Mobile Devices Flashcards
SO-DIMM
Small Outline Dual In-Line Memory Module
Used to add memory to a laptop
Magnetic Disk
Laptop Storage
Traditional spinning drive platters
2.5 form factors
3.5 for desktops
SSD
Solid State Drive
Laptop Storage
All memory, no moving parts
Silent, fast access time, less latency
2.5 in form factors
M.2
Laptop Storage
Smaller form factor
No SATA data or power cables
Easy to install and replace
HDD
Hard Disk Drive
Memory
Migrating from HDD to SSD
Install an OS on the SSD
Move user documents between drives
Install any required applications
Can be time consuming
Different ways to migrate from HDD to SSD
- Install an OS on the SSD
Move user documents
between drives
Install any required
applications - Image/Clone the HDD
No OS installation
required
Move everything from
one to the other
Imaging software is
needed - Create and image file
One drive at a time - Drive to drive image
Image directly from one
drive to the other
802.11
LAN, high speed, internet access
LAN
Local Area Network
Bluetooth
PAN
Short Range
Connect peripherals and other nearby devices
PAN
Personal Area Network
Biometrics
Sign-in/unlock option on your devices
Fingerprint or face
NFC
Near-Field Communication
Short-Distance networking (~4cm)
Data transfers or authentication
LCD
Liquid Crystal Display
Light shines through liquid crystals
Advantages:
Lightweight
Relatively low power and inexpensive
Disadvantages:
Black levels are a challenge
Requires separate backlight (Fluorescent, LED, etc) and are difficult to replace
TN LCD
Twisted Nematic
Original LCD tech
Fast response times (gaming)
Poor viewing angles (color shifts)
IPS LCD
In Plane Switching
Excellent color representation
More expensive to produce than TN
VA LCD
Vertical Alignment
A good compromise between TN and IPS
Good color representation
Slower response times than TN
OLED
Organic Light Emitting Diode
Organic Compound emits light when receiving an electric current
Thinner and lighter (no glass needed)
No backlight
OLED Examples
Tablets, phones, smart watches
Wifi antennas in Laptops
Multiple
1. Wifi main and aux (wire wraps about the laptop screen)
2. Bluetooth
Webcam in Laptops
Built in camera and microphone
- Specialized drivers and software
Microphone in Laptop
Built-in
-Useful for video calls
-Not good for non-casual use
-Analog or USB microphones can help
Fluorescent Backlighting in Laptops (CCFL)
-Cold Cathode Fluorescent Lamp
-Higher voltage and power needed that LED backlighting
-Added thickness to the display
-Found more often in older laptops
LED-backlit LCD display
-LEDs are located around the edge of the screen
-An array of LEDs behind the screen
-Most new laptops are LED-backlit
LCD Inverter
-Some laptops have inverters
-Turn DC (computer power) into AC (fluorescent power)
Digitizer
-Use a pen-like device as input
-Stylus input
-Useful for graphical input
Touchscreen device
-Merge laptop and tablet input
-Digitizer responds to touch
-No keyboard required but often available
USB
-Universal Serial Bus
-High-speed wired communication
-Used for charging and data transfers
-Type A (normal)
Micro-USB
-A smaller USB connection
-Common now worldwide
Mini-USB
-Used by older devices
-Slightly larger
USB-C
-24-pin double-sided USB connector
-Used for both hosts and devices
-Acts as a USB 2.0/3.0/3.1/4 connection
–different signals can use the same connector
-Can transmit other signals (DisplayPort, HDMI, Thunderbolt)
Lightening Cable
-Apple proprietary
-8-pin digital signals
Advantages over Micro-USB:
-Higher power output for phones and tablets
-can be inserted either way
-simpler design
Serial Interfaces
-“DB-9”
-Commonly used for RS-232 signals
—Recommended Standard 232
- Standard before USB
–traditionally used for modem connection
-Used now as a configuration port (switch, routers, firewalls, etc)
NFC
-Near Field Communication
-Send small amounts of data wirelessly over a limited area
-Short range w/ encryption support
Hotspot
-Turn your phone into a wifi hotspot
-Your own personal wireless router
-Extend the cellular data network to all of your devices
Touch pens
-Touchscreen Pen/Stylus
-Activate the interface without actually touching it
Active Stylus
-Digital Stylus
-The stylus communicates directly to the device
-Must be compatible with the tablet (Apple Pencil to Apple iPad)
Drawing Pad
-Use an active stylus with an external digitizer (very precise input)
-Third-party device (support across many operating systems
Trackpad
-Replaces the mouse
-Can enable or disable
-External options available
Headsets
-Wired
-USB connections are common on laptops
-Connects to 3.5mm TRRS (tip-ring-ring-sleeve) connector
-Analog audio jack
-iPhones can use lightening port
Docking Station
-Use external keyboard and mouse
-Extend existing laptop interfaces
-Add additional functionality
-Desktop adapter cards
Port replicator
-Similar to a docking station
-Does not commonly have an expansion card option
-Usually connects using USB
GSM
Global System for Mobile Communication
-Mobile networking standard
-90% of the market
-Used by at&t and t-mobile
-(move your SIM card from phone to phone)
-Slice of time
SIM card
