Cisco LTE PDN Gateway

Table Of Contents

Release Notes for Cisco LTE SPGW Gateway Release 2.0 on the Cisco SAMI,
Cisco IOS Software Release 12.4T4a

Contents

Cisco LTE SPGW Overview

LTE Evolved Packet Core

Cisco LTE SPGW Description

System Requirements

Memory Recommendations

Hardware and Software Requirements

Determining the Software Version

Upgrading to a New Software Release

MIBs

Limitations, Restrictions, and Important Notes

New and Changed Information

Caveats

Open Caveats

Cisco LTE SPGW

Cisco SAMI

Related Documentation

Release-Specific Documents

Platform-Specific Documents

Documentation Modules

Implementing a Cisco LTE SPGW on the Cisco SAMI

General Overview Documents

Documentation List by Task

Obtaining Documentation and Submitting a Service Request

Release Notes for Cisco LTE SPGW Gateway Release 2.0 on the Cisco SAMI,
Cisco IOS Software Release 12.4T4a

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March 30, 2011

Cisco LTE SPGW Release 2.0, Cisco IOS Release 12.4(24)T4a

This release note describes the requirements, dependencies, and caveats for the Cisco Long Term Evolution (LTE) Serving Gateway/PDN Gateway (SPGW) Release 2.0 on the Cisco Service and Application Module for IP (SAMI). These release notes are updated as needed.

For a list of the software caveats that apply to Cisco LTE SPGW, Cisco IOS Release 12.4(24)T4a releases, see the "Caveats" section and Caveats for Cisco IOS Release 12.4 T. The caveats document is updated for every maintenance release and is located on Cisco.com and the Documentation CD-ROM.

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Note Use these release notes with Cross-Platform Release Notes for Cisco IOS Release 12.4 located on Cisco.com and with the Cisco LTE SPGW Release 2.0 Configuration Guide and the Cisco LTE SPGW Release 2.0 Command Reference.

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Contents

This release note includes the following information:

•Cisco LTE SPGW Overview

•System Requirements

•MIBs

•Limitations, Restrictions, and Important Notes

•New and Changed Information

•Caveats

•Related Documentation

•Implementing a Cisco LTE SPGW on the Cisco SAMI

•Obtaining Documentation and Submitting a Service Request

Cisco LTE SPGW Overview

The following sections provide a brief overview of the Cisco LTE SPGW:

•LTE Evolved Packet Core

•Cisco LTE SPGW Description

LTE Evolved Packet Core

The Cisco LTE SPGW is a service designed for LTE Evolved Packet Core (EPC). The EPC is the main component of the System Architecture Evolution (SAE) that was designed by 3GPP to provide a migration path for 3GPP systems. The SAE is the core network architecture of LTE communication.

The SAE is an evolution of the General Packet Radio Service (GPRS) and Universal Mobile Telecommunication System (UMTS) core network that provides a migration path for 3GPP systems with the following differences:

•Simplified architecture

•All IP network

•Support for higher throughput and lower latency radio access networks (RANs)

•Support for and mobility between 3GPP (GPRS, UMTS, and LTE) and non-3GPP access technologies.

The LTE EPC is made up of the following primary elements:

•Mobility Management Entity (MME)

•Serving Gateway (SGW)

•Packet Data Network (PDN) Gateway (PGW)

Cisco LTE SPGW Description

The Cisco LTE SPGW is a Cisco IOS software feature that runs on the Cisco Service and Application Module for IP (SAMI) on the Cisco 7600 series platform. The Cisco LTE SPGW is a combined LTE serving gateway and LTE PDN gateway that supports GTP-based non-roaming and roaming architectures, and control and data plane functions defined by 3GPP TS 23.401 for 3GPP access networks. The SPGW can service SGW-only, PGW-only, GGSN, or SPGW sessions.

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Note For more information about the Cisco SAMI, see the Cisco Service and Application Module for IP User Guide.

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Cisco LTE SPGW Release 2.0 supports all of the features and interfaces supported by the Cisco LTE PDN Gateway and Cisco LTE Serving Gateway Release 1.0 and introduces the support for the following additional features:

•4 GB Cisco SAMI, which provides increased session and bearer density

•Dedicated bearers and associated QoS features, including flow-level QoS

•IPv6 transport for RADIUS-based interfaces

•N:M ratio of SPGW to CSG2, where N is not equal to M, with associated load balancing between the SPGW and CSG2.

•Lawful Intercept based on mobile station ISDN (MSISDN) and International Mobile Equipment Identity (IMEI) subscriber selection

•Subscriber and equipment session tracing using an external Tracing Collection Entity (TCE)

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Note Policy and Charging Enforcement Function (PCEF) and Gx functionality is provided by the Cisco Content Services Gateway - 2nd Generation (CSG2) running on a separate Cisco SAMI.

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Figure 1-1 shows the interworking (and interfaces) of the LTE SPGW with different radio access technologies.

Figure 1-1 LTE Network Components and Interfaces with the Cisco LTE SPGW on the Cisco SAMI in the Cisco 7600 Series Router

The following is a list of acronyms used in Figure 1-1.

•Serving GPRS Support Node (SGSN)

•GSM EDGE Radio Access Network (GERAN)

•Evolved UTRAN (E-UTRAN)

•Mobility Management Entity (MME)

•Serving Gateway (SGW)

•PDN Gateway (PGW)

•Charging Gateway Function (CGF)

•Home Subscriber Server (HSS)

•Policy and Charging Rules Function (PCRF)

•Online Charging System (OCS)

•Authentication, Authorization, and Accounting (AAA)

System Requirements

This section describes the system requirements for Cisco LTE SPGW