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By February 1, 2021No Comments

EE6032-ED5012 Assignment – Worth 40% of module Given the Covid-19 virus and the problem that poses with group coding projects I have decided to use this assignment in place of the usual project. Note: This assignment can be completed individually or in groups of two (no more than two allowed). Assignment Details: Design a security protocol that will allow a Mutually Agreed Session key (Kabc) to be established between three entities A, B and C. This key can then be used to secure a chat between the three entities. I want you to develop your own design based on the conditions below. Note: The session key should NOT be known to the Chat Server (S) and the Chat Server (S) can only forward the encrypted messages to A, B and C and S cannot read the messages. The secure chat between entities A, B and C must use the Chat Server (S) and session key Kabc as below: i.e. A, B and C Do NOT communicate directly. The following conditions apply to your protocol design. 1. A, B and C Never communicate directly. 2. Each entity (A, B, C and S) have a Public Key Certificate, ie. CA<>, CA<>, CA<> and CA<>. 3. The Chat Server, S, has access to all Entity Certificates that use its service and can provide these Certificate to its service users if requested to do so. 4. Challenge – Response process is to be used to establish freshness of communications between A, B and C. 5. Each step in establishing the Session key (Kabc) must provide an Authenticated Integrity check of the data transferred. You must show both sides of this in your protocol description, i.e. its generation and how it is checked. 6. Each Entity must Authenticate itself to the Server S before it is allowed to use its service. 7. For each of the steps where you use CIA (Confidentiality, Integrity or Authentication) please state the algorithm you would use to perform that function. This is to be provided in the description you will provide for the protocol. You must provide a legend to describe your notation and a full description of each step in the protocol that is used to establish the shared key Kabc. Chat Server (S) A B {M1}Kabc {M2}Kabc {M2}Kabc {M1}Kabc C {M1}Kabc {M3}Kabc {M3}Kabc {M3}Kabc {M2}Kabc Grading Details This will be graded as follows: A protocol diagram and a full description of each step in the protocol is required. This is to include suitable notation and a text description of each step. Your description must clearly show and describe where/how the following is provided for 30% of the marks. Mutual Agreed Key setup: 10% Integrity: 10% Confidentiality/Authentication: 10% A high quality and professionally structured document is allocated 10% Quality of protocol, Steps, description: 5% Quality/Structure of submitted Document: 5% 欢迎咨询51作业君


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