TARP/X.500 registration proxy follows SIF TA-9604-034 recommendation (a specification issued by the SONET Interoperability Forum to achieve a convergence of both Directory solutions and to offer an unified Name and Address Resolution Service).
SIF expects TARP/X.500 to behave as a two-way Address-Resolution gateway. From a TARP-only system, it shall be possible to retrieve the Network Address of a NE that is only fitted with a X.500 DUA or another TARP-only system located in a separate island: this function is called "TARP Propagation Proxy". Conversely, a X.500 DUA shall be able to resolve the Network Address of a TARP-only system by only presenting its TID: the second function is named "TARP Registration Proxy".
TARP/X.500 registration proxy provides an implementation of the TARP Registration Proxy which relies on the OSIAM TARP and RA products as depicted below.