# Package org.apache.hc.client5.http.impl.auth

Standard and common HTTP authentication schemes.

See: Description

Interface Summary
NTLMEngine: Abstract NTLM authentication engine.

Class Summary
AuthCacheKeeper: Utility class that implements commons aspects of the client side authentication cache keeping.
AuthChallengeParser: Authentication challenge parser.
AuthSchemeSupport
BasicAuthCache: Default implementation of `AuthCache`.
BasicCredentialsProvider: Default implementation of `CredentialsStore`.
BasicScheme: Basic authentication scheme as defined in RFC 2617.
BasicSchemeFactory: `AuthSchemeFactory` implementation that creates and initializes `BasicScheme` instances.
CredentialsProviderBuilder: `CredentialsProvider` builder.
DigestScheme: Digest authentication scheme as defined in RFC 2617.
DigestSchemeFactory: `AuthSchemeFactory` implementation that creates and initializes `DigestScheme` instances.
GGSSchemeBase: Common behavior for `GSS` based authentication schemes.
HttpAuthenticator: Utility class that implements commons aspects of the client side HTTP authentication.
KerberosScheme: Kerberos authentication scheme.
KerberosSchemeFactory: `AuthSchemeFactory` implementation that creates and initializes `KerberosScheme` instances.
NTLMScheme: NTLM is a proprietary authentication scheme developed by Microsoft and optimized for Windows platforms.
NTLMSchemeFactory: `AuthSchemeFactory` implementation that creates and initializes `NTLMScheme` instances configured to use the default `NTLMEngine` implementation.
SPNegoScheme: SPNEGO (Simple and Protected GSSAPI Negotiation Mechanism) authentication scheme.
SPNegoSchemeFactory: `AuthSchemeFactory` implementation that creates and initializes `SPNegoScheme` instances.
SystemDefaultCredentialsProvider: Implementation of `CredentialsStore` backed by standard JRE `Authenticator`.

Exception Summary
NTLMEngineException: Signals NTLM protocol failure.
UnsupportedDigestAlgorithmException: Authentication credentials required to respond to a authentication challenge are invalid

## Package org.apache.hc.client5.http.impl.auth Description

Standard and common HTTP authentication schemes.