// Hwang modified version of Neumann Stubblebine 
  
 A, B, S :          principal 
 Na, Ma, Nb, Mb :   number    
 Kas, Kbs, Kab :    key       
 Ta, Tb :           time      
  
  
 1.   A -> B  :   A, Na                                    
 2.   B -> S  :   B, {A, Na, Tb, Nb}Kbs                    
 3.   S -> A  :   {B, Na, Kab, Tb}Kas, {A, Kab, Tb}Kbs, Nb 
 4.   A -> B  :   {A, Kab, Tb}Kbs, {Nb}Kab                 
 5.   A -> B  :   Ma, {A, Kab, Tb}Kbs                      
 6.   B -> A  :   Mb, {Mb}Kab                              
 7.   A -> B  :   {Mb}Kab                                  
   
 // Security Protocols Open Repository 
 // http://www.lsv.ens-cachan.fr/spore 
   
-----------------------------------------------------------------------
  
   
              This document was translated from LaTeX by HeVeA
              (http://pauillac.inria.fr/~maranget/hevea/index.html).