In earlier issues, we have introduced the IP address-based session binding mechanism of the UPCC. In this issue, we will introduce the derived mechanism of the IP address-based session binding mechanism, that is, Gx session backup mechanism.
Gx session backup mechanism is a redundancy mechanism on the UPCC. In the redundancy mechanism, multiple sets of devices that provide the same functions are deployed in different locations. When a set of devices in one location stops working due to exceptions, such as a fire or earthquake, the other sets of devices can take over services from the faulty devices. As a part of the product reliability design, the redundancy mechanism reduces the impact of external factors (especially disasters) on normal operation of the system.
The process of IP address-based Gx session backup consists of two stages: session backup stage and session restoration stage. In session backup stage, the UPCC backs up and restores session in the database when there is no redundancy scenario. The following video shows the session backup in the example of direct connection networking. In session restoration stage, the UPCC finds and restores the session stored in the database in a redundancy scenario. The Gx link failure is used as an example. For details, see the following video and attachment.