Cisco ASR 5x00 Home eNodeB Instruction Manual

Cisco ASR 5x00 Home eNodeB Gateway
Administration Guide
Version 15.0
Last Updated September 30, 2013
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Cisco ASR 5x00 Home eNodeB Gateway Administration Guide
© 2013 Cisco Systems, Inc. All rights reserved.

Cisco ASR 5x00 Home eNodeB Gateway Administration Guide ▄
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CONTENTS
About this Guide................................................................................................v
Conventions Used................................................................................................................................... vi
Contacting Customer Support.................................................................................................................vii
Additional Information.............................................................................................................................viii
HeNB Gateway in Wireless LTE Network ........................................................9
Product Description................................................................................................................................10
Protocol Architecture..........................................................................................................................11
Deployment Scenarios for HeNB Access Network............................................................................13
HeNB Access Network Elements.......................................................................................................15
Home eNodeB ...............................................................................................................................15
Security Gateway (SeGW).............................................................................................................16
HeNB Gateway (HeNB-GW)..........................................................................................................16
HeNB Management System (HeMS).............................................................................................17
CSG List Server.............................................................................................................................17
Licenses.............................................................................................................................................17
Platform Requirements ......................................................................................................................17
Network Deployment and Interfaces......................................................................................................18
Supported Logical Interfaces .............................................................................................................18
Features and Functionality - Base Software ..........................................................................................21
AAA Server Group Support................................................................................................................21
Access Control List Support...............................................................................................................21
Bulk Statistics Support.......................................................................................................................22
DSCP Marking on S1-U Relay...........................................................................................................23
Fault Reporting Support.....................................................................................................................23
Location Reporting Support ...............................................................................................................23
QoS Support.......................................................................................................................................23
Redundancy Support..........................................................................................................................23
Troubleshooting Features Support.....................................................................................................24
Features and Functionality - Optional Enhanced Feature Software......................................................25
Automatic Neighbor Relation (ANR) Support.....................................................................................25
CSG-ID Based Paging Optimization Support ....................................................................................25
License-based Control for No. of HeNB Connections........................................................................26
License-based Control for No. of Subscribers Allowed......................................................................26
Understanding the Service Operation ...........................................................27
Terminology............................................................................................................................................28
Contexts.............................................................................................................................................28
Logical Interfaces...............................................................................................................................28
Bindings..............................................................................................................................................29
Services and Networks ......................................................................................................................29
HeNB-GW Service Configuration Procedures...............................................31
Information Required to Configure the System as an HeNB-GW..........................................................32
Required Local Context Configuration Information............................................................................32
Required Source Context Configuration Information.........................................................................32

▀Contents
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Required Destination Context Configuration Information...................................................................33
HeNB-GW Service Configuration...........................................................................................................37
HeNB-GW Service Configuration.......................................................................................................38
IPSec Configuration............................................................................................................................40
GTP-U Service Configuration.............................................................................................................41
LTE Policy Configuration....................................................................................................................42
Verifying HeNB-GW Configuration.....................................................................................................43
Logging Facility Configuration ................................................................................................................44
Displaying Logging Facility.................................................................................................................45
Alarm and Alert Trap Configuration........................................................................................................46
SNMP MIB Traps for HeNB-GW Service ...............................................................................................47
Event IDs for HeNB-GW Service............................................................................................................48
Monitoring the HeNB-GW Service..................................................................49
Monitoring System Status and Performance..........................................................................................50
Monitoring Logging Facility.....................................................................................................................53
Clearing Statistics and Counters............................................................................................................54
HeNB-GW Service Thresholds .......................................................................55
Saving Your Configuration......................................................................................................................56
System-Level HeNB-GW Service Thresholds........................................................................................57
Configuring System-level HeNB-GW Service Thresholds .................................................................57
Troubleshooting the Service ..........................................................................59
Test Commands .....................................................................................................................................60
Using the GTPU Test Echo Command ..............................................................................................60
Using the IPsec Tunnel Test Command.............................................................................................60
Using the SNMP TRAP command for debugging..............................................................................61
Using the RESOURCES SESSION command for debugging...........................................................61

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About this Guide
This document pertains to the features and functionality that run on and/or that are related to the Cisco® ASR 5000
Chassis.

