Locating Subscriber Management Information
For services to be activated for a subscriber session, applications such as the SRC Volume-Tracking Application (SRC VTA), Dynamic Service Activator, Enterprise Manager Portal, or a residential portal need to locate the SAE that manages the subscriber.
The NIC is the component that locates which SAE manages a subscriber or an interface. The NIC uses information that identifies the subscriber or the interface to identify the managing SAE. A NIC is similar to a Domain Name System (DNS) in that a NIC processes resolution requests. Rather than translating hostnames to IP addresses and vice versa, the NIC resolves an identifier for a subscriber or an interface to a reference for the managing SAE.
The components that participate in this resolution are a NIC host and a NIC proxy, also called a NIC locator for particular applications. A NIC host processes resolution requests. A NIC proxy requests data resolution for an application. A NIC proxy is so-named because it requests information on behalf of an application. A NIC proxy and a NIC host communicate with each other through Common Object Request Broker Architecture (CORBA); NIC manages the CORBA interactions for you.
NIC can operate in a client/server mode or in a local host mode. In the client/server mode, a NIC host and NIC proxies can reside on different systems. In local host mode, a NIC host and NIC proxies reside in the same process on a machine.
NIC Client/Server Mode
In client/server mode, a NIC host is the server. A NIC proxy, which comprises libraries within an application that interacts with a NIC host, is the client.
Figure 1 shows a NIC proxy running within an application and a NIC host running on a different machine. Both communicate through CORBA, with the NIC proxy providing an identifier for a subscriber and the NIC host returning a reference to the SAE that manages the subscriber.
NIC Local Host Mode
In local host mode, a Java application can include the libraries for a NIC host as well as NIC proxies. With this configuration, the NIC host and the NIC proxies communicate with each other within the same application. Because both components run within the same application, the application and the NIC host start and stop at the same time.
If an application uses a local NIC host, all NIC proxies for the application typically communicate with the local NIC host, but some of the NIC proxies can be configured to communicate with a NIC host that runs on another system.
When you use NIC in local host mode:
You cannot use the C-Web interface to monitor or troubleshoot the local NIC host
The NIC host runs all the resolvers and agents for the host on the local machine.
Other NIC hosts cannot communicate with agents and resolvers that run in a local NIC host.
Figure 2 shows a NIC proxy and a NIC host running within an application.