Timing Covert Channel Simulation

This project simulates a timing covert channel, where a sender transmits a binary message to a receiver without directly sending data. Instead, the communication is done using event timing (sleep intervals) to encode the message. The sender and receiver agree on a start and end signal to encode and decode the message.

Overview of Encoding and Decoding:

• Message Encoding: The message is encoded using two different time intervals:

  • Short Interval (100 ms): Encodes bit '0'.
  • Long Interval (200 ms): Encodes bit '1'.
  • A tolerance of 50 ms is added to accommodate timing inaccuracies.

• Message Decoding:

  • The receiver calculates the time intervals between events to determine whether a '0' or '1' was sent.
  • A timer starts when an event occurs and stops when the next event is detected. The timer's value determines if the received bit is '0' or '1'.
  • The process continues until the end signal of the message is detected.

Implementation Details:

• Sender: Prepares the binary message (e.g., 1381) and transmits it using the agreed intervals.
• Receiver: Listens for the events, calculates the time between them, and reconstructs the binary message based on the intervals.

Multi-threaded Version:

• A more realistic version is implemented using threads, where one thread handles the sending process and another handles the receiving. This version removes the need for start and end signals.
• In this case, the time intervals are modified:
  • Short Interval: 0.5 seconds.
  • Long Interval: 1 second.
  • The tolerance is set to the average of these two values.

Data Exchange Speed:

• The speed of data transmission is based on the intervals:
  • '1' is sent in 200 ms.
  • '0' is sent in 100 ms.
• For a sample message: 11001110101100101001100, the transmission speed is calculated as 0.657 bits per second.

Additional Information:

• The multi-threaded version is available in the repository as TimingCovertChannel.java, which demonstrates synchronized communication between sender and receiver threads using locks to manage timing.

This project offers a practical demonstration of covert channels and timing attacks, showcasing how data can be transferred covertly by manipulating event timing.