Technology for communicating security key information from a macro eNB is disclosed. Security key information associated with the macro evolved node B (eNB) may be determined. The security key information may be used to cipher information communicated at the first eNB. A small eNB may be identified at the macro eNB to generate the security key information associated with the macro eNB for ciphering information communicated at the second eNB. The security key information may be communicated, from the macro eNB, to the small eNB for inter-Evolved Universal Terrestrial Radio Access (EUTRA) evolved node B (eNB) carrier aggregation.