Digest Authentication combines Basic Authentication with MD5 encryption, thus avoiding the transmission of plain text passwords, making for a more secure login method over plain HTTP.
On its own, Digest Authentication is still insecure without an SSL/TLS-secured HTTPS connection. Anything over plain HTTP is vulnerable to man in the middle attacks, where an adversary can intercept requests and forge responses. An attacker could masquerade as the server, replacing the expected Digest response with a Basic Authentication response, thus gaining the password in plain text.
Nevertheless, in the absence of SSL/TLS, Digest Authentication at least affords us some defense in the area of plain text passwords requiring more advanced circumvention techniques.
So in this recipe, we will create a Digest Authentication server.