\node (emb) [right=of sta] {embedded};
\node (het) [below=of emb,xshift=-3.75em] {heterogeneous};
\node (hom) [right=of het] {homogeneous};
- \draw [->] (dsl) -- (sta);
- \draw [->] (dsl) -- (emb);
- \draw [->] (emb) -- (het);
- \draw [->] (emb) -- (hom);
+ \draw [->,shorten >=2pt] (dsl) -- (sta);
+ \draw [->,shorten >=2pt] (dsl) -- (emb);
+ \draw [->,shorten >=2pt] (emb) -- (het);
+ \draw [->,shorten >=2pt] (emb) -- (hom);
\end{tikzpicture}
\end{document}