METHODS, APPARATUSES, SYSTEM AND COMPUTER PROGRAMS FOR KEY UPDATE

摘要

It is disclosed a method comprising monitoring validity of limited-validity key information, acquiring, from a network entity upon invalidity of the limited-validity key information, limited-validity transaction identification information based on unlimited-validity identification information identifying a terminal, generating new limited-validity key information based on the acquired limited-validity transaction identification information, and transmitting the acquired limited-validity transaction identification information to a network element.