diff --git a/msg.h b/msg.h
index f9ae85a..44c6134 100644
--- a/msg.h
+++ b/msg.h
@@ -27,6 +27,8 @@
 #include "ddt.h"
 #include "transport.h"
 
+#define PTP_VERSION 2
+
 /* Values for the messageType field */
 #define SYNC                  0x0
 #define DELAY_REQ             0x1
diff --git a/port.c b/port.c
index a13da2a..c389b23 100644
--- a/port.c
+++ b/port.c
@@ -38,8 +38,6 @@
 
 #define PORT_MAVE_LENGTH 10
 
-#define PTP_VERSION 2
-
 struct port {
 	char *name;
 	struct clock *clock;