About this Guide
▀Conventions Used
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Conventions Used
The following tables describe the conventions used throughout this documentation.
Icon
Notice Type
Description
Information Note
Provides information about important features or instructions.
Caution
Alerts you of potential damage to a program, device, or system.
Warning
Alerts you of potential personal injury or fatality. May also alert you of potential electrical hazards.
Typeface Conventions
Description
Text represented as a screen
display
This typeface represents displays that appear on your terminal screen, for example:
Login:
Text represented as commands
This typeface represents commands that you enter, for example:
show ip access-list
This document always gives the full form of a command in lowercase letters. Commands
are not case sensitive.
Text represented as a command
variable
This typeface represents a variable that is part of a command, for example:
show card slot_number
slot_number is a variable representing the desired chassis slot number.
Text represented as menu or sub-
menu names
This typeface represents menus and sub-menus that you access within a software
application, for example:
Click the File menu, then click New

About this Guide
Contacting Customer Support ▀
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Contacting Customer Support
Use the information in this section to contact customer support.
Refer to the support area of http://www.cisco.com for up-to-date product documentation or to submit a service request.
A valid username and password are required to access this site. Please contact your Cisco sales or service representative
for additional information.

About this Guide
▀Additional Information
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Additional Information
Refer to the following guides for supplemental information about the system:
Cisco ASR 5000 Installation Guide
Cisco ASR 5000 System Administration Guide
Cisco ASR 5x00 Command Line Interface Reference
Cisco ASR 5x00 Thresholding Configuration Guide
Cisco ASR 5x00 SNMP MIB Reference
Web Element Manager Installation and Administration Guide
Cisco ASR 5x00 AAA Interface Administration and Reference
Cisco ASR 5x00 GTPP Interface Administration and Reference
Cisco ASR 5x00 Release Change Reference
Cisco ASR 5x00 Statistics and Counters Reference
Cisco ASR 5x00 Gateway GPRS Support Node Administration Guide
Cisco ASR 5x00 HRPD Serving Gateway Administration Guide
Cisco ASR 5000 IP Services Gateway Administration Guide
Cisco ASR 5x00 Mobility Management Entity Administration Guide
Cisco ASR 5x00 Packet Data Network Gateway Administration Guide
Cisco ASR 5x00 Packet Data Serving Node Administration Guide
Cisco ASR 5x00 System Architecture Evolution Gateway Administration Guide
Cisco ASR 5x00 Serving GPRS Support Node Administration Guide
Cisco ASR 5x00 Serving Gateway Administration Guide
Cisco ASR 5000 Session Control Manager Administration Guide
Cisco ASR 5000 Packet Data Gateway/Tunnel Termination Gateway Administration Guide
Release notes that accompany updates and upgrades to the StarOS for your service and platform

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Chapter 1
HeNB Gateway in Wireless LTE Network
eNode B is the node with radio access capabilities in LTE radio access network (RAN) that is responsible for radio
transmission and reception from UEs in one or more in absence of Radio Network Controller (RNC) in LTE. The
functionality of eNode B is enhanced to handle the tasks which were handled by the RNC in the 3G network. The Home
eNode B (HeNB) provides LTE radio coverage for LTE devices/handsets within a home residential coverage area. An
HeNB incorporates the capabilities of a standard eNode B.
The Cisco® ASR5x00 provides LTE wireless carriers with a flexible solution that functions as a Home eNode B
Gateway (HeNB-GW) in HeNB Access Network to connect UEs with existing LTE networks.
The Home eNodeB Gateway works as a gateway for HeNBs to access the core networks. The HeNB-GW concentrates
connections from a large amount of HeNBs through S1 interface and terminates the connection to existing Core
Networks using standard interface.
This overview provides general information about the HeNB Gateway including:
Product Description
Network Deployment and Interfaces
Features and Functionality - Base Software
Features and Functionality - Optional Enhanced Feature Software

