diff --git a/ceilometer_zvm/compute/virt/zvm/inspector.py b/ceilometer_zvm/compute/virt/zvm/inspector.py
index 1a862d0..588ea77 100644
--- a/ceilometer_zvm/compute/virt/zvm/inspector.py
+++ b/ceilometer_zvm/compute/virt/zvm/inspector.py
@@ -68,13 +68,15 @@ class ZVMInspector(virt_inspector.Inspector):
                 parameters=None,
                 rx_bytes=nic['nic_rx'],
                 rx_packets=nic['nic_fr_rx'],
-                # rx_bytes_delta was taken out from zcc
+                # rx_bytes_delta was taken out from zcc in ussuri version,
+                # and put it back because antelope version is needed.
                 rx_bytes_delta=None,
                 rx_errors=nic['nic_fr_rx_err'],
                 rx_drop=None,
                 tx_bytes=nic['nic_tx'],
                 tx_packets=nic['nic_fr_tx'],
-                # tx_bytes_delta was taken out from zcc
+                # tx_bytes_delta was taken out from zcc in ussuri version,
+                # and put it back because antelope version is needed.
                 tx_bytes_delta=None,
                 tx_errors=nic['nic_fr_tx_err'],
                 tx_drop=None