\begin{tikzpicture}
	\begin{pgfonlayer}{nodelayer}
		\node [style=generic block] (0) at (0, 0) {Initiator};
		\node [style=generic block] (1) at (10, 0) {Inter-\\connect};
		\node [style=generic block] (2) at (20, 0) {Target};
		\node [style=payload] (3) at (10, 4) {Generic\\Payload};
		\node [style=initiator socket] (4) at (2, 0) {};
		\node [style=target socket] (5) at (8, 0) {};
		\node [style=target socket] (6) at (18, 0) {};
		\node [style=initiator socket] (7) at (12, 0) {};
		\node [style=none] (8) at (5, 0.5) {Forward Path};
		\node [style=none] (9) at (15, 0.5) {Forward Path};
		\node [style=none] (10) at (8, -2) {};
		\node [style=none] (11) at (2, -2) {};
		\node [style=none] (12) at (18, -2) {};
		\node [style=none] (13) at (12, -2) {};
		\node [style=none] (14) at (5, -1.5) {Backward Path};
		\node [style=none] (15) at (15, -1.5) {Backward Path};
	\end{pgfonlayer}
	\begin{pgfonlayer}{edgelayer}
		\draw [style=dashed arrow, bend left=15] (0) to (3);
		\draw [style=arrow] (4) to (5);
		\draw [style=arrow] (7) to (6);
		\draw (5) to (10.center);
		\draw (11.center) to (10.center);
		\draw (6) to (12.center);
		\draw (12.center) to (13.center);
		\draw [style=arrow] (13.center) to (7);
		\draw [style=arrow] (11.center) to (4);
		\draw [style=dashed arrow, bend left=15] (3) to (2);
	\end{pgfonlayer}
\end{tikzpicture}