Govroam

The correct format for the CSI (called/calling station ID) is explained in RFC3580: uppercase and hyphen separated.

This code snipped for FreeRADIUS will capitalise and format correctly:

rewrite_calling_station_id {                                                            
      if (Calling-Station-Id =~/([0-9a-f]{2})[-:]?([0-9a-f]{2})[-:.]?([0-9a-f]{2})[-:]?([0-9a-f]{2})[-:.]?([0-9a-f]{2})[-:]?([0-9a-f]{2})/i) {                                                                   
              update request {                                                          
                      Calling-Station-Id := "%{toupper:%{1}-%{2}-%{3}-%{4}-%{5}-%{6}}"  
              }                                                                         
      } else {                                                                          
              noop                                                                      
      }                                                                                 
}                                                                                       

Thanks to Matt Richards from Bath University for writing and sharing this code.