diff --git a/src/internet/model/tcp-prr-recovery.h b/src/internet/model/tcp-prr-recovery.h
index d0b94227d..5ee3da533 100644
--- a/src/internet/model/tcp-prr-recovery.h
+++ b/src/internet/model/tcp-prr-recovery.h
@@ -20,7 +20,8 @@
  *         Mohit P. Tahiliani <tahiliani@nitk.edu.in>
  *
  */
-#pragma once
+#ifndef TCP_PRR_RECOVERY_H
+#define TCP_PRR_RECOVERY_H
 
 #include "ns3/tcp-recovery-ops.h"
 
@@ -90,3 +91,4 @@ private:
 };
 } // namespace ns3
 
+#endif /* TCP_PRR_RECOVERY_H */
diff --git a/src/internet/model/tcp-rate-ops.h b/src/internet/model/tcp-rate-ops.h
index 42198b286..c9a4e72cf 100644
--- a/src/internet/model/tcp-rate-ops.h
+++ b/src/internet/model/tcp-rate-ops.h
@@ -16,7 +16,8 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  *
  */
-#pragma once
+#ifndef TCP_RATE_OPS_H
+#define TCP_RATE_OPS_H
 
 #include "ns3/object.h"
 #include "ns3/tcp-tx-item.h"
@@ -263,3 +264,5 @@ bool operator== (TcpRateLinux::TcpRateSample const & lhs, TcpRateLinux::TcpRateS
 bool operator== (TcpRateLinux::TcpRateConnection const & lhs, TcpRateLinux::TcpRateConnection const & rhs);
 
 } //namespace ns3
+
+#endif /* TCP_RATE_OPS_H */
diff --git a/src/internet/model/tcp-recovery-ops.h b/src/internet/model/tcp-recovery-ops.h
index e952087c6..df4b11448 100644
--- a/src/internet/model/tcp-recovery-ops.h
+++ b/src/internet/model/tcp-recovery-ops.h
@@ -20,7 +20,8 @@
  *         Mohit P. Tahiliani <tahiliani@nitk.edu.in>
  *
  */
-#pragma once
+#ifndef TCP_RECOVERY_OPS_H
+#define TCP_RECOVERY_OPS_H
 
 #include "ns3/object.h"
 
@@ -193,3 +194,5 @@ public:
 };
 
 } // namespace ns3
+
+#endif /* TCP_RECOVERY_OPS_H */
diff --git a/src/internet/model/tcp-socket-state.h b/src/internet/model/tcp-socket-state.h
index 686f865aa..842673b30 100644
--- a/src/internet/model/tcp-socket-state.h
+++ b/src/internet/model/tcp-socket-state.h
@@ -15,7 +15,8 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
-#pragma once
+#ifndef TCP_SOCKET_STATE_H
+#define TCP_SOCKET_STATE_H
 
 #include "ns3/object.h"
 #include "ns3/data-rate.h"
@@ -243,3 +244,5 @@ namespace TracedValueCallback {
 }  // namespace TracedValueCallback
 
 } //namespace ns3
+
+#endif /* TCP_SOCKET_STATE_H */
diff --git a/src/internet/model/tcp-tx-item.h b/src/internet/model/tcp-tx-item.h
index 01615d52e..282c46ab2 100644
--- a/src/internet/model/tcp-tx-item.h
+++ b/src/internet/model/tcp-tx-item.h
@@ -16,7 +16,8 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  *
  */
-#pragma once
+#ifndef TCP_TX_ITEM_H
+#define TCP_TX_ITEM_H
 
 #include "ns3/packet.h"
 #include "ns3/nstime.h"
@@ -113,3 +114,5 @@ private:
 };
 
 } //namespace ns3
+
+#endif /* TCP_TX_ITEM_H */