communication with the access network the reverse access channel is also used by access terminals to obtain timing corrections reverse acknowledgement channel r ackch which carries acknowledgement information of the f dch reception reverse beam feedback channel r bfch which carries information about the beam index and the quality of the forward link channel reverse channel quality indicator channel r cqich which carries information about the quality of the forward link channel of a sector as received by an access terminal the reverse channel quality indicator channel also carries information about the desired forward link serving sector reverse data channel r dch which carries information from an access terminal the reverse data channel is assigned to an access terminal by the f ssch assignment reverse pilot channel r pich which carries the pilot reverse request channel r reqch which carries information about the buffer level at different quality of service classes for an access terminal the reverse request channel also carries information about the desired revere link serving sector reverse subband feedback channel r sfch which carries information about the quality of a subband or segment of the forward link channel it should be noted that the channels described above need not be utilized and may be omitted further other channels may be utilized in.