[Casimiro Notevi]

Con Interbase no sé, con Firebird lo puedes obtener con 'CLIENT_ADDRESS', aquí tienes un ejemplo que devuelve la IP y otros parámetros:

Código SQL [-]
SELECT RDB$GET_CONTEXT('SYSTEM', 'ENGINE_VERSION') AS engineversion,
       RDB$GET_CONTEXT('SYSTEM', 'NETWORK_PROTOCOL') AS protocol,
       RDB$GET_CONTEXT('SYSTEM', 'CLIENT_ADDRESS') AS address,
       RDB$GET_CONTEXT('SYSTEM', 'DB_NAME') AS dbname,
       RDB$GET_CONTEXT('SYSTEM', 'SESSION_ID') AS sesionid,
       RDB$GET_CONTEXT('SYSTEM', 'TRANSACTION_ID') AS transactionid,
       RDB$GET_CONTEXT('SYSTEM', 'CURRENT_USER') AS currentuser
FROM RDB$DATABASE;