|  | 1 | 
            
              | Message sender |  
              | Identifies the party which generates the security parameters of the message (i.e. security originator). |  | 
        
          |  | 2 | 
            
              | Message receiver |  
              | Identifies the party which verifies the security parameters of the message (i.e. security recipient). |  | 
        
          |  | 3 | 
            
              | Certificate owner |  
              | Identifies the party which owns the certificate. |  | 
        
          |  | 4 | 
            
              | Authenticating party |  
              | Party which certifies that the document (i.e. the certificate) is authentic. |  |