A method for a communication network comprising: receiving, by a first Home eNodeB,HeNB a first attach request from a user equipment,UE, for attaching a subscriber associated with the UE to a small cell network; determining, by the first HeNB, whether the subscriber has transitioned into the small cell network from a macro cell network; exchanging, based on the determination, a first pair of messages between the first HeNB and the UE to determine an International Mobile Subscriber Identity,IMSI, of the subscriber; and exchanging, based on the determination, one or more second pairs of messages between the first HeNB and the UE to advance a sequence number for Non-Access Stratum,NAS, messages for the UE to a value corresponding to a received sequence number for the first attach request from the UE, further comprising: receiving, by a second HeNB, a second attach request from the UE for attaching the subscriber to the small cell network; determining, by the second HeNB, whether the subscriber has transitioned to the second HeNB from another HeNB in the small cell network; and retrieving, by a Home eNodeB gateway, HeNB-GW, the IMSI of the subscriber by recovering an association of the IMSI with a Globally Unique Mobility Management Entity Identity, GUMMEI, and a Mobility Management Entity UE S1AP Identity, MME UE S1AP ID, for the subscriber if the subscriber has transitioned to the second HeNB from another HeNB in the small cell network. receiving, by a first Home eNodeB,HeNB a first attach request from a user equipment,UE, for attaching a subscriber associated with the UE to a small cell network; determining, by the first HeNB, whether the subscriber has transitioned into the small cell network from a macro cell network; exchanging, based on the determination, a first pair of messages between the first HeNB and the UE to determine an International Mobile Subscriber Identity,IMSI, of the subscriber; and exchanging, based on the determination, one or more second pairs of messages between the first HeNB and the UE to advance a sequence number for Non-Access Stratum,NAS, messages for the UE to a value corresponding to a received sequence number for the first attach request from the UE, further comprising: receiving, by a second HeNB, a second attach request from the UE for attaching the subscriber to the small cell network; determining, by the second HeNB, whether the subscriber has transitioned to the second HeNB from another HeNB in the small cell network; and retrieving, by a Home eNodeB gateway, HeNB-GW, the IMSI of the subscriber by recovering an association of the IMSI with a Globally Unique Mobility Management Entity Identity, GUMMEI, and a Mobility Management Entity UE S1AP Identity, MME UE S1AP ID, for the subscriber if the subscriber has transitioned to the second HeNB from another HeNB in the small cell network. receiving, by a second HeNB, a second attach request from the UE for attaching the subscriber to the small cell network; determining, by the second HeNB, whether the subscriber has transitioned to the second HeNB from another HeNB in the small cell network; and retrieving, by a Home eNodeB gateway, HeNB-GW, the IMSI of the subscriber by recovering an association of the IMSI with a Globally Unique Mobility Management Entity Identity, GUMMEI, and a Mobility Management Entity UE S1AP Identity, MME UE S1AP ID, for the subscriber if the subscriber has transitioned to the second HeNB from another HeNB in the small cell network.