This is an example of a MAN aggregation network. MANs are responsible for aggregating all access traffic in a metropolitan (or rural) region and to deliver it to the providers of core network POPs. They also deliver traffic of the provider’s core POPs in a certain region to the deployed access networks. MANs also provide a set of interconnection services directly to high-end customers (enterprises). This done by traffic segmentation and efficient resource allocation to maximise network utilisation while proving the promised QoS to customers.

The DIF structure of this network is a minimalistic version of a MAN segment. Multiple Metro Service DIFs realise the traffic segmentation, providing different instances of IPC for MAN services, for instance point-to-point (E-Line), multipoint-to-multipoint (E-LAN) or rooted multipoint (E-Tree). Traffic from these service instances is aggregated over the Metro Backbone DIF. This DIF transports traffic over the MAN providing adequate QoS differentiation, performance isolation, and traffic engineering.