If G(N;r,s) is k-tight optimal DLN and G(N;1,s) is k1-tight optimal DLN,k1>k,then G(N;r,s) is called non-unit step DLN.

• 若G(N;r；s)存在k紧优双环网络；G(N;1；s)存在k1紧优双环网络；且满足k1>k；称G(N;r；s)为非单位步长双环网络.