When operators deploy the Transmission Control Protocol
(TCP) retransmission identification function to differentially charge
retransmission packets of users, you need to commission the function
of the UGW9811 and ensure that this function can be used.

Here, the
R7 enhanced GGSN charging data record (eG-CDR) in offline charging
mode is taken as an example to show how to commission the content-based
charging (CBC) function for TCP retransmission packets. Configure
the CBC function of the user profile for TCP retransmission packets.
The retransmitted packets are charged according to a special tariff.
Observe whether the TCP service traffic can be correctly recorded
to the rating group (RG) of the rule.

In this example, routes
are deleted or black hole routes are configured so that instant packet
loss occurs. Then, the routes are recovered. In this manner, the scenario
where packets are retransmitted is reproduced.