\documentclass[12pt,oneside]{bidipresentation}
\usepackage[RL]{flowfram}
\geometry{paperwidth=225mm,paperheight=180mm,rmargin=40mm,lmargin=4mm,top=10mm,bottom=10mm}
\usepackage{hyperref}

\newstaticframe{30mm}{\paperheight}%
{\dimexpr(\paperwidth-40mm)}% Why minus 40mm? because your rmargin=40mm in your geometry setup
{0.5\paperheight}[sidebar]
\setstaticframe*{sidebar}{valign=b}
\usepackage{xepersian}

\begin{document}

\section{لایه فیزیکی} \label{sec:section2}
\url{‎http://www.dialogic.com/en/products/signaling-and-ss7-components/download/dsi-network-interface-boards.aspx}‎

\end{document}