delay.tex

\documentclass[tikz]{standalone}
\usepackage{rxmarbles}
\usetikzlibrary[arrows,shapes,positioning,matrix]

\begin{document}
\begin{tikzpicture}

\matrix[row sep=0.5cm]
{
  \draw [time] (0,0) -- (3.8,0);
  \coordinate (0x0) at (0.3,0);
  \node[marble,circle,yellow] (1x0) at (1,0) {};
  \node[marble,circle,green] (2x0) at (2,0) {};
  \node[marble,circle,cyan] (3x0) at (3,0) {};
  \node[complete] (4x0) at (3.5,0) {};
  \\
  
  \node[box,minimum width=7cm] (op) {Delay ($\Delta t$)};
  \\
  
  \draw [time] (0,0) -- (5.55,0);
  \node[marble,circle,yellow] (1x2) at (2.75,0) {};
  \node[marble,circle,green] (2x2) at (3.75,0) {};
  \node[marble,circle,cyan] (3x2) at (4.75,0) {};
  \node[complete] (4x2) at (5.25,0) {};
  \\
};

\draw [subscribe] (0x0) -- (0x0|-op.north) node[above,sloped,pos=0.5] {\tiny{subscribe}};
\draw [fdash] (1x0) -- (1x0|-op.north);
\draw [fdash] (2x0) -- (2x0|-op.north);
\draw [fdash] (3x0) -- (3x0|-op.north);
\draw [fdash] (4x0) -- (4x0|-op.north);

\draw [rdash] (1x2) -- (1x2|-op.south);
\draw [rdash] (2x2) -- (2x2|-op.south);
\draw [rdash] (3x2) -- (3x2|-op.south);
\draw [rdash] (4x2) -- (4x2|-op.south);

\end{tikzpicture}
\end{document}