OnePopAssignedIp Scenario
This scenario illustrates a configuration that is similar to the OnePopShared scenario. However, the realm for this configuration accommodates situations in which the SAE manages the interface shared by many subscribers but does not directly manage the subscribers. The resolution process takes the subscriber's IP address as the key and returns the reference of the SAE managing this subscriber as the value.
Figure 25 shows the resolution graph for this realm.
The following agents interact with resolvers in this realm:
- Router access agent PoolInterfaceId publishes information about the mappings of IP address pools to interface identifiers from the router.
- Consolidator agent Router publishes information about the routers in the POP.
- SAE plug-in agent InterfaceIdInterface collects information about the mappings of interface identifiers to interface names and responds to resolution requests for this information.
- Directory agent VrSaeId collects and publishes information about the mappings of VRs to SAEs. Because this agent publishes information about all the currently configured VRs, it also provides information about the names of interfaces that a VR manages.
The OnePopAssignedIP scenario provides two host configurations: a centralized configuration and a distributed configuration.
Centralized Configuration
In this configuration, single host DemoHost supports all agents and resolvers. When the NIC proxy sends a subscriber's IP address to host DemoHost, the following sequence of events occurs:
- The host passes the subscriber's IP address to resolver A1.
- Resolver A1 determines the IP pool to which the subscriber's IP address belongs, and passes the IP address to resolver B1.
Resolver A1 must find the most specific IP pool for the IP address. For example, an IP address of 192.9.4.10 belongs to both IP address pools 192.9.0.0/16 and 192.9.4.0/24. The latter pool, however, is the more specific pool for this address.
Consequently, resolver A1 needs to know about all configured IP address pools. If resolver A1 and resolver B1 are on the same host, these resolvers receive the same events, and resolver A1 determines the IP pool information without using resolver B1. If, however, resolvers A1 and B1 are on separate hosts, resolver B1 provides the IP pool information to resolver A1.
- Resolver B1obtains the identifier for the interface associated with the IP pool and returns the interface name to resolver A1.
- Resolver A1 determines the router name directly from the interface identifier and forwards the interface identifier to resolver C1.
In an environment with multiple POPs, resolver A1 uses the router name to determine the POP to which it should forward the request (see AssignedIP Realm in Multiple POPs).
- Resolver C1 obtains an interface name for the interface identifier and returns the interface name to resolver A1.
- Resolver A1 forwards the interface name to resolver D1.
- Resolver D1 obtains a VR name for the interface name and returns the VR name to resolver A1.
- Resolver A1 forwards the VR name to resolver E1.
- Resolver E1 obtains an SAE reference for the VR and returns the SAE reference to resolver A1.
- Resolver A1 passes the SAE reference to its host.
- The host returns the SAE reference to the NIC proxy.
Figure 26 shows the interactions of the NIC components for this realm.
Distributed Configuration
In this configuration, the agents and resolvers are distributed among several hosts. When the NIC proxy sends a subscriber's interface identifier to the host OnePopBO, the resolvers execute the same actions as they do in the centralized configuration. Figure 27 illustrates the interactions of the NIC components for this realm.
AssignedIP Realm in Multiple POPs
To deploy the assignedIP realms in a multiple POP environment, deploy in each POP one set of role C resolvers and the agents InterfaceIdInterface and Router. You can deploy the other resolvers and agents in the back office.
In a multiple POP environment, resolver A determines the POP to which it should send the request based on the router associated with the interface identifier.