S A B D C T = 0 S gets message from above and sends messages to A, C and D S
S A B D C T = 1 C gets a message from S and sends to A, B and D S C
S A B D C T = 2 The messages are on their way S C
S A B D C T = 3 S C D A A receives a message from S and sends to B and C D receives a message from C and sends to S and B
S A B D C T = 4 B receives a message from C and sends to A and D S C D A B
S A B D C T = 5 B receives a message from D S C D A B
S A B D C T = 6 A receives a message from C B receives a message from A and sends a message to C D receives messages from S and B and sends a message to C S C D A B
S A B D C T = 7 A receives a message from B and sends to S S C D A B
S A B D C T = 8 C receives messages from A and from D S C D A B
S A B D C T = 9 S receives a message from D C receives a message from B and sends to S S C D A B
S A B D C T = 10 S receives messages from A and from C S C D A B