fig-sentry-plt.tex

\documentclass[tikz]{standalone}
\input{preamble} % include all the common macros and font settings

\begin{document}
\begin{tikzpicture}

        \matrix [row sep=20pt, column sep=10pt] {
        %
                \node[draw] (i1w) {instance 1 read-write region} ;
        %
        &       \node[draw] (ro) {read-only region} ;
        %
        &       \node[draw] (i2w) {instance 2 read-write region} ;
        %
        \\
        %
                \node[draw] (i1p) {instance 1 PLT} ;
        %
        &
        %
        &       \node[draw] (i2p) {instance 2 PLT} ; \\
        %
        } ;

        \draw [->] (i1p) -| (ro.230) ;
        \draw [->] (i2p) -| (ro.300) ;

        \draw [dotted,->] ([xshift=-10pt]i1w.south) -- ([xshift=-20pt]i1p.north) ;
        \draw [->] ([xshift=20pt]i1p.north) -- ([xshift=10pt]i1w.south) ;

        \draw [dotted,->] ([xshift=-10pt]i2w.south) -- ([xshift=-20pt]i2p.north) ;
        \draw [->] ([xshift=20pt]i2p.north) -- ([xshift=10pt]i2w.south) ;

    \coordinate (i1s) at ([xshift=-05pt,yshift=-10pt]i1p.south) {} ; \draw [->] (i1s) -- ([xshift=-05pt]i1p.south) ;
    \coordinate (i1s) at ([xshift=-10pt,yshift=-10pt]i1p.south) {} ; \draw [->] (i1s) -- ([xshift=-10pt]i1p.south) ;
    \coordinate (i1s) at ([xshift=-15pt,yshift=-10pt]i1p.south) {} ; \draw [->] (i1s) -- ([xshift=-15pt]i1p.south) ;

    \coordinate (i2s) at ([xshift=-05pt,yshift=-10pt]i2p.south) {} ; \draw [->] (i2s) -- ([xshift=-05pt]i2p.south) ;
    \coordinate (i2s) at ([xshift=-10pt,yshift=-10pt]i2p.south) {} ; \draw [->] (i2s) -- ([xshift=-10pt]i2p.south) ;
    \coordinate (i2s) at ([xshift=-15pt,yshift=-10pt]i2p.south) {} ; \draw [->] (i2s) -- ([xshift=-15pt]i2p.south) ;

\end{tikzpicture}
\end{document}