Subscriber Identity Module card for phones
CDMA
-Code Division Multiple Access
-Everyone communicates at the same time
-Each call uses a different code
-The codes are used to filter each call on the receiving said
-Used by Verizon and Sprint
-Handsets are controlled by the network provider
3G tech
-3rd generation
-Upgraded data connectivity over 2G
-Bandwidth improvement allowed new functionality (GPS, mobile television, video on demand)
4G and LTE
-‘Long Term Evolution’
-Converged standard (GSM and CDMA)
-Standard supports download rates of 150Mbit/sec
4G LTE-A
-LTE - Advanced
-Standard supports download rates of 300Mbit/s
5G
-Significant performance improvements
–At higher frequencies
-Eventually 10gigiabits/sec
-Slower speeds from 100-900 Mbit/s
-Significant IoT impact
-Bandwidth becomes less of a constraint
-Larger data transfers
-Faster monitoring and notification
-Additional cloud processing
PRL Updates
-Preferred Roaming List
-CDMA networks (ie Verizon and Sprint)
-Allows your phone to connect to the right tower
-Can be updated Over The Air (OTA)
GPS
-Global Positioning System
-Created by DoD
-Over 30 satellites in orbit
-Need to see at least 4 satellites to measure timing differences
MDM
-Mobile Device Management
-Manage company-owned and user-owned mobile devices
-Set policies on apps, data, camera, etc
-Manage access control
–Force screen locks and PINs on these single user devices
MDM Configuration
-Corporate email configuration
-Two factor authentication (biometrics, pseudo-random authentication app)
-Allow or restrict app installation
-prevent unauthorized app usage
TCP
TCP
UDP
-User Datagram Protocol
-Connectionless (no formal open or close to the connection)
-“Unreliable” delivery
–No error recovery
–No reordering of data or retransmissions
-No flow control
–Sender determines the amount of data transmitted
Why would you ever use UDP?
-Real-time communication
-There’s no way to stop and resend the data
-Time doesn’t stop for your network
-DHCP (Dynamic Host Configuration Protocol)
-TFTP (Trivial File Transfer Protocol)
Communications that use TCP and why
-Connection-oriented protocols prefer a ‘return receipt’
-HTTPS (Hypertext Transfer Protocol Secure)
-SSH (Secure Shell)
-The application doesn’t worry about out-of-order frames or missing data
-TCP handles all of the communication overhead
Non-ephemeral ports
-Permanent port numbers
-Ports 0-1023
-Usually on a server or service
Ephemeral ports
-Temporary port numbers
-Ports 1024 through 65,535
-Determined in real time by the client
Port Numbers
-TCP and UDP ports can be any number between 0-65,535
-Most servers use non-ephemeral port number
-Port numbers are for communication not security
-Service port numbers need to be well-known
-Important for firewall rules (port-based security)
FTP
-File Transfer Protocol
-tcp/20 = active mode data
-tcp/21 = control
-Transfers files between systems
-Authenticates with a username and password
-Some systems use a generic/anonymous login
SSH
-Secure Shell
-Encrypted communication link
-tcp/22
-Looks and acts the same as Telnet
Telnet
-Telecommunication Network
-tcp/23
-Login to devices remotely (console access)
SMTP
-Simple Mail Transfer Protocol
-Server to server email transfer
-tcp/25
-Also used to send mail from a device to a mail server
Other protocols are used for clients to receive emails (IMAP, POP3)
DNS
-Domain Name System
-Converts names to IP addresses
-upd/53
DHCP
-Dynamic Host Configuration Protocol
-Automated configuration of IP address, subment mask, and other options
-udp/167, udp/168
-Requires a DHCP server
DHCP Dynamic/Pooled
-IP addresses are assigned in real-time from a pool
-Each system is given a lease and must renew at a set interval
DHCP Reservation
-Addresses are assigned by MAC address in the DHCP server
-Manage addresses from one location
HTTP
-Hypertext Transfer Protocol
-Communication in the browser and by other applications
-tcp/80
HTTPS
-Hypertext Transfer Protocol Secure
-Secure communication in the browser
-Encrypted
-tcp/443
POP3
-Post Office Protocol version 3
-Receive emails from an email server
-Authenticate and transfer
-tcp/110
-Basic mail transfer functionality
IMAP
-Internet Message Access Protocol v4
-tcp/143
-Receive emails from an email server
-includes management of email inbox from multiple clients
SMB
-Server Message Block
-Protocol used by Microsoft Windows
-File sharing, printer sharing
-“CIFS” - Common Internet File System
-using NetBIOS over TCP/IP (Network Basic Input/Output System)
–udp/137 = NetBIOS name services (nbname)
–tcp/139 = NetBIOS session service (nbsession)
-Direct over tcp/445 (NetBIOS-less) (Direct SMB connection over TCP w/o the NetBIOS transport
SNMP
-Simple Network Management Protocol
-Gather statistics from network devices
-udp/161 = queries
-udp/162 = traps
LDAP
-Lightweight Directory Access Protocol
-tcp/389
-Store and retrieve information in a network directory
-Commonly used in Microsoft Active Directory
RDP
-Remote Desktop Access Protocol
-Share a desktop from a remote location
-tcp/3389
-Can connect to an entire desktop or just an application
-Clients for Windows, macOS, Linux, UNIX, iPhone, Android, and others
