pear to be accurate enough in case MAC reliability is not used as when packet

drops occurs due to collisions buffer drains and size is decreased. Well known schemes

use a combination of channel utilization and buffer occupancy, as seems to be the most

effective method. Fidelity measurement at the sink is also used but is more slow method,

as end-to-and and processing delay is added at the sink.

Talking for Feedback methods local ones are most frequently used as transient

congestion problems are most usual in wireless sensor networks and quick reaction is

needed in these situations.

Control Methods used in different schemes is the most important part. The u