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Product Description
The Home eNodeB Gateway (HeNB-GW) or Femtocell Gateway (F-GW) is the HeNB network access concentrator
used to control capabilities necessary to manage large clusters of femtocells. It aggregates HeNBs or Femto Access
Points (FAPs) to a single network element and then integrates them into the Mobile Operators Voice, Data and
Multimedia networks. The primary function of HeNB-GW is to enable simple, seamless, and highly secure access to
subscribers as they roam between trusted/secure mobile networks and untrusted/unsecure public networks.
Femtocell is an important technology and service offering that enables new Home and Enterprise service capabilities for
Mobile Operators and Converged Mobile Operators. The Femtocell network consists of a plug-n-play customer premise
device generically called a Home eNodeB (HeNB) with limited range radio access in home or Enterprise. Femtocells’
biggest advantage is their capability to offload traffic from the macrocell networkand enable new applications, for
example: location based services.
The figure given describes a high level view of LTE network with Femtocell and HeNB-GW.
Figure 1. Home eNodeB Network Architecture
In the above figure, the S1 interface has been defined as an interface between
HeNB-GW and the Core Network (CN)/EPC
HeNB and the HeNB-GW
HeNB and the CN
An HeNB-GW provides standards-based S1-MME and S1-U network interfaces. As shown in the above high level LTE
Femto network architecture diagram, The HeNB-GW appears to the MME as an eNodeB. The HeNB-GW appears to
the HeNB as an MME. The S1 interface between HeNB and EPC whether the HeNB is connected to the CN/EPC via an
HeNB-GW or not. The HeNB-GW connects to the EPC in a way that inbound and outbound mobility to cells served by
the HeNB-GW does not necessarily require inter MME handovers.
In accordance with 3GPP LTE standards, the HeNB-GW hosts the following functions and procedures in LTE core
network:
Relaying UE-associated S1 application part messages between the MME serving the UE and the HeNB serving
the UE.
Terminating non-UE associated S1 application part procedures towards the HeNB and towards the MME.
Important: When an HeNB-GW is deployed, non-UE associated procedures shall be run
between HeNBs and the HeNB-GW and between the HeNB-GW and MME.

HeNB Gateway in Wireless LTE Network
Product Description ▀
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Optionally terminating S1-U interface with the HeNB and with the S-GW.
Supporting tracking area code (TAC) and PLMN ID used by the HeNB.
Allowing no X2 interface establishment between the HeNB-GW and other nodes.
Optionally performing paging optimization in case the Allowed closed subscriber group (CSG) List of the paged
UE is included in the PAGING message.
At the same time, the MME hosts the following functions to support HeNB-GW:
CSG reporting to S-GW/P-GW
Access control for UEs that are members of CSG
Optionally performing paging optimization
Important: Some of the features may not be available in this release. Kindly contact your local Cisco
representative for more information on supported features.
Protocol Architecture
This section provides a brief description and pictorial representation of protocol stacks for User as well as Control
planes in context to HeNB-GW.
Protocol Stacks for S1 User Plane
The S1-U data plane is defined between the HeNB, HeNB-GW and the S-GW. The figures below show the S1-U
protocol stack with and without the HeNB-GW.
Figure 2. User plane for S1-U interface for HeNB with HeNB-GW

HeNB Gateway in Wireless LTE Network
▀Product Description
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The HeNB-GW may optionally terminate the user plane towards the HeNB and towards the S-GW, and provide a relay
function for relaying User Plane data between the HeNB and the S-GW.
Protocol Stacks for S1 Control Plane
The two figures below show the S1-MME protocol stacks with and without the HeNB-GW. When the HeNB-GW is not
present, all the S1 procedures are terminated at the HeNB and the MME.
Figure 3. Control plane for S1-MME Interface for HeNB to MME without the HeNB-GW
The HeNB-GW terminates the non-UE-dedicated procedures: both with the HeNB, and with the MME. The HeNB-GW
provides a relay function for relaying Control Plane data between the HeNB and the MME. The scope of any protocol
function associated to a non-UE-dedicated procedure lies between HeNB and HeNB-GW, and/or between HeNB-GW
and MME.

HeNB Gateway in Wireless LTE Network
Product Description ▀
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Figure 4. Control plane for S1-MME Interface for HeNB to MME with the HeNB-GW
Any protocol function associated to a UE-dedicated-procedure resides within the HeNB and the MME only.
Deployment Scenarios for HeNB Access Network
An HeNB-GW can be deployed to provide an alternate path for the data traffic. It holds capabilities to divert the data
traffic away from core and directly onto the Internet thus reducing the load on the core network.
There are following two variants of deploying an LTE Femtocell Gateway (HeNB-GW) solution according to the TR
23.830:
Variant I: With dedicated HeNB-GW where HeNBs connect via HeNB-GW for control and data aggregation.
This deplyment scenario is displayed in the following figure:

HeNB Gateway in Wireless LTE Network
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1. With Dedicated HeNB-GW
Variant II:With HeNB-GW for conrol plane aggregation only and directly connect to SGW for data plane. This
deplyment scenario is displayed in the following figure:
2. With HeNB-GW for Control Plane

