Do not use the default authentication token in service provider code. This default token is used by the WebSphere Application Server run-time code only and is authentication mechanism specific.
Any modifications to this token by service provider code can potentially cause interoperability problems. If you need to create an authentication token for custom usage, see Implementing a custom authentication token for more information.
The com.ibm.ws.security.ltpa.LTPATokenFactory token factory is the default for this property. The LTPATokenFactory token factory uses the DESede/ECB/PKCS5Padding cipher. This token factory creates an interoperable Lightweight Third Party Authentication (LTPA) token. If you change this token factory, you lose the interoperability with any servers running a version of WebSphere Application Server prior to Version 5.1.1 and any other servers that do not support the new token factory implementation. However, if all of your application servers use WebSphere Application Server Version 5.1.1 or later and all of your servers use your new token factory, this interoperability is not a problem.
If you associate the com.ibm.ws.security.ltpa.LTPAToken2Factory token factory with the com.ibm.wsspi.security.token.authenticationTokenFactory property, the token is Advanced Encryption Standard (AES) encrypted. However, you need to weigh the performance against your security needs. You might add additional attributes to the authentication token in the Subject during a login that are available downstream.