Assessing the impact of Link Layer Feedback mechanisms on MANET routing protocols

Mobile ad hoc networks have a highly dynamic topology due to terminal mobility. Ad hoc routing protocols can cope with this mobility as they search for an alternative route when a currently-in-use path breaks. Despite of their ability to recover from path failures, the time elapsed until the route is reestablished deteriorates network performance. MANET routing protocols can detect link breakages faster when Link Layer Feedback (LLF) mechanisms are used. In this paper we evaluate the advantages and drawbacks of using feedback mechanisms. Our simulation results show that these mechanisms are appropriate for low mobility conditions. In contrast, feedback is not adequate for scenarios where terminals move faster due to frequent collisions mistaken as link breakages.