Cisco Cisco Packet Data Interworking Function (PDIF)
HeNB Gateway in Wireless LTE Network
▀ Network Deployment and Interfaces
▄ HeNB-GW Administration Guide, StarOS Release 17
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Network Deployment and Interfaces
This section describes the supported interfaces and Cisco supported deployment scenario of HeNB-GW in LTE access
network.
network.
As mentioned above in the section “Deployment Scenarios for HeNB Access Network”, Cisco’s LTE Femtocell
network solution focuses on Variant 1 where HeNB-GW is mandatory for HeNBs to connect. HeNB-GW may also be
frequently deployed or co-located together with MME, S-GW/P-GW, and/or e-PDG in the same system.
network solution focuses on Variant 1 where HeNB-GW is mandatory for HeNBs to connect. HeNB-GW may also be
frequently deployed or co-located together with MME, S-GW/P-GW, and/or e-PDG in the same system.
These collocations are not yet supported in the Cisco ASR5x00 and virtualized platforms and are planned for future
releases.
releases.
Supported Logical Interfaces
This section provides the brief information on supported interfaces on HeNB-GW node.
In support of both mobile and network originated subscriber UE contexts, the HeNB-GW provides the following
network interface support:
network interface support:
E-UTRAN Uu Interface: The LTE Uu interface is responsible for all sort of signalling between UE and
eNodeB. It carries all signalling message between the eNodeB and the MME along with the user traffic
between the eNodeB and S-GW. This way the Uu interface works over both the Control as well as User planes.
between the eNodeB and S-GW. This way the Uu interface works over both the Control as well as User planes.
The protocols of the LTE Uu interface include:
Radio Resource Control (RRC): This protocol governs the signalling between the UE and MME.
Technically, the RRC governing lies between the UE and eNodeB. It terminates on the RAN access
equipment and then signalling is forwarded to MME.
equipment and then signalling is forwarded to MME.
Non-Access Stratum (NAS): This protocol also governs the signalling between UE and MME
Other than the above protocols, both the control planes (Control and User) of the Uu interface are supported by
the same set of interface functions. These interface functions include Security and Header Compression. All of
these functions are carried by the physical layer over the air as shown in the following figure:
the same set of interface functions. These interface functions include Security and Header Compression. All of
these functions are carried by the physical layer over the air as shown in the following figure: