Drawing network topology diagrams with Tikz

topo.tex

\usepackage{tikz}
\usetikzlibrary{arrows.meta,bending,automata,shapes}

\begin{tikzpicture}[,>={Stealth[round]},shorten >=1pt,auto,semithick]

  \tikzstyle{host}=[rectangle,draw=black,minimum size=30pt,inner sep=0pt]
  \tikzstyle{switch}=[circle,draw=black,minimum size=30pt,inner sep=0pt]
  \tikzstyle{middlebox}=[diamond,draw=black,minimum size=30pt,inner sep=0pt]

  \node[host]      (h1) at (1,0)  {\texttt{h1}};
  \node[host]      (h2) at (5,0)  {\texttt{h2}};
  \node[switch]    (s1) at (3,0)  {\texttt{s1}};
  \node[middlebox] (l1) at (3,-2) {\texttt{l1}};
  \node[middlebox] (l2) at (3,2)  {\texttt{l2}};

  \path (h1) edge (s1)
        (h2) edge (s1)
        (l1) edge (s1)
        (l2) edge (s1) ;
\end{tikzpicture}

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