MK       = PRF'(IK'|CK',"EAP-AKA'"|Identity) 
MK_ECDHE = PRF'(IK'|CK'|SHARED_SECRET,"EAP-AKA' FS"|Identity)
K_encr   = MK[0..127]
K_aut    = MK[128..383]
K_re     = MK_ECDHE[0..255]
MSK      = MK_ECDHE[256..767]
EMSK     = MK_ECDHE[768..1279]