HeNB Gateway in Wireless LTE Network
Product Description ▀
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There is another deployment scenario for HeNBs where HeNB-GW is absent. In this deplyment, HeNBs connect
directly to highly scalable MMEs. This deplyment scenario is displayed in the following figure:
Figure 5. Without HeNB-GW
Cisco’s LTE Femtocell network solution focuses on Variant 1 where HeNB-GW is mandatory for HeNBs to connect.
Communication between the HeNB and the HeNB GW is secured by a security Gateway (SeGW) function. The SeGW
function is optionally collocated or else offloaded to external security function node.
HeNB Access Network Elements
This section provides the brief description and functionality of various network elements involved in the LTE Femtocell
access network. The HeNB access network includes the following functional entities:
Home eNodeB
Security Gateway (SeGW)
HeNB Gateway (HeNB-GW)
HeNB Management System (HeMS)
CSG List Server
Home eNodeB
A Home eNodeB (HeNB) is the a customer premise equipment that offers Uu interface to UE and S1 interface over
IPSec tunnel to HeNB-GW for accessing LTE Core Network in Femtocell access network.
It also provides the support to HeNB registration and UE registration over S1 interface with the HeNB-GW. Apart from
these functions HeNB also supports functions as given below:

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e-RAB management functions
Radio resource management functions
GTP-U tunnels management
Mobility management functions
Security functions
Service and Network access functions
Paging co-ordination functions
UE registration for HeNB
User-plane management functions including ciphering
Apart from the above listed basic functionalities, the HeNB is also involved in Mobility Management Entity (MME)
selection when no routing to an MME can be determined from the information provided by the UE. HeNB enforces the
UL (uplink) bearer level rate based on UE-AMBR and MBR via means of uplink scheduling; and does DL (downlink)
bearer level rate enforcement based on UE-AMBR (aggregate maximum bit rate).
Security Gateway (SeGW)
The Security Gateway is an logical function on HeNB-GW in the LTE femtocell network deployment, however it is
specified as a requirement in the Femtocell LTE network architecture. It may be implemented either as a separate
physical entity or co-located with an existing entity. The SeGW secures the communication from/to the HeNBs.
Basic function of this entity are:
Authentication of HeNBs
Termination of encrypted IPsec data connection from the femtocells
Providing access to HeMS and HeNB-GW
The SeGW holds capability of implementing a Denial of Service (DoS) shield to protect the EPC (S-GW and MME) by
detecting and then filtering out the attack traffic while maintaining the QoS (Quality of Service) of useful traffic. In our
implementation, it is an optional element which is situated on HeNB-GW.
HeNB Gateway (HeNB-GW)
The HeNB-GW provides the access to Femto user to LTE core network. It acts as an access gateway to HeNB and
concentrates connections from a large amount of HeNBs. HeNB-GW serves as a control plane (C-Plane) concentrator,s
pecifically the S1-MME interface.
The HeNB-GW may optionally terminate the user plane towards the HeNB and towards the S-GW, and may provide a
relay function for relaying User Plane data between the HeNB and the S-GW. The HeNB-GW supports NAS Node
Selection Function (NNSF).
Important: NAS Node Selection Function (NNSF)supports S1-Flex or multiple S1-MME connections
towards the EPC from any one HeNB.

