These cross layer design based protocols use channel sensing and contention methods such as p-persistent CSMA scheme. This is not feasible for mission critical tactical networks where time for decision and response is a key constraint. Secondly in mission critical network collision is intolerable. CL-TDMA reduces call setup time by providing dynamic scheduling and collision free transmission.
TDMA-Based MAC Protocols for Vehicular Ad Hoc Networks
Protocols in this category are specifically designed for congested vehicular networks and are not feasible for using in mission critical tactical networks. These designs do not use the concept of cross-layering causing huge overhead, which is intolerable in tactical networks such as artillery fire control systems. Moreover many protocols in this category use combination of contention based schemes and TDMA, which impacts response time adversely.
Cross Layer based TDMA protocols for Multi-hop Ad-hoc Networks
The protocols in this category are strictly application specific. DD-TDMA specifically targets real-time multiplayer game support [19] and DTSS is developed specifically to support slot scheduling for BeMAP [20], while CL-TDMA can be applied to any TDMA for self-forming and self-healing tactical networks. Moreover in CL-TDMA dynamic slot scheduling is achieved using AODV control messages. This feature provides efficient routing and no separate signaling protocol is required. However DTSS provides low access delay for less denser tactical networks, which is similar to the performance of CL-TDMA but this protocol does not help in routing in the signaling phase.
