Существует четыре настраиваемые точки ведения журнала для сообщения: ServiceLevelSendRequest, TransportSend, TransportReceive, ServiceLevelReceiveRequest.
Service Level : At this level the message is logged when it is about to leave or enter the code. Secure messages are logged decrypted at this level.
Transport Level : At this level messages are logged just before getting encoded or after getting decoded for transmission over wire. Even reliable messaging messages are logged.
Malformed Level : All the messages which WCF fails to process due to improper format gets logged.