The registrar is responsible for developing the client application that will interface with the registry using the EPP protocol. The .aero registrar toolkit (RTK) is available to any interested party that would like to develop registrar client applications. A registrar may opt to develop their application to conform to the EPP specification without the use of the RTK. This is acceptable as long as the client is able to pass the OT&E certification process.

The registry-registrar communication channel will be encrypted. An SSL certificate from an approved certificate authority is required to establish this encrypted channel. The registrar is responsible for acquiring the SSL certificate and developing support for SSL in their client application. Please see the Security FAQ for details.