The Home Subscriber Server (HSS) Emulator allows you to validate the network performance and capacity in a realistic network environment with a mix of subscriber profiles, replicating a deployed configuration. As a HSS simulator, it provides mobile subscriber data repository, authentication information, and routing information services for SGSN testing in UMTS networks, SGSN and MME testing in LTE networks, AAA testing in LTE networks, and AS and CSCF testing in the IMS.
Network Interface Support
The HSS Emulator supports both 3G and 4G interfaces and can be used simultaneously to support evolution deployment testing and roaming or fallback scenarios.
- HSS Emulator 4G interfaces: S6a, S6d, S6m/S6n, S6t, S6c, SLh, Sp, SWx, Cx, Sh, and S13 (Simulated EIR functionality)
- HSS Emulator 3G interfaces: Gr, Wx, and Cx (see our HLR Emulator for more 3G interfaces)
When an HSS Emulator supports multiple interfaces, it also supports the interaction between those interfaces.
- Multiple S6a interfaces enable support for MME-MME mobility;
- S6a and S6d interfaces enable support for MME-SGSN (4G) mobility;
- S6a and Gr interfaces enable support for MME-SGSN (3G) mobility;
- Multiple Gr interfaces enable support for SGSN-SGSN mobility;
- S6 and SWx interfaces enable support for 3GPP to non-3GPP (4G) mobility;
- Gr and Wx interfaces enable support for 3GPP to WLAN (3G) mobility;
- S6a/S6d, S6t, S6m/S6n, S6t for CIoT/NB-IoT testing.
Execute timed chains of test events with a run-time command or during an automated test to trigger HSS-initiated procedures.
Emulator Configurations
One HSS Emulator can support any mixture of the interfaces shown in the diagram above, up to a maximum of 1000 client connections. 
Multiple HSS Emulators can be instantiated on a single server. In this mode each HSS Emulator can support multiple interfaces, up to an aggregate of 1000 client connections across all emulators. The HSS nodes are fully independent and their subscriber configurations may also be independent, may overlap, or may be duplicated.