ECF based forwarding function is utilized when depth of node is between D1=150 and D2=350. ECF is defined as: (15c)ECF=pv×ErDi where Di can be between D1 and D2. Value of Er is between 0 and 70 J and this results ECF values between [0, 70] which is very different from the range in SQI based forwarding function. ECF is also modified to include transmission range and depth threshold. If node is in deepest region of networks with depth greater than D2, DDF based forwarding function is employed using following equation. (15d)DDF=SQI×liDi