For the SNMP DPI 2.0 API, some functions are implemented as macros, because the older DPI Version 1.x had the same function names with different parameters. The new implementation has new function names, which are not always the most intuitive. By defining the macros with the more natural names for the functions, the non-intuitive names are hidden. This was done because the macros have the same names as the functions were named in DPI Version 1. It is thus possible to provide either the DPI 1.x or the DPI 2.x API by properly defining the macros.