w2 Securing the Internet of Things - Lecture 1: The Ten Security Principles & Smart Home Privacy

This set of vocabulary flashcards covers the ten fundamental security design principles and the concepts surrounding smart home privacy, traffic analysis attacks, and defensive techniques such as Stochastic Traffic Padding.

Economy of Mechanism

The principle that security systems should be as simple as possible in their design and implementation, as simplicity makes systems easier to test, verify, and less likely to hide bugs/vulnerabilities.

Fail-Safe Defaults

The principle that the default configuration of any system should deny access, and the system should fail in a secure, locked state rather than an open one.

Complete Mediation

The principle that every request to access a resource must be checked against security rules every single time, rather than assuming past approval still applies.

Open Design

The principle that a system's security should rely on keeping keys and passwords secret, rather than keeping the design or algorithm of the system secret.

Separation of Privilege

The principle that access to sensitive resources should require meeting multiple conditions or checks, such as multi-factor authentication, to prevent a single compromised check from granting entry.

Least Privilege

The principle of giving a user, program, or device only the minimum permissions necessary to perform its task and nothing more.

Least Common Mechanism

The principle of minimizing shared resources, paths, or interfaces between users to reduce the risk of one user's compromised access affecting others.

Usable Security (Psychological Acceptability)

The principle that security interfaces must be intuitive and easy to use correctly, otherwise users will bypass or disable them.

Work Factor

The principle of matching the strength and cost of security to the value of the asset being protected and the resources of likely attackers.

Compromise Recording

The principle of maintaining logs and monitoring to detect and understand security breaches when prevention is not possible or fails.

Traffic Analysis

A privacy threat where an observer determines a user's private activities by watching network traffic timing, volume, and patterns, even if the data is encrypted.

Local Adversaries

Attackers near a home, such as neighbors, who can observe WiFi signals, MAC addresses, packet sizes, and timing of IoT traffic.

External Adversaries

Attackers on the internet, such as ISPs or intelligence agencies, who see the times, sizes, and IP headers of all traffic leaving a home router.

Stochastic Traffic Padding (STP)

A traffic shaping technique that protects privacy by randomly inserting fake traffic bursts that look like real device activity to hide actual usage patterns.

Independent Link Padding (ILP)

A privacy defense that forces devices to send data at a constant rate, adding fake data when idle, which provides excellent protection but wastes significant bandwidth.

VPN (Virtual Private Network)

A defense that wraps all traffic in an encrypted tunnel to a remote server, hiding individual device details from external observers while traffic volume changes remain potentially visible.

Attacker Confidence

A measure of how often an attacker correctly guesses whether a traffic burst represents real activity or fake padding; at $50 \%$ confidence, the analysis is no better than a coin flip.

AES (Advanced Encryption Standard)

A public encryption algorithm that follows the Open Design principle and remains unbroken because its security depends on the key rather than the algorithm's secrecy.

KeeLoq

A proprietary encryption system used in car key fobs that was broken within two years of researchers uncovering its secret algorithm, illustrating the failure of security by obscurity.

MAC Address

A unique identifier for specific devices that is visible to local adversaries watching WiFi signals, even when traffic content is encrypted.

DNS Lookup

An observation of which domain a device is visiting; local and external adversaries use this to identify the brand or type of smart device communicating.

What is the principle of Economy of Mechanism?

The principle that security systems should be as simple as possible in their design and implementation, as simplicity makes systems easier to test, verify, and less likely to hide bugs/vulnerabilities.

Explain Fail-Safe Defaults in security systems.

The principle that the default configuration of any system should deny access, and the system should fail in a secure, locked state rather than an open one.

Define Complete Mediation in the context of security.

The principle that every request to access a resource must be checked against security rules every single time, rather than assuming past approval still applies.

What does Open Design entail in security systems?

The principle that a system's security should rely on keeping keys and passwords secret, rather than keeping the design or algorithm of the system secret.

What is the Separation of Privilege principle?

The principle that access to sensitive resources should require meeting multiple conditions or checks, such as multi-factor authentication, to prevent a single compromised check from granting entry.

Can you explain the Least Privilege principle?

The principle of giving a user, program, or device only the minimum permissions necessary to perform its task and nothing more.

What does the Least Common Mechanism principle propose?

The principle of minimizing shared resources, paths, or interfaces between users to reduce the risk of one user's compromised access affecting others.

Describe Usable Security (Psychological Acceptability).

The principle that security interfaces must be intuitive and easy to use correctly, otherwise users will bypass or disable them.

How does Work Factor define security measures?

The principle of matching the strength and cost of security to the value of the asset being protected and the resources of likely attackers.

What is the significance of Compromise Recording in security?

The principle of maintaining logs and monitoring to detect and understand security breaches when prevention is not possible or fails.