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In terms of Process Algebra. Process P:. 4. m. a. 1. 2. 5. m. a. box P var -- program counter action a :: {1,2} := +1 action b :: =3 :=1 method m ::. b. m. 3. Properties. Process P:. 4. m. a. 1. 2. 5. m. a. m. 3.
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In terms of Process Algebra Process P: 4 m a 1 2 5 m a box P var -- program counter action a :: {1,2} := +1 action b :: =3 :=1 method m :: ... b m 3
Properties Process P: 4 m a 1 2 5 m a m 3 Safety : constraints relating current and next state, e.g. = 1 unless = 2 {4,5} unless false Progress, e.g. = 1 {4,5}
x x [] 2 Parallel Composition 4 m a 1 2 5 m a m 3
x Properties under Parallel Composition 4 m a 1 2 5 m a m 3 These safety are preserved: = 1 unless = 2 {4,5} unless false Progress: = 1 {4,5} destroyed!
Preserved if we assume strong fairness. Properties under Parallel Composition 4 m a 1 2 5 m m 3 Progress: = 1 {4,5} Preserved if we assume weak fairness.