HeNB Gateway in Wireless LTE Network
Product Description ▀
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HeNB Management System (HeMS)
It is a network element management system for HeNB access. Management interface between HeNB and HMS is based
on TR-069 family of standards. Femto access point extensions are based on standards as defined in TR-196.
It performs following functions while managing HeNB access network:
Facilitates HeNB-GW discovery for HeNB(s)
Provision of configuration data to the HeNB
Performs location verification of HeNB(s) and assigns appropriate serving elements (HeMS, SeGW, and HeNB-
GW)
The HeNB Management System (HMS) comprises of the following functional entities:
File Server: used for file upload or download, as instructed by TR-069 manager
TR-069 Manager: Performs CM, FM and PM functionality to the HeNB through Auto-configuration server
(HMS)
CSG List Server
The Closed Subscriber Group (CSG) List Server is an optional function which allows the EPC network to update the
allowed CSG lists on CSG-capable UEs.
The CSG List Server hosts functions used by a subscriber to manage membership to multiple as well as different CSGs.
For example, the CSG List Server includes the UE CSG provisioning functions which are responsible to manage the
Allowed CSG List and the Operator CSG list stored on the UE.
Licenses
The HeNB-GW is a licensed Cisco product. Separate session and feature licenses may be required. Each HeNB-GW
session corresponds to one IKEv2 session from an HeNB node when SeGW is integrated and enabled. The license is
based on the number of sessions and enables all HeNB-GW functionality, including the following:
IKEv2 support, including all IKEv2 and IPSEC encryption/authentication
HeNB-GW service
GTP-U service for S1-U data plane
Contact your Cisco account representative for detailed information on specific licensing requirements. For information
on installing and verifying licenses, refer to the Managing License Keys section of the Software Management
Operations chapter in the System Administration Guide.
Platform Requirements
The HeNB-GW service runs on a Cisco® ASR 5x00 chassis running StarOS Rel. 15.0 or later. The chassis can be
configured with a variety of components to meet specific network deployment requirements. For additional information,
refer to the Installation Guide for the chassis and/or contact your Cisco account representative.

HeNB Gateway in Wireless LTE Network
▀Network Deployment and Interfaces
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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.
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 and/or S-GW/P-GW in the same system.
These collocations are not yet supported in the Cisco ASR5x00 chassis and are planned for future 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:
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.
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.
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:

HeNB Gateway in Wireless LTE Network
Network Deployment and Interfaces ▀
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1. e-UTRAN Uu Interface Logical Representation
The physical layer in LTE is based upon the Orthogonal Frequency Division Multiplexing (OFDM) using
Orthogonal Frequency Division Multiple Access (OFDMA) in the downlink and variant of this Single Carrier
Frequency Division Multiple Access (SC-FDMA) in the uplink.
S1 Interface: The communication between the E-UTRAN and the EPC has been designated to the S1 interface.
The S1 interface has been separated by the Control plane signalling and User plane traffic:
S1-MME: The S1 variant used for Control plane signalling is referred to as S1-MME interface.
S1-U: The S1 variant used for User plane traffic is referred to as S1-U interface.
The S1-MME interface is governed by the S1-AP protocol, whose functions include:
E-RAB Management Function: This functionality is responsible for setting up, modifying and
releasing evolved Radio Access Bearers (E-RABs), which are triggered by the MME. The release of
E-RABs may be triggered by the eNodeB as well.
Initial Context Transfer Function: This functionality is used to establish an S1-UE context in the
eNodeB. It is also used to setup the default IP connectivity, to setup one or more E-RAB(s) if
requested by the MME, and to transfer NAS signalling related information to the eNodeB if needed.
UE Capability Information Indication Function: This functionality is used to provide the UE
Capability Information when received from the UE to the MME.
Paging: This functionality provides the EPC with the capability to page the UE.
S1 Interface Management Functions: These functions comprise the following:
Reset functionality for ensuring a well defined initialization on the S1 interface.
Error Indication functionality for allowing a proper error reporting/handling in cases where no
failure messages are defined.
Overload function for indicating the load situation in the control plane of the S1 interface.
Load balancing function for ensuring equally loaded MMEs within an MME pool area.
S1 Setup functionality for initial S1 interface setup for providing configuration information.

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eNodeB and MME Configuration Update functions are to update application level
configuration data needed for the eNodeB and MME to inter operate correctly on the S1
interface.
S1 UE context Release Function: This functionality is responsible to manage the release of UE
specific context in the eNodeB and the MME.
UE Context Modification Function: This functionality allows to modify the established UE Context
partly.
Status Transfer: This functionality transfers Packet Data Convergence Protocol (PDCP) SN Status
information from source eNodeB to target eNodeB in support of in-sequence delivery and duplication
avoidance for intra LTE handover.
Trace Function: This functionality is to control a trace session recording for a UE in
ECM_CONNECTED or to control an MDT (Minimization of Derive Tests) session transferring MDT
measurements collected by the UE.
Location Reporting: This functionality allows MME to be aware of the UE’s current location.
Warning Message Transmission Function: This functionality provides the means to start and
overwrite the broadcasting of warning message.
RAN Information Management (RIM) Function: This functionality allows the request and transfer
of RAN information (For example, GERAN system information) between two RAN nodes via the
core network.
Configuration Transfer Function: This functionality allows the request and transfer of RAN
configuration information (For example, SON information) between two RAN nodes via the core
network