diff --git a/openflow_input/bsn_tlv b/openflow_input/bsn_tlv
index e25e2de..59fa53a 100644
--- a/openflow_input/bsn_tlv
+++ b/openflow_input/bsn_tlv
@@ -402,3 +402,9 @@
     uint16_t table_id;
     list(of_bsn_tlv_t) key;
 };
+
+struct of_bsn_tlv_ipv4_netmask : of_bsn_tlv {
+    uint16_t type == 60;
+    uint16_t length;
+    of_ipv4_t value;
+};