A Q-learning based cross layer approach is proposed in . Instead of hop count or depth, Q-learning routing path selection process includes traffic load, latency and queue length. Q-learning in distributed nodes ensures balanced energy consumption. Path Unaware Layered Routing Protocol (PULRP) with uniform deployment of nodes and with non uniform deployment of nodes is proposed in . It consists of two phases, the first phase called the layering phase, in which spherical layers of radius Rr with sink as layer 0 are formed and layering number is increased by each node. A node in layer l is to find forwarder from layer l−1 on the basis of transmission range and layering radius. The second phase is called communication phase in which potential relay nodes from each layer are selected for packet forwarding. Energy optimized-PULRP  is an enhancement in which so called on the fly routing is considered to select relay node. E-PULRP incorporate energy in routing decisions, which was not considered in previous versions.