Message layer authentication

Defines the credential information and sends that information across the network so that a receiving server can interpret it.

When you send authentication information across the network using a token the transmission is considered message layer authentication because the data is sent with the message inside a service context.

A pure Java™ client uses Kerberos (KRB5) or basic authentication, or Generic Security Services Username (GSSUP), as the authentication mechanism to establish client identity.

However, a servlet can use either basic authentication (GSSUP) or the authentication mechanism of the server, Kerberos (KRB5) or LTPA, to send security information in the message layer. Use KRB5 or LTPA by authenticating or by mapping the basic authentication credentials to the security mechanism of the server.

The security token contained in a token-based credential is authentication mechanism-specific. The way that the token is interpreted is only known by the authentication mechanism. Therefore, each authentication mechanism has an object ID (OID) representing it. The OID and the client token are sent to the server, so that the server knows which mechanism to use when reading and validating the token.

The following list contains the OIDs for each mechanism:

BasicAuth (GSSUP):  oid:
KRB5: OID: 1.2.840.113554.1.2.2
LTPA:    oid:
SWAM:     No OID because it is not forwardable

SWAM is deprecated in WAS V7.0 and will be removed in a future release.

On the server, the authentication mechanisms can interpret the token and create a credential, or they can authenticate basic authentication data from the client, and create a credential. Either way, the created credential is the received credential that the authorization check uses to determine if the user has access to invoke the method. We can specify the authentication mechanism by using the following property on the client side:

Basic authentication (BasicAuth) and KRB5 are currently the only valid values. Configure the server through the admin console.

When perform basic authentication is enabled, if the client is not similarly configured (and does not pass a credential such as a user ID and password).


Configuring authentication retries

Situations occur where you want a prompt to display again if we entered the user ID and password incorrectly or you want a method to retry when a particular error occurs back at the client. If we can correct the error by information at the client side, the system automatically performs a retry without the client seeing the failure, if the system is configured appropriately. Some of these errors include:

By default, authentication retries are enabled and perform three retries before returning the error to the client. Use the property (True or False) to enable or disable authentication retries. Use the property to specify the number of retry attempts.


Immediate validating of a basic authentication login

In WAS V6.x, a behavior is defined during request_login for a BasicAuth login. In releases prior to V5, a BasicAuth login takes the user ID and password entered through the loginSource method and creates a BasicAuth credential. If either the user ID or the password is not valid, the client program does not find out until the first method request is attempted. When the user ID or password is specified during a prompt or programmatic login, the user ID and password are authenticated by default with the security server, with a True or False returned as the result.

If False, an org.omg.SecurityLevel2.LoginFailed exception is returned to the client indicating that the user ID and password are not valid. If True, then the BasicAuth credential is returned to the caller of the request_login. To disable this feature on the pure client, specify

By default, this feature is set to True. On the server side, specify this property in the security dynamic properties.

Set whenever connecting to a z/OS server. This function does not currently work from a distributed client to a z/OS server since the SecurityServer is located using the "UNAUTHENTICATED" principal, which is not accepted on a z/OS system.


Related tasks

Secure communications
Select an authentication mechanism