BNG Role in ISP Network Models
The DSLAM modifies the DHCP packets by inserting subscriber identification information. BNG uses the
identification information inserted by the DSLAM, as well as the address assigned by the DHCP server, to
identify the subscriber on the network, and monitor the IP address lease.
BNG Role in ISP Network Models
The role of BNG is to pass traffic from the subscriber to the ISP. The manner in which BNG connects to the
ISP depends on the model of the network in which it is present. There are two types of network models:
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•
Network Service Provider
The following figure shows the topology of a Network Service Provider model.
Figure 2: Network Service Provider Model
In the Network Service Provider model, the ISP (also called the retailer) directly provides the broadband
connection to the subscriber. As shown in the above figure, BNG is at the edge router, and its role is to connect
to the core network through uplinks.
Cisco ASR 9000 Series Aggregation Services Router Broadband Network Gateway Configuration Guide,
Release 4.2.x
4
Network Service Provider, on page 4
Access Network Provider, on page 5
Broadband Network Gateway Overview
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