Network security for Adaptive Server is achieved through the security control layer (SCL). The security features supported by Adaptive Server are provided by one or more of the security drivers that work with a particular security mechanism.
Releases of Adaptive Server earlier than 12 could obtain network service information only by reading the interfaces file in the Sybase release directory. Adaptive Server 12 can access network service information, such as the host name and port number, from sources other than the interfaces file. Adaptive Server sends and receives this configuration information through the directory control layer (DCL), which defines a generic directory service for applications to access the network service information.
The drivers for specific service providers are called directory drivers. If no directory drivers are installed, the DCL obtains network services information from the interfaces file. Directory drivers are platform-specific. For example, the DCE directory driver is implemented on several UNIX platforms, but the NT Registry driver is implemented only on the NT platform.
