Systems and methodologies are described that facilitate assigning indices to link assignment blocks (LABs) communicated via a downlink. Indices in a first subset are allocated to shared LABs, which are decoded by a plurality of access terminals. Indices in a second subset are assigned to unshared LABs, which are each intended for a particular recipient access terminal. Assignment of an index for each unshared LAB can be based upon a hash of an identifier corresponding to an intended recipient access terminal and/or access terminal capabilities. Moreover, an access terminal can decode LABs based upon corresponding indices. LABs with indices in a first range can be identified as shared LABs and decoded. Further, the access terminal can determine a second range of indices corresponding to unshared LABs to decode; the second range of indices includes fewer than all indices corresponding to unshared LABs in a frame sent by a base station.