Table 13 Q-leaning framework : components and definitions.

From: A hybrid deep learning model for detection and mitigation of DDoS attacks in VANETs

Component

Definition

State (S)

A state s  S represents the current status of the network node, including:

• Traffic load

• Role (e.g., source, relay, sink)

• Message type distribution (CAM, BSM, DENM)

• Local anomaly score

• Recent packet drop rate

Action (A)

An action a  A defines the system’s response, such as:

• Block node

• Throttle bandwidth

• Reroute packets

• Flag and monitor

• No action

Reward (R)

The reward function R(s, a) encourages actions that reduce malicious traffic and maintain QoS:

• + 1 for successfully blocking malicious traffic

• + 0.5 for rerouting that prevents congestion

• − 1 for false positives

• − 2 for failing to block true positives (i.e., letting attacks pass)

Q-Value Update

The Q-values are updated using:

Q(s, a) ← Q(s, a) + α [r + γ max Q(s’, a’) − Q(s, a)]

Where:

• α is the learning rate (0.1)

• γ is the discount factor (0.95)

• s’ is the next state after action a