Application Scenarios for NAT444
This section describes NAT444 application scenarios.
Figure 1 shows the NAT444 application scenario.
- The CPE is a user access device that assigns private IPv4 addresses and performs first NAT for service flows.
- The Broadband Remote Access Server (BRAS), a MAN device at the access layer, is embedded with a DHCP Server module and works as a RADIUS client with the AAA server for CPE authentication and address allocation. The BRAS device in NAT444 scenarios assigns IPv4 addresses to the CPE, and the CPE uses these addresses for communication with the CGN device.
- The CGN device is a traffic aggregation device that performs secondary NAT for CPE traffic, enabling a private IPv4 user to access the Internet.
