diff --git a/src/add-ons/kernel/network/protocols/tcp/TCPEndpoint.cpp b/src/add-ons/kernel/network/protocols/tcp/TCPEndpoint.cpp
index 4fab61628e..74caa4e761 100644
--- a/src/add-ons/kernel/network/protocols/tcp/TCPEndpoint.cpp
+++ b/src/add-ons/kernel/network/protocols/tcp/TCPEndpoint.cpp
@@ -1061,7 +1061,7 @@ TCPEndpoint::SendAcknowledge(bool force)
 void
 TCPEndpoint::_StartPersistTimer()
 {
-	gStackModule->set_timer(&fPersistTimer, 1000000LL);
+	gStackModule->set_timer(&fPersistTimer, TCP_PERSIST_TIMEOUT);
 }
 
 
diff --git a/src/add-ons/kernel/network/protocols/tcp/tcp.h b/src/add-ons/kernel/network/protocols/tcp/tcp.h
index 07d4423022..47fe3f0560 100644
--- a/src/add-ons/kernel/network/protocols/tcp/tcp.h
+++ b/src/add-ons/kernel/network/protocols/tcp/tcp.h
@@ -185,6 +185,7 @@ operator==(tcp_sequence a, tcp_sequence b)
 #define TCP_DEFAULT_MAX_SEGMENT_SIZE	536
 #define TCP_MAX_WINDOW					65535
 #define TCP_MAX_SEGMENT_LIFETIME		60000000	// 60 secs
+#define TCP_PERSIST_TIMEOUT				1000000		// 1 sec
 
 // Minimum retransmit timeout (consider delayed ack)
 #define TCP_MIN_RETRANSMIT_TIMEOUT		200000		// 200 msecs