% TeX root = ../main.tex
\centering
\begin{tikzpicture}[
        shorten >=1pt,
        >={Stealth[round]},
        node distance=2cm,
        semithick,
        on grid,
        auto,
        initial text=,
        initial above,
    ]
    \draw[helplines] (-3,1) grid (3,-7);
    \node[state,initial]    (l0)                            {$l_0$};
    \node[state]            (li1)   [below left = of l0]    {$l_{i_1}$};
    \node[state]            (lin)   [below right = of l0]   {$l_{i_n}$};
    \node[state]            (li1')  [below = of li1]        {$l_{i_1}'$};
    \node[state]            (lin')  [below = of lin]        {$l_{i_n}'$};
    \node[state]            (lo1)   [below = of li1']       {$l_{o_1}$};
    \node[state]            (lom)   [below = of lin']       {$l_{o_m}$};
    \node[state]            (lo1')  [below = of lo1]        {$l_{o_1}'$};
    \node[state]            (lom')  [below = of lom]        {$l_{o_m}'$};
    \node (center)[below=4.2cm of l0] {};
    \draw[color=gray] (center) ellipse [x radius=3cm,y radius=3cm];
    \path[->]   (li1)     edge    node      {$t_{i_1}$}  (li1')
                (lin)     edge    node      {$t_{i_n}$}  (lin')
                (lo1)     edge    node      {$t_{o_1}$}  (lo1')
                (lom)     edge    node      {$t_{o_m}$}  (lom');
    %todo: squigilly line 
    \draw[->,decorate,decoration={snake,pre length=5pt,post length=10pt}] (l0) -- (li1);
    \draw[->,decorate,decoration={snake,pre length=5pt,post length=10pt}] (l0) -- (lin);
\end{tikzpicture}