Manual

Femtocell is an important technology and service offering that enables new Home and Enterprise service
capabilities for Mobile Operators and Converged Mobile Operators (xDSL/Cable/FFTH plus Wireless). The
Femtocell network consists of a plug-n-play customer premise device generically called a Home NodeB
(HNB) with limited range radio access in home or Enterprise. The HNB will auto-configure itself with the
Operators network and the user can start making voice, data and multimedia calls.
The figure given describes a high level view of UMTS network with Femtocell and HNB-GW.
Figure 1: HNB-GW Deployment in 3G UMTS Network
Once a secure tunnel has been established between the HNB and the SeGW and the HNB has been configured
by the HMS, the Operator has to connect the Femtocell network to their Core Network and services. There
are several interworking approaches to Circuit Switch (CS) and Packet Switch (PS) domains. One approach
is to make the Femtocell network appear as a standard Radio Access Network (RAN) to the Core Network.
In addition to the HNB, SeGW and HMS the RAN approach requires a network element generically called a
Femto Gateway (FGW/HNB-GW). The HNB-GW provides interworking and aggregation of large amount
of Femtocell sessions toward standard CN interfaces (IuPS/IuCS). In this approach services and mobility are
completely transparent to CN elements (e.g. MSC, xGSN).
The other approach is to connect the Femtocell to an IMS Network to provide CS services to subscribers when
on the Femtocell and deploy a new network element generically called a Convergence Server to provide
service continuity and mobility over standard interfaces at the MSC layer (e.g GSM-MAP, IS-41). These two
approaches are clearly different in how CS based services and mobility are achieved.
In accordance with 3GPP standard, the HNB-GW provides following functions and procedures in UMTS core
network:
•
HNB Registration/De-registration Function
•
UE Registration/De-registration Function for HNB
•
IuH User-plane Management Functions
•
IuH User-plan Transport Bearer Handling
HNB-GW Administration Guide, StarOS Release 19
2
HNB Gateway in Wireless Network
Product Description