Figure 1-1 shows an IP connection between two routers riding over an optical network.
In the IP domain, the logical connection exists between two interfaces, but the underlying optical network is unknown to the IP Domain Manager. The NetworkConnection element is discovered and managed by IP Manager.
In the Optical domain, the Circuit traversing the network (shown in bold) is managed by an OTM Domain Manager, but its purpose, and therefore impact, in the IP domain is unknown. The Circuit element is managed by Optical Transport Manager.
Just as failures in the Optical domain may result in symptoms in the IP domain, failures in the IP domain may result in symptoms in the Optical domain. The XD Manager OTM to IP correlates failures in the Optical and IP domains to determine the actual root cause and associate the root cause to the impacts in other domains.