- OFPT_FEATURES_REQUEST, /* 0 Controller/switch message */
- OFPT_FEATURES_REPLY, /* 1 Controller/switch message */
- OFPT_GET_CONFIG_REQUEST, /* 2 Controller/switch message */
- OFPT_GET_CONFIG_REPLY, /* 3 Controller/switch message */
- OFPT_SET_CONFIG, /* 4 Controller/switch message */
- OFPT_PACKET_IN, /* 5 Async message */
- OFPT_PACKET_OUT, /* 6 Controller/switch message */
- OFPT_FLOW_MOD, /* 7 Controller/switch message */
- OFPT_FLOW_EXPIRED, /* 8 Async message */
- OFPT_TABLE, /* 9 Controller/switch message */
- OFPT_PORT_MOD, /* 10 Controller/switch message */
- OFPT_PORT_STATUS, /* 11 Async message */
- OFPT_ERROR_MSG, /* 12 Async message */
- OFPT_STATS_REQUEST, /* 13 Controller/switch message */
- OFPT_STATS_REPLY /* 14 Controller/switch message */
+ /* Immutable messages. */
+ OFPT_HELLO, /* Symmetric message */
+ OFPT_ERROR, /* Symmetric message */
+ OFPT_ECHO_REQUEST, /* Symmetric message */
+ OFPT_ECHO_REPLY, /* Symmetric message */
+ OFPT_VENDOR, /* Symmetric message */
+
+ /* Switch configuration messages. */
+ OFPT_FEATURES_REQUEST, /* Controller/switch message */
+ OFPT_FEATURES_REPLY, /* Controller/switch message */
+ OFPT_GET_CONFIG_REQUEST, /* Controller/switch message */
+ OFPT_GET_CONFIG_REPLY, /* Controller/switch message */
+ OFPT_SET_CONFIG, /* Controller/switch message */
+
+ /* Asynchronous messages. */
+ OFPT_PACKET_IN, /* Async message */
+ OFPT_FLOW_EXPIRED, /* Async message */
+ OFPT_PORT_STATUS, /* Async message */
+
+ /* Controller command messages. */
+ OFPT_PACKET_OUT, /* Controller/switch message */
+ OFPT_FLOW_MOD, /* Controller/switch message */
+ OFPT_PORT_MOD, /* Controller/switch message */
+ OFPT_TABLE, /* Controller/switch message */
+
+ /* Statistics messages. */
+ OFPT_STATS_REQUEST, /* Controller/switch message */
+ OFPT_STATS_REPLY /* Controller/switch message */