Let $n\geq 5$ and $m\geq 1$ be positive integers. Let $S = ( s_1, s_2, \ldots , s_m)$ be a sequence of integers such that $1 \leq s_1 < s_2 < \ldots < s_m \leq \lfloor \frac{n-1}{2} \rfloor.$ In this paper, we discuss the diameter of multi-loop networks $C_n(s_1,s_2, \ldots, s_m)$ when $s_1=1$. We also present a relation between the diameter of multi-loop networks and the diameter of generalized Petersen graphs.