This notification is generated when the qtechBfdSessState object for one or more contiguous entries in qtechBfdSessTable are about to enter the down(2) or adminDown(1) states from some other state. The included values of qtechBfdSessDiag MUST both be set equal to this new state (i.e: down(2) or adminDown(1)). The two instances of qtechBfdSessDiag in this notification indicate the range of indexes that are affected. Note that all the indexes of the two ends of the range can be derived from the instance identifiers of these two objects. For cases where a contiguous range of sessions have transitioned into the down(2) or adminDown(1) states at roughly the same time, the device SHOULD issue a single notification for each range of contiguous indexes in an effort to minimize the emission of a large number of notifications. If a notification has to be issued for just a single qtechBfdSessEntry, then the instance identifier (and values) of the two qtechBfdSessDiag objects MUST be the identical.