equal
deleted
inserted
replaced
47 \end{center} |
47 \end{center} |
48 |
48 |
49 Write down three facts that $A$ can infer after this protocol has been |
49 Write down three facts that $A$ can infer after this protocol has been |
50 successfully completed? |
50 successfully completed? |
51 |
51 |
52 \item (\textbf{Deleted}: same as 2) Before starting a TCP connection, client and servers |
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53 perform a three-way handshake: |
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54 |
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55 \begin{center} |
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56 \begin{tabular}{rl} |
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57 $A \rightarrow S$: & SYN\\ |
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58 $S \rightarrow A$: & SYN-ACK\\ |
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59 $A \rightarrow S$: & ACK\\ |
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60 \end{tabular} |
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61 \end{center} |
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62 |
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63 How can this protocol be abused causing trouble on the server? |
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64 |
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65 \item Write down a protocol which establishes a secret key |
52 \item Write down a protocol which establishes a secret key |
66 between $A$ and $B$ using a mutually trusted third party $S$. |
53 between $A$ and $B$ using a mutually trusted third party $S$. |
67 You can assume $A$ and $S$, respectfully $B$ and $S$, share |
54 You can assume $A$ and $S$, respectfully $B$ and $S$, share |
68 secret keys. |
55 secret keys. |
69 |
56 |