell) tcp/23 - Telnet (Telecommunication Network) tcp/25 - SMTP tcp/80 - HTTP tcp/110 - POP3 tcp/143 - IMAP4 tcp/389 - LDAP tcp/443 - HTTPS tcp/427 - Service Location Protocol tcp/445 - NetBIOS-less tcp/548 - Apple Filing Protocol tcp/3389 - RDP udp/53 - DNS udp/67 - Dynamic Host configuration protocol #1 udp/68 - Dynamic Host configuration protocol #2 udp/137 - Netbios Datagram Services udp/138 - Netbios Session service udp/161 - SNMP Queries udp/162 - SNMP Traps udp/427 - Service Location Protocol
What are the alternatives to SMTP (2)
IMAP
POP3
What is DNS and how does it work?
Domain Name System --------------------------------- - udp/53 - Upon typing URL sends request to DNS server which responds with required IP for webserver. -
What does tcp stand for?
Transmission control protocol
What does UDP stand for?
User Datagram Protocol
Explain Http / Https
Hypertext Transfer Protocol.
- HTTPS is the “secure” version and is encrypted.
Explain POP3
Post office protocol version 3
tcp/110
Provides basic mail transfer functionality.
Expain IMAP4
Internet message access protocol v4
tcp/143
Allows mail transfer but additionally allows management of email inbox from multiple devices.
Explain RDP
Share a desktop from a remote location.
Uses tcp/3389
Works on many versions of windows. also versions for other OSs.
Explain SMB
Standard set of prococols Windows uses for file sharing, printer sharing etc.
Also referred to as CIFS (common internet file system).
Explain Netbios
Legacy Windows communication. Netbios inside UDP or TCP packet.
What is NetBIOS naming services (nbname), and what port does it use.
Allows the system to find a device on a network by it’s name.
Uses Port udp/137
What is NetBIOS datagram services (nbdatagram) and what port does it use?
Uses, receives and sends datagrams over a network.
Uses port udp/138
What port does NetBIOS session service (nbsession) use?
Uses port tcp/139
Why is Netbios now redundent?
Current windows do not have to parse between NetBIOS types, can directly communicate over tcp/445 (NetBIOS-less) .
What is Apples MAC protocols
Apple Filing Protocol
- Uses port tcp/548
- Max OS file protocol allows users to access outside system files.
- Additionally provides security features to restrict user access to files.
Explain SLP
Service Location Protocol
- Method of organising and locating resources (e.g. printer, disk drives, databases) in a network.
- Allows the re-arrangement and management of services, or installation without reconfiguring individual workstations.
- Uses tcp/427 & udp/427
Explain DHCP
Dyanmic Host Configuration Protocol
- Automated configuration of IP address, subnet mask & other options.
- This allows device to communication via IP.
- IP is leased for a certain time, DHCP server needs to be checked periodically to ensure IP is okay else re-assign it.
- DCHP can be configured for reservations. DCHP server can recognise MAC address and provide same IP each time.
- Uses ports: udp/67, udp/68
Explain LDAP
Lightweight Directory Access Protocol
- For accessing and maintaining distributed directory information services over an IP network.
- Commonly used in Microsoft Active Directory.
- Primary place for storing network authentication.
- tcp/389
Explain SNMP
Simple network management protocol ------------------------------------------------ - Queries using udp/161 - Traps udp/162 Gather statistics from network devices.
What is a SNMP trap?
SNMP traps enable an agent to notify the management station of significant events by way of an unsolicited SNMP message.
What are the three different versions of SNMP
V1 - The original - non-encrypted - structured tables
V2 - Data type enhancements, bulk transfers, non-encrypted
V3 - Message integrity, authentication method, encrypted.
What hardware does a device require to connect to a network?
- Network interface card,
- One per network type (e.g. wifi, lan)
- Often built into motherboard
What options are availabe for Network interface cards?
Single Port
Multi port - Multiple ports of same type (e.g. 2x ethernet ports)
- Copper
- Fibre
What does a repeater do?
Receives a signal, regenerates it and then resends
Why are repeaters used?
- To boost copper or fibre connections
- Convert network media (e.g. fibre to copper)
- Extend wireless network reach.
What is a multi-port repeater?
Traffic sent to one port is repeated to every other port
What are the characteristics of multi-port repeaters?
- Everything is half duplex (only one device can send data at a time)
- Becomes less efficent as network speeds increase.
- Can only find in 10/100 megabit
- Uncommon today.
What does a bridge do?
- Hub networks connected via bridge. Bridge would make decision on how traffic should be routed.
- Can connect different physicalk network. e.g. can connect a wired network to a wifi one.
- Instead of a hub bridge will send via MAC address.
Describe the characteristics of a Network Switch
- Control device that connects devices on a computer network using packet switching to receive and forward data to the destination device.
- Allows the sharing of data across a network.
- Uses ASIC
- Determines where to send based on MAC address.
Explain the two types of switches
Unmanaged switch - Works out of the box, cannot be configured. Typically tend to be cheaper
Managed Switch - Can be configured. Can monitor locally and remotely.
What does ASIC stand for?
Application specific integrated circuit
What does MAC address stand for and what does it mean?
Hardware identification number which identifies a device on a network.
What is a router?
- Device that routes draffic between IP subnets
- Used for diverse network types (lan, wan, copper etc)
What is a Wireless access point (WAP)
- Extends a wired network to a wireless network.
- Makes forwarding network based on MAC address
What is a wirless router?
A router and a WAP in a single device.
What is a wireless LAN controller?
- Device which manages WAPs. Can also provide management functions
- Allows employement of new access points
- Peformance and security monitoring
- Deploy and configure blanket changes
- Report on usage
- Usually proprietary but can be cloud.
What is a firewall?
- Allows the filter of info based on port number.
- Some firewalls can filter based on application
- Can encrypt traffic in/out of network.
- Can act as a proxy
Cable Modem
- Provides Broadband
- Can transmit across multiple frequencies
- Supports multiple traffic types
- Data sent via DOCSIS standard.
What is DOCSIS?
Data over cable service interface specification. Supports multiple services, e.g. video, voice
DSL Modem
- Uses ADSL
Data sent over telephone lines
What does ADSL stand for and what does it mean?
Asymmetric Digital Subscriber Line
- Download speed > upload speed
- 10,000 foot limitation from central office and jack inside of home.
What is a patch panel?
Panel terminates individual wires under 110 block. (e.g. in an office space)
Facilitates a patch between individual workstations and networking equipment. Allows easy configuration.
RJ45 Connectors
Go all the way back to persons individual desk.
Define POE
Power over Ethernet
How does Power over Ethernet work?
Single cable to provide both network + power.
Power provided from switch (endspan)
What is a POE injector?
Sometimes devices require POE but switch does not support power providing. In those cases a POE injector can add power to ethernet connection (midspan)
How to identify PoE supported switch?
Reads on the switch (e.g. “PoE + managed switch)
Defined EOP
Opposite of EOP. Power cables used to provide ethernet. Alternatively called POL (powerline communication).