Fine-Grained Access to Network Services in Oracle Database 11g R1(原创)

Overview
Oracle allows access to external network services using several PL/SQL APIs (UTL_TCP, UTL_SMTP, UTL_MAIL, UTL_HTTP and UTL_INADDR), all of which are implemented using the TCP protocol. In previous versions of the database, access to external services was effectively an on/off switch based on whether a user was granted execute permissions on a specific package or not. Oracle 11g introduces fine grained access to network services using access control lists (ACL) in the XML DB repository, allowing control over which users access which network resources, regardless of package grants.  Access control lists can be created, amended and deleted in the XML DB repository directly using FTP or WebDav. In addition, Oracle provide the DBMS_NETWORK_ACL_ADMIN and DBMS_NETWORK_ACL_UTILITY packages to allow ACL management from PL/SQL.Oracle allows access to external network s