diff --git a/src/vnet/ethernet/p2p_ethernet.api b/src/vnet/ethernet/p2p_ethernet.api
index 72a7342..8fb6637 100644
--- a/src/vnet/ethernet/p2p_ethernet.api
+++ b/src/vnet/ethernet/p2p_ethernet.api
@@ -18,6 +18,7 @@
   u32 client_index;
   u32 context;
   u32 parent_if_index;
+  u32 subif_id;
   u8  remote_mac[6];
 };