Authentication in an AD environment

Let's go ahead and revisit our previous example, to see how the authentication process works in an AD environment:

Figure 16.4: Authentication process in AD

The following list summarizes the steps involved in the authentication process:

1. Dave sends the username and his long-term key to the KDC (domain controller).
2. The KDC checks the username and long-term key with its database and verifies the identity. Then, it generates a TGT. It includes a copy of a session key, which the KDC uses to communicate with Dave. This is encrypted using the KDC's long-term key. It also includes a copy of a session key that Dave can use to communicate with the KDC.
3. The KDC responds to Dave with its TGT.
4. Dave decrypts his key using his long-term key and the retrieved session key. His system creates a new request, which includes the TGT and the timestamp encrypted by the session key and service ID. Once the request is...