343.1—Definitions.
         For purposes of this part, the following definitions apply:
    
    
        
        (a) 
        
            Complaint means a filing challenging an existing rate or practice under  section 13(1) of the Interstate Commerce Act.
    
    
        
        (b) 
        
            Protest means a filing, under  section 15(7) of the Interstate Commerce Act, challenging a tariff publication.