diff --git a/include/netinet/if_ether.h b/include/netinet/if_ether.h
index 33f08a31..f7df5f7f 100644
--- a/include/netinet/if_ether.h
+++ b/include/netinet/if_ether.h
@@ -5,6 +5,7 @@
 #include <sys/types.h>
 
 #define ETH_ALEN	6
+#define ETH_TLEN	2
 #define ETH_HLEN	14
 #define ETH_ZLEN	60
 #define ETH_DATA_LEN	1500