nal State During the Operational State, the relay station performs the tasks that are required to transmit and/or receive user data in the access (i.e., the radio link between the mobile station and the relay station) or relay link (i.e., the path between the relay station and the base station). Figures 4-16 and 4-17 show the state machines for the relay-enabled base station and relay station compliant with the IEEE 802.16j- 2009 standard. It must be noted that the legacy mobile stations are not relay-aware, and IEEE 802.16j- 2009 standard compliant relays assume that the access link protocols between the MS and RS remain identical to those specified by the IEEE 802.16-2009 standard to avoid interoperability issues. However, the IEEE 802.16m-compliant devices are relay-aware, (i.e., different cell identifier code subsets are assigned to various cell types) facilitating the discovery and association with the relay stations, as well as unifying the relay and access link protocols based on the IEEE 802. 16m standard. The RS follows the same scanning and synchronization procedure as that specified for the MS. In addition, the RS may store preamble indices and corresponding signal strength information in order to report the stored values to the serving relay-enabled BSX after registration by sending a relay neighbor measurement report during the neighbor station measurement phase and on request. The relay-enabled BS indicates the request for this information through the ranging response message during initial ranging. *It must be noted that not all base stations are relay-enabled, as relay functionality is optional. 4.5 Operational states of femto base stations The second "access station selection" procedure defined in the IEEE 802.16j-2009 standard for multi-hop relay networks may be enabled if an indication is included in the RS network entry opti- mization in the ranging response message. The alternative access station selection may take place after neighbor station measurement reporting stage and before the config