# Simple procedure to put this in latex

I am trying to include the following in one of my articles. I tried to do this with msc and tikz but did not get good result. I am looking for some simple solution since the figure is very simple. Also, mind the alignment of the text. Can you please tell me or give some hints?

• Welcome to TeX.SE. I would propose that you show us your minimal working example with tikz (or even with msc), so that we just add some enhancements and comments. It is much easier than to do it from scratch (and perhaps you may learn a bit more this way). – Jürgen Jun 1 '17 at 11:45

I've always been too thick to understand tikz so I give a solution with tabular

\documentclass[a4paper,12pt]{article}

\usepackage{amsmath,array}

\begin{document}

\renewcommand*{\arraystretch}{2}

\begin{tabular}{|l|}
\hline
My procedure (input : c, input : d) \\
\hline
\begin{tabular}{r>{$}c<{$}l}
John does $a$\\
John calculates $b$ \\
& \xrightarrow{\qquad\text{sends $(a,b)$}\qquad} & Peter receives $a$, $b$ \\
& & calculates $c$, $d$ \\
& \xleftarrow{\qquad\text{sends $(c,d)$}\qquad}\\
John receives $c$, $d$
\end{tabular} \\
\hline
\end{tabular}
\end{document}


• thank you. I thought about this too. But the problem will be when I want to put name. It will come as TABLE. X. Whereas I want it to come as protocol. – Rick Jun 1 '17 at 12:36
• @user2764478 No idea what you mean by "I want it to come as protocol". It will come as "Table" if you put it in a table environment, but no one forces you to do that. And you'd have the same problem no matter how you draw the table/picture, if I understand what you mean. – campa Jun 1 '17 at 12:39
• Sorry for the inconvenience. I want the caption of the table to start with something else than TABLE. – Rick Jun 1 '17 at 12:44
• @user2764478 It sounds to me like you want to define a new floating environment. You can give a look to the newfloat package, but there are also others. – campa Jun 1 '17 at 12:53