// herman's self stabilising algorithm [Her90] // gxn/dxp 13/07/02 // the procotol is synchronous with no non-determinism (a DTMC) dtmc // module for process 1 module process1 // Boolean variable for process 1 x1 : [0..1]; [step] (x1=x7) -> 0.5 : (x1'=0) + 0.5 : (x1'=1); [step] !(x1=x7) -> (x1'=x7); endmodule // add further processes through renaming module process2 = process1[x1=x2, x7=x1 ] endmodule module process3 = process1[x1=x3, x7=x2 ] endmodule module process4 = process1[x1=x4, x7=x3 ] endmodule module process5 = process1[x1=x5, x7=x4 ] endmodule module process6 = process1[x1=x6, x7=x5 ] endmodule module process7 = process1[x1=x7, x7=x6 ] endmodule // cost - 1 in each state (expected steps) rewards true : 1; endrewards // any initial state (consider any possible initial configuration of tokens) init true endinit