NonStop Servlets for JavaServer Pages (NSJSP) 6.1 System Administrator's Guide

Security Considerations
NonStop Servlets for JavaServer Pages (NSJSP) 6.1 System Administrator’s Guide—596210-006
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Realms
application resources is granted to all users possessing a particular role. There can be
any number of roles associated with a username.
In many cases, however, it is desirable to connect a servlet container to an existing
authentication database or an existing authentication mechanism. Therefore, NSJSP
defines a Java interface (org.apache.catalina.Realm) that can be implemented
by plug in components to establish a connection for authentication.
The following plug-in components support connections to various sources of
authentication information:

MemoryRealm: Accesses authentication information stored in an in-memory object
collection, which is initialized from an XML document
(<NSJSP_HOME>/conf/nsjsp-users.xml).

JDBCRealm: Accesses authentication information stored in a relational database,
accessed using a Java Database Connectivity (JDBC) driver.

DataSourceRealm: Accesses authentication information stored in a relational
database, accessed using a Java Naming and Directory Interface (JNDI) named
JDBC DataSource.

JNDIRealm: Accesses authentication information stored in the Lightweight
Directory Access Protocol (LDAP) accessible directory server, accessed using a
JNDI provider.

UserDatabaseRealm: Accesses authentication information stored in a JNDI
resource, which is an XML file by default.

JAASRealm: Accesses authentication information through the Java Authentication
and Authorization Service (JAAS) framework.
Apart from these standard plug-in components, NSJSPLockoutRealm and
CombinedRealm are other implementations, (that also implement the Realm interface)
which provide the Realm functionality by using one or more of the previously
mentioned plug-ins.
Realm elements can be configured as child elements of any of the following elements:

The Engine element: The Engine element is defined in the
<NSJSP_HOME>/conf/server.xml file. In this case, the Realm applies to all
contexts (web applications) in all the Hosts configured under the Engine element.
Any Realm definition in the Host or Context element overrides the Realm
definition in the Engine element. In the default NSJSP configuration, a
UserDatabaseRealm is configured under the Engine element and is used to
authenticate users in the Admin and the Manager Web applications.

The Host element: Host elements are defined in the
<NSJSP_HOME>/conf/server.xml file. This Realm definition applies to all
Note. The Java Servlet specification defines declarative elements, such as security-
constraint, auth-constraint, user-data-constraint as part of the deployment
descriptor to define an application's security requirements.