Game description in battleship 1

Game description in battleship 1 150 150 Affordable Capstone Projects Written from Scratch

Assignment 1


Alice and Bob would like to play Battleship1 over the Internet. In the version of the

game used in this assignment, Alice and Bob place the following ships on a 10 × 10 grid:

  • One aircraft carrier (length 5)
  • One battleship (length 4)
  • One cruiser (length 3)
  • One submarine (length 3)
  • One destroyer (length 2)

The players do not trust each other, and they will try to cheat given the opportunity.

Further, the players cannot agree on a trusted server to store the position of the ships,

and disclose hits when they occur. For this reason, they decide to build a software that

allows them to play securely in a decentralized manner. The software must detect and

report cheating, and must output a proof of the other user’s cheating when it occurs. If

Alice decides to cheat, she can make arbitrary modifications to her local copy of the game

(for instance, you can assume that the players are given the source code of the Battleship

software, and that they are expert programmers).

Write a three-page report which includes the following sections:

  1. Introduction: describe the general idea of how you are planning to implement the

game, and why it leads to a secure implementation of the game.

  1. Protocol description: show a diagram detailing all messages exchanged during the

game. For each message, specify as many details as necessary, including whether

a message is encrypted, authenticated, which keys are used, etc. Feel free to use

pseudo-code, if needed. Also include messages exchanged between Alice and Bob

before the game starts, if any.

  1. Security Arguments: show why the protocol is secure against meaningful attacks.


  1. References: any reference you used, if any.

The Battleship software is only concerned with cheating that involves actions such

as moving the ships to avoid hits after the game has started, learning about the ships

location without firing shots, and not reporting hits. Any other cheating (e.g., hacking

into the computer of one of the parties, or asking help for the next move over the Internet)

are out of scope.

You can assume that Alice and Bob met over some other medium (e.g., an online

forum), and have already exchanged identifiers that can be used by the game (e.g., their

respective IP addresses). These interactions can be omitted from your report. You can

also assume that neither party will implement a DoS attack against the other player, and

that both parties will continue playing until one of them wins.