Formal Modelling of PBFT Consensus Algorithm in Event-B

Listing 19

Event ‘view_change’.

 Event view_change

  Anysend rec

  Where

  @grd1 pre∈NODES

  @grd2 pre∈crash

  @grd3 send∈NODES

  @grd4 rec∈NODES

  @grd5 send≠rec

  @grd6 send≠pre∧rec≠pre

  Then

  @act1

View_change(rec)≔View_change(rec)<+{send↦max(NODES∖Pre_set)}

 End