DBR and other depth based protocols select neighbors on the base of depth difference Δd between the depth of previous (dp) and current node (dc). Holding time in DBR is also function of depth. Depth of broadcasting nodes can have range from; transmission range RT to maximum depth Dmax, which directly affects the holding time calculations. So this fails to explain the upper and lower bounds on possible holding time values while considering the delay and packet suppression tradeoff.