-neighbor. Link estimation can be done in a variety of ways, and we
-do not impose one here. It is decoupled from the establishment of
-routes. There is a narrow interface -- LinkEstimator -- between the
-link estimator and the routing engine. The one requirement is that
-the quality returned is standardized. A smaller return value from
-LinkEstimator.getQuality(), LinkEstimator.getforwardQuality(),
-LinkEstimator.getReverseQuality() MUST imply that the link to the
+neighbor. In this TEP, we briefly describe the reference
+implementation in ''tinyos-2.x/tos/lib/4bitle'' and refer the readers
+to [3]_ for detailed description of the estimator.
+
+Link estimation is decoupled from the establishment of routes. There
+is a narrow interface -- LinkEstimator and CompareBit -- between the
+link estimator and the routing engine. The one requirement is that the
+quality returned is standardized. A smaller return value from
+LinkEstimator.getLinkQuality() MUST imply that the link to the