Basic Components
This section provides an overview of the basic components that comprise the SDX software.
SAE
The SAE is the core manager of an SDX network. It interacts with other systems, such as Juniper Networks routers, CMTS devices, directories, Web application servers, and RADIUS servers to retrieve and disseminate data in the SDX environment. The SAE authorizes, activates and deactivates, and tracks sessions during which a subscriber is logged in to the network and during which a service is active. The SAE can track more than one service session for a subscriber at a time.
Policy and Service Management
The SAE makes decisions about the deployment of policies on JUNOSe routers and JUNOS routing platforms. When a subscriber's IP interface comes up on the router, the SAE determines whether it manages the interface. If the interface is managed—or controlled by—the SAE, the SAE sends the subscriber's default policy configuration to the router. These default policies define the subscriber's initial network access. When the subscriber activates a value-added service (a service that supplements a subscriber's standard services), the SAE translates the service into lists of policies and sends them to the router. This process lets subscribers manage their own service subscriptions, typically through a Web page.
Accounting Support
The SAE also collects usage information about subscribers and services and passes the information to the appropriate rating and billing system. The SDX software allows a variety of accounting deployments, and provides a standard deployment that incorporates a RADIUS server. You can also create deployments that do not require a RADIUS server.
SAE Extensions
The SAE provides plug-ins and APIs that extend the capabilities of the SDX software. Plug-ins are software programs that augment existing programs and make them more flexible. SDX plug-ins provide authentication, authorization, and tracking capabilities. The SAE APIs let you create customized programs to integrate with the SAE.
SNMP Agent
The SNMP agent monitors system performance and availability, system resources, and SDX processes that are running on the system. The agent obtains information from traps through SNMP and SAE Web Admin. The SNMP agent is preconfigured to monitor SDX processes, such as those associated with infrastructure components (DirX, Interlink RADIUS, and OpenLDAP). Additionally, it provides detailed monitoring and configuration of SDX server components such as the residential and enterprise portals, the SAE, NIC hosts, the policy engine, and the Workflow application.
The master agent determines the SNMP version that supports integration with other network management systems. The SDX SNMP agent runs as a subagent to an installed master agent using the Agent Extensibility (AgentX) protocol. The SDX SNMP agent cannot act as a master agent.
NIC
The NIC collects information about the state of the network and can provide a mapping from a given type of network data, known as a key, to another type of network data, known as a value. A typical use of a NIC is for a portal to submit a subscriber's IP address and for the NIC to return the reference of the SAE that manages the subscriber. The NIC component includes a Web administration application to monitor and inspect the state of NIC servers. Other SDX components such as an enterprise service portal and the sample residential portal use NIC.
Table 7 shows the NIC resolutions that the standard SDX software can perform. For customized software that allows other resolutions, contact Juniper Networks Professional Services.
A NIC comprises a set of software components that work together to collect, process, and provide data. To allow you to design a NIC that performs efficiently for your network configuration, the NIC architecture is highly distributed. This feature means that you can install NIC components in the region of the network that is relevant to the particular functions that those components perform.
For example, in a simple network configuration in which a single office deals with all network traffic, you can install all the NIC components on one workstation. However, in a complex network that supports multiple regions, you might install NIC components in each point of presence (POP) to collect information for that region. The back office, which directs traffic to the different POPs, might also support NIC components that provide information to all POPs.
NIC configurations support redundancy. In a redundant configuration, a pair of NIC hosts or agents form a redundancy community with or without a monitor. The community defines the components that form the redundant relationship, and the monitor tracks the connections between the redundant components.