Formal Modelling of PBFT Consensus Algorithm in Event-B

Listing 13

Event ‘request’.

Event request

 Refines request

  Anym1 m2

  Where

   @grd1 m1∈message

   @grd2 m2∈ℕ×value

   @grd3 m2=contents(m1)

   @grd4 m1∉cache(pre)

   @grd5 prj1(m2)=max(dom(contents[cache(pre)]))+1

   @grd6 prj1(m2)−n∈1‥H

   @grd7 prj2(m2)∉ran(contents[cache(pre)])

  With

   @mm=m1

  Then

   @act1 cache≔cache<+{pre↦cache(pre) ∪ {m1}}

End