The useful engineering distinction is that Counter Check carries network-provided COUNT MSBs, while Counter Check Response carries the UE-reported COUNT values used for comparison.
The transaction identifier should line up with the earlier Counter Check request.
The DRB identities should match the bearer set under investigation.
The returned values are most useful when interpreted next to the earlier network-provided COUNT MSB information.
Important Information Elements
IE
Required
Description
rrc-TransactionIdentifier
Yes
Correlates the UE response with the earlier Counter Check request.
drb-CountInfoList
Yes
List of DRBs and the UE-reported COUNT values.
drb-Identity
Yes
Identifies which DRB each returned COUNT entry belongs to.
count-Uplink
Yes
UE view of uplink COUNT derived from TX_NEXT - 1 for the DRB.
count-Downlink
Yes
UE view of downlink COUNT derived from RX_NEXT - 1 for the DRB.
Detailed field explanation
rrc-TransactionIdentifier
Correlates the UE response with the earlier Counter Check request.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
drb-CountInfoList
List of DRBs and the UE-reported COUNT values.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
drb-Identity
Identifies which DRB each returned COUNT entry belongs to.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
count-Uplink
UE view of uplink COUNT derived from TX_NEXT - 1 for the DRB.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
count-Downlink
UE view of downlink COUNT derived from RX_NEXT - 1 for the DRB.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
What to check in logs and traces
Confirm Counter Check Response follows a real Counter Check for the same transaction context.
Match rrc-TransactionIdentifier with the earlier request.
Verify the listed DRBs exist in the UE and network bearer context.
Compare returned COUNT values with the network-provided COUNT MSB information from Counter Check.
If user-plane symptoms persist, correlate with PDCP, RLC, and mobility traces rather than relying only on this response.
Check whether the response is timely and complete for all expected DRBs.
Common Issues and Troubleshooting
Counter Check Response is missing.
Likely cause: The UE may not have completed the comparison, the signaling path may have broken, or the trace may miss the response.
What to inspect: Check SRB1 continuity, radio stability, and whether the request and response window is fully captured.
Next step: Correlate with mobility interruption, bearer release, or connection failure.
Returned DRB list does not match the expected bearer set.
Likely cause: The active bearer map may differ from the engineer's assumption, or the trace context may be stale.
What to inspect: Check recent RRC Reconfiguration and bearer setup history.
Next step: Validate the DRB map before concluding the response is malformed.
Counter Check Response looks normal but user-plane continuity is still bad.
Likely cause: The root problem may be outside PDCP COUNT alignment.
What to inspect: Correlate with PDCP, RLC, forwarding, transport, and mobility execution traces.
Next step: Use Counter Check Response as one verification point, not the whole diagnosis.
LTE / 5G / Variant Comparison
Counter Check Response versus Counter Check
Counter Check is the request from the network. Counter Check Response is the UE reply with the compared COUNT values.
Decode this message with the 3GPP Decoder, inspect the related message database, or open the matching call flow to see where this signaling step fits in the full procedure.