Subscription data mechanism

Source of the subscription data

HLR

HSS

Protocol stack used for data transmission

MAP+SS7

Diameter+SCTP

Addressing method used in obtaining the subscription data

Global title (GT) addressing method which selects the HLR
of the HPLMN based on the international mobile subscriber identity
(IMSI).

Select the HSS based on the IMSI.

Basis

IMSI

IMSI

Procedure for obtaining the subscription data

The subscription data obtaining procedure and the authentication
procedure are performed separately.

The subscription data obtaining procedure and the authentication
procedure are performed separately.

Saving policy of the subscription data

After a UE is registered with the network, the subscription
data is saved on the SGSN. After the UE is detached, the data can
still be saved on the SGSN.

After a UE is registered with the network, the subscription
data is saved on the MME. After the UE is detached, the data can still
be saved on the MME.

Update policy of the subscription data

When the subscription data is changed, the HLR synchronizes
the data to the SGSN.

When the subscription data is changed, the HSS synchronizes
the data to the MME.