A Mechanically Proved and an Incremental Development of the Session Initiation Protocol INVITE Transaction

Algorithm 1

Events of initial model.

  client_Send 

ANY

   msg

WHERE

   grd4: msg REQUESTS

   grd3: msg cl_sent

THEN

   act6: cl_sent cl_sent   {msg}

END

  server_Receive 

ANY

   msg

WHERE

   grd5: msg REQUESTS

   grd6: msg cl_sent

THEN

   act5: sr_got sr_got   {msg}

END

  server_send 

ANY

   msg

WHERE

   grd1: msg RESPONSES

   grd2: msg sr_sent

   grd3: sr_got  

THEN

   act2: sr_sent sr_sent  {msg}

END

  client_Receive 

ANY

   msg

WHERE

   grd5: msg RESPONSES

   grd6: msg sr_sent

THEN

   act5: cl_got cl_got   {msg}

END