Control Layer - Part 1 (HSS)

After writing about the IMS technology architecture, we will analyze more deeply the control layer . As seen, in this layer is responsible to make the connection between devices and services, abstracting the used network.

Today, we write about the HSS (Home Subscriber Server)
HSS is like a devices' central database of IMS network, it's responsible for the authentication information, authorization and physical location. It stores the users profiles and their services, independently of the service provider.

HSS is an evolution of the HLR (Home Location Register), which is a node specified by the GSM architecture.

According to the 3GPP specification, HSS provides the establishment of calls and / or meetings, creation of security information devices and identification and authorization to access them. It interacts with CSCF (Call Session Control Function) through Diameter protocol.