diff --git a/test_data/of10/port_mod.data b/test_data/of10/port_mod.data
new file mode 100644
index 0000000..972a4e8
--- /dev/null
+++ b/test_data/of10/port_mod.data
@@ -0,0 +1,18 @@
+-- binary
+01 0f # version/type
+00 20 # length
+00 00 00 02 # xid
+ff fd # port_no
+01 02 03 04 05 06 # hw_addr
+90 ab cd ef # config
+ff 11 ff 11 # mask
+ca fe 67 89 # advertise
+00 00 00 00 # pad
+-- python
+ofp.message.port_mod(
+    xid=2,
+    port_no=ofp.OFPP_CONTROLLER,
+    hw_addr=[1,2,3,4,5,6],
+    config=0x90ABCDEF,
+    mask=0xFF11FF11,
+    advertise=0xCAFE6789)