Definition server_send_trans :=
  SendTrans ss_safe_coh ss_safe_in ss_safe_def ss_step_coh.

(* Specifications: *)
Lemma cs_safe_coh this to d m : cs_safe this to d m -> coh d.
Lemma cs_step_coh : s_step_coh_t coh req cs_step.
Lemma cs_safe_def this to d msg : cs_safe this to d msg <-> exists b pf, @cs_step this to d msg pf = Some b.