MODULE 16 — OVERVIEW (EXAM CONTEXT)

Item Memorize
Module Number 16
Module Name Hacking Wireless Networks
Focus Wireless concepts, threats, attacks, tools, countermeasures

LEARNING OBJECTIVES (DO NOT SKIP — EXAM LIST)

Objective # Description
01 Summarize wireless concepts
02 Explain different wireless encryption algorithms
03 Explain different wireless threats
04 Demonstrate wireless hacking methodology
05 Explain wireless attack countermeasures

OBJECTIVE 01 — SUMMARIZE WIRELESS CONCEPTS


WIRELESS NETWORK — CORE DEFINITION

Term Definition
Wireless Network A network that uses radio-wave transmission to communicate at the physical layer instead of cables

MEMORY HOOK:
No wires = radio waves


WIRELESS COMMUNICATION MEDIUM

Component Explanation
Transmission Uses electromagnetic (EM) waves
Carrier Air
Nature Broadcast-based

EXAM TRAP:
Wireless = broadcast, not point-to-point.


WIRELESS NETWORK TERMINOLOGY (VERY HIGH YIELD)


GLOBAL SYSTEM FOR MOBILE COMMUNICATIONS (GSM)

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GSM Universal system for mobile data transmission worldwide

BANDWIDTH

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Bandwidth Amount of data transferred per second
Unit bits per second (bps)

ACCESS POINT (AP)

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Access Point Device that connects wireless devices to a wired network
Function Acts as a switch or hub

BASIC SERVICE SET IDENTIFIER (BSSID)

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BSSID MAC address of the access point
Role Identifies a wireless access point

EXAM TRAP:
SSID ≠ BSSID


HOTSPOT

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Hotspot Public wireless access location
Examples Airports, cafes, libraries

ASSOCIATION

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Association Process of connecting a wireless device to an AP

WIRELESS SIGNAL TECHNIQUES (VERY EXAM-IMPORTANT)


ORTHOGONAL FREQUENCY-DIVISION MULTIPLEXING (OFDM)

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OFDM Digital modulation using multiple orthogonal subcarriers
Benefit Higher data rates, reduced interference

MULTIPLE INPUT MULTIPLE OUTPUT (MIMO)

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MIMO Uses multiple antennas
Benefit Increased throughput and reliability

DIRECT-SEQUENCE SPREAD SPECTRUM (DSSS)

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DSSS Spreads signal over wide frequency band
Purpose Prevent jamming

FREQUENCY-HOPPING SPREAD SPECTRUM (FHSS)

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FHSS Rapid frequency changes
Purpose Reduce interception

MEMORY BLOCK (SIGNALS):
OFDM = speed, MIMO = power, DSSS = spread, FHSS = hop


WIRELESS NETWORKS — DEFINITION

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Wireless Network Uses radio-wave transmission to communicate at the physical layer

ADVANTAGES OF WIRELESS NETWORKS

Advantage
Easy installation
No cables
Mobility
Public access availability

DISADVANTAGES OF WIRELESS NETWORKS

Disadvantage
Security risks
Bandwidth degradation
Interference
Hardware compatibility issues

EXAM TRAP:
Wireless = less secure by default


TYPES OF WIRELESS NETWORKS


EXTENSION TO WIRED NETWORK

Feature Description
Purpose Extend wired LAN
Device Access Point
Function Bridges wired and wireless

MULTIPLE ACCESS POINTS

Feature Description
Purpose Expand coverage
Requirement Overlapping channels
Benefit Seamless roaming

LAN-TO-LAN WIRELESS NETWORK

Feature Description
Purpose Connect two LANs
Medium Wireless bridge
Complexity High

3G / 4G / 5G HOTSPOT

Feature Description
Source Cellular network
Devices Phones, tablets, laptops
Role Provides Wi-Fi via mobile data

MEMORY HOOK:
Extend → Expand → Bridge → Hotspot


WIRELESS STANDARDS (IEEE 802.11) — CRITICAL


IEEE 802.11 — CORE IDEA

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IEEE 802.11 Wireless LAN standard
Operates 2.4 GHz / 5 GHz

COMMON IEEE 802.11 STANDARDS (TABLE — EXAM FAVORITE)

Standard Frequency Modulation Speed (Mbps) Range (m)
802.11 2.4 DSSS, FHSS 1–2 20–100
802.11a 5 OFDM 6–54 35–100
802.11b 2.4 DSSS 1–11 35–140
802.11g 2.4 OFDM 54 38–140
802.11n 2.4/5 MIMO-OFDM 54–600 70–250

EXTENDED STANDARDS (DO NOT SKIP)

Standard Purpose
802.11i Security (WPA2)
802.11e QoS
802.11h Power control
802.11ac High throughput
802.11ax Wi-Fi 6

MEMORY HOOK (ORDER):
b → a → g → n → ac → ax


SERVICE SET IDENTIFIER (SSID)


SSID — DEFINITION

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SSID Human-readable WLAN name
Nature Logical identifier

SSID BEHAVIOR

Property Detail
Broadcast Enabled by default
Security Provides NO security
Visibility Can be hidden

EXAM TRAP:
Hidden SSID ≠ secure network