Note– Users and groups are designated for the entire Enterprise Server, whereas each
applicationdenes its own roles. When the application is being packaged and deployed, the
applicationspecies mappings between users/groups and roles, as illustrated in the following
gure.
Users
Auseris an individual (or application program) identity that has been dened in the Enterprise
Server.A user can be associated with a group. The Enterprise Server authentication service can
governusers in multiple realms.
Groups
AJavaEE group (or simply group) is a category of users classied by common traits, such as job
titleor customer prole. For example, users of an e-commerce application might belong to the
customergroup, but the big spenders would belong to the preferred group. Categorizing users
intogroups makes it easier to control the access of large numbers of users.
FIGURE9–1 RoleMapping
UnderstandingUsers,Groups, Roles, and Realms
Chapter9 • Conguring Security 105