We present statistical models to accurately evaluate the distribution of the lifetime of a wireless link in a mobile ad hoc network (MANET) in which nodes move randomly within constrained areas. We show that link lifetime can be computed through a two-state Markov model and further apply the computed statistics to the optimization of segmentation schemes of information stream. Summarizing all these results, we further provide comprehensive analysis on throughput, delay, and storage requirements for MANETs with restricted node mobility.