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Security protocols work through the interaction of a number
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of
processes in parallel that send messages to each other.
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CSP is
therefore an obvious notation for describing the
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participants
and their role in the protocol
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Example:
The Yahalom protocol
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Message 1
a g b : a.na
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Message 2
b g s : b.{a.na.nb}ServerKey(b)
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Message 3
s g a : {b. kab.na.nb}ServerKey(a)
.{a.kab}ServerKey(b)
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Message 4
a g b : {a. kab}ServerKey(b) .{nb}kab
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Questions:
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Is the
it based on symmetric or asymmetric cryptography?
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what are na and nb, and what
is their purpose?
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