Disclosed is a method of rekeying radios for link layer encryption (LLE) in a radio network using a bifurcated crypto period. During a first portion of a first LLE crypto period during which a first LLE key (LEK) is used to LLE encrypt communications between a base station and mobile stations operating within a corresponding coverage area of the base station, a radio network communications device prevents individual ones of the mobile stations from requesting a second LEK to be used during a second LLE crypto period after the first LLE crypto period. During a second portion of the first LLE crypto period, the radio network communications device allows individual ones of the mobile stations to request the second LEK. A mobile station configured to operate in accordance with the bifurcated crypto period, and provide information regarding keys in its possession via an authentication response ISP, is also disclosed.