+ *
+ * There are apparently versions of the request with both
+ * 2 bytes and 3 bytes of value. The 3 bytes of value
+ * appear to be a 1-byte application type followed by a
+ * 2-byte VLAN ID; the 2 bytes of value are unknown
+ * (they're 0x20 0x00 in some captures I've seen; that
+ * is not a valid VLAN ID, as VLAN IDs are 12 bits).
+ *
+ * The replies all appear to be 3 bytes long.