Definition copy_trans (c : Config) (s1 s2 : Site) :=
  mkconfig (S (time c)) (dt c) (Inc_send_table (st c) s1) 
    (rt c) (Post_message copy (bm c) s1 s2).

Lemma copy_trans_st_rt : forall s0 : Site, s0 <> owner -> access s1 (rt c0) -> ((st c0 s0 > 0)%Z -> rt c0 s0 = true) -> (st (copy_trans c0 s1 s2) s0 > 0)%Z -> rt (copy_trans c0 s1 s2) s0 = true.