Every radio link is considered working in three separate ZONEs: GOOD ZONE: When it is working between the HITLESS profile (included) and the UPPER profile (included) HITLESS ZONE: When it is working between the LOWER profile (included) and the HITLESS profile (excluded) BAD ZONE: When the modem is unlocked HITLESS profile (one for each radio link) is last profile that is considered good for L1 aggregation. NE is in charge to select which of the links that are working into the HITLESS ZONE participate in L1 aggregation. The decision is taken according to three possible behaviors: hlAggrL1AllSurvive(1): All links remain used by aggregator when working into the HITLESS ZONE. hlAggrL1OneSurvive(2): When NO link is working into the GOOD ZONE, the last link entered into the HITLESS ZONE continues to be used by the aggregator hlAggrL1NoneSurvive(3): Each link is removed from aggregation when working into the HITLESS ZONE