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All productsHUAWEI-CGN-MIB is used to query data of value-added services. The data includes the NAT instance configuration, license configuration, user address pool, port usage, tunnel usage, device forwarding capability, current number of sessions, and statistics on static NAT.
CGN reliability allows proper traffic forwarding without letting users perceive faults and save resources for users.
Currently, IPv4 address shortage is an extremely serious problem and has become an insurmountable obstacle for the rapid growth of Internet, especially in mobile broadband and Internet of things (IoT). The most significant advantage of IPv6 is that IPv6 quadruples the number of network address bits from 32 bits in IPv4 to 128 bits, providing more than enough globally unique IP addresses for every networked device on the planet, addressing the fundamental issue of IPv4 address exhaustion. However, because mass IPv4 services are still carried on the Internet, service providers cannot transform their existing IPv4 networks to IPv6-only networks in a short time. A solution is to enable IPv6 offerings while continuing to use the existing IPv4 infrastructures. As IPv6 offerings become more and more popular, service providers can gradually upgrade their infrastructures to IPv6. This means that IPv4 and IPv6 will coexist for some time during the transition from IPv4 to IPv6.
Traditionally NAT is in most cases deployed on user-side CPEs to implement address translation for a small number of users. Carrier grade NAT (CGN) is deployed on carrier networks to implement address translation for a large number of users. Therefore, CGN outperforms traditional NAT in terms of capacity, performance, and reliability.
- Functionally, CGN implements translation between addresses, such as translation between private IPv4 addresses, between a private IPv4 address and a public IPv4 address, and between an IPv4 address and an IPv6 address. Some CGN technologies also provide tunnel functions.
- CGN functions can be provided by either a standalone CGN device or a CGN board. If you insert a CGN board into a BRAS, the BRAS will be able to provide both access and CGN functions.
If multiple VSUF-80/VSUF-160/VSUI-160-Es are installed on a NAT64 device, the service boards can be configured to work in master/backup mode in the same chassis to implement inter-board backup. The inter-board backup mechanism ensures that the data stored in the CPUs of the master and slave service boards is consistent. If the master service board fails, an inter-board master/slave switchover is performed to ensure that services run properly. In this situation, services are properly transmitted, and users are unaware of the fault.
- If a NAT64 device has slots for two or more VSUF-80/VSUF-160/VSUI-160-Es and provides access services for a small number of users, you can apply inter-board 1:1 backup. In inter-chassis 1:1 backup, when the service board on the master device processes services, the service board on the backup device does not work. The service board on the master device backs up the user tables, session tables, and address pool entries to the service board on the backup device. Once the master service board fails, the slave service board takes over services.
- If a NAT64 device has slots for two or moreVSUF-80/VSUF-160/VSUI-160-Es and provides access services for a large number of users, you can apply inter-board 1+1 backup. In inter-board 1+1 backup, both the master and backup service boards process services and back up their user tables, session tables, and address pool entries to each other. Once a service board fails, the other service board processes all services.