LTE: How counter check procedure work and what is the significance and benifit of it ?

Question

I am looking for actual use of this procedure ?

Answer 1

Counter check procedure used by eNodeB to verify the current uplink and downlink count for a bearer.
The purpose of using this procedure is "check whether an intruder has inserted the packet or not.

In this procedure, eNodeB sends "Counter Check" message for a set of DRBs to an UE.
In turn, UE sends "Counter check response" to eNodeB. Based of the response eNodeB may take some action like re-activation of AS security or release of a particular bearer or even release of ue connection itself.

Comments

Counter Check procedure is always initiated by eNB by sending "Counter check " messahe to UE
Purpose:->To instruct UE for checking no. of data transmitted/received from each/in DRB.
When:->Whenever eNB finds the particular count is exceeded than a specific value
Why:->eNB sends this message if it is suspect that new data is introduced by an intruder in any DRB which is used for data transfer b/w UE and eNB.
Action:->UE will send Counter check response to eNB, by including drb-countInfoList,drb-Identity,countUL,CountDL IEs corresponding to that specific count value.