diff --git a/tests/tcp/tcp-phi1.pml b/tests/tcp/tcp-phi1.pml
index a8da96a..e058160 100644
--- a/tests/tcp/tcp-phi1.pml
+++ b/tests/tcp/tcp-phi1.pml
@@ -4,9 +4,9 @@
 mtype = { SYN, FIN, ACK, ABORT, CLOSE, RST, OPEN }
 
 chan AtoN = [1] of { mtype };
-chan NtoA = [0] of { mtype };
+chan NtoA = [1] of { mtype };
 chan BtoN = [1] of { mtype };
-chan NtoB = [0] of { mtype };
+chan NtoB = [1] of { mtype };
 
 int state[2];
 int pids[2];
diff --git a/tests/tcp/tcp-phi2.pml b/tests/tcp/tcp-phi2.pml
index d423edc..f3aa304 100644
--- a/tests/tcp/tcp-phi2.pml
+++ b/tests/tcp/tcp-phi2.pml
@@ -4,9 +4,9 @@
 mtype = { SYN, FIN, ACK, ABORT, CLOSE, RST, OPEN }
 
 chan AtoN = [1] of { mtype };
-chan NtoA = [0] of { mtype };
+chan NtoA = [1] of { mtype };
 chan BtoN = [1] of { mtype };
-chan NtoB = [0] of { mtype };
+chan NtoB = [1] of { mtype };
 
 int state[2];
 int pids[2];
diff --git a/tests/tcp/tcp-phi3.pml b/tests/tcp/tcp-phi3.pml
index b1e9e80..811c8f3 100644
--- a/tests/tcp/tcp-phi3.pml
+++ b/tests/tcp/tcp-phi3.pml
@@ -4,9 +4,9 @@
 mtype = { SYN, FIN, ACK, ABORT, CLOSE, RST, OPEN }
 
 chan AtoN = [1] of { mtype };
-chan NtoA = [0] of { mtype };
+chan NtoA = [1] of { mtype };
 chan BtoN = [1] of { mtype };
-chan NtoB = [0] of { mtype };
+chan NtoB = [1] of { mtype };
 
 int state[2];
 int pids[2];
diff --git a/tests/tcp/tcp-phi4.pml b/tests/tcp/tcp-phi4.pml
index 3ca2932..8438d9f 100644
--- a/tests/tcp/tcp-phi4.pml
+++ b/tests/tcp/tcp-phi4.pml
@@ -4,9 +4,9 @@
 mtype = { SYN, FIN, ACK, ABORT, CLOSE, RST, OPEN }
 
 chan AtoN = [1] of { mtype };
-chan NtoA = [0] of { mtype };
+chan NtoA = [1] of { mtype };
 chan BtoN = [1] of { mtype };
-chan NtoB = [0] of { mtype };
+chan NtoB = [1] of { mtype };
 
 int state[2];
 int pids[2];
diff --git a/tests/tcp/tcp-phi5.pml b/tests/tcp/tcp-phi5.pml
index e675b63..a1bbc27 100644
--- a/tests/tcp/tcp-phi5.pml
+++ b/tests/tcp/tcp-phi5.pml
@@ -4,9 +4,9 @@
 mtype = { SYN, FIN, ACK, ABORT, CLOSE, RST, OPEN }
 
 chan AtoN = [1] of { mtype };
-chan NtoA = [0] of { mtype };
+chan NtoA = [1] of { mtype };
 chan BtoN = [1] of { mtype };
-chan NtoB = [0] of { mtype };
+chan NtoB = [1] of { mtype };
 
 int state[2];
 int pids[2];
diff --git a/tests/tcp/tcp-phi6.pml b/tests/tcp/tcp-phi6.pml
index fc14aeb..4624caa 100644
--- a/tests/tcp/tcp-phi6.pml
+++ b/tests/tcp/tcp-phi6.pml
@@ -4,9 +4,9 @@
 mtype = { SYN, FIN, ACK, ABORT, CLOSE, RST, OPEN }
 
 chan AtoN = [1] of { mtype };
-chan NtoA = [0] of { mtype };
+chan NtoA = [1] of { mtype };
 chan BtoN = [1] of { mtype };
-chan NtoB = [0] of { mtype };
+chan NtoB = [1] of { mtype };
 
 int state[2];
 int pids[2];
diff --git a/tests/tcp/tcp.pml b/tests/tcp/tcp.pml
index be7125b..1780927 100644
--- a/tests/tcp/tcp.pml
+++ b/tests/tcp/tcp.pml
@@ -4,9 +4,9 @@
 mtype = { SYN, FIN, ACK, ABORT, CLOSE, RST, OPEN }
 
 chan AtoN = [1] of { mtype };
-chan NtoA = [0] of { mtype };
+chan NtoA = [1] of { mtype };
 chan BtoN = [1] of { mtype };
-chan NtoB = [0] of { mtype };
+chan NtoB = [1] of { mtype };
 
 int state[2];
 int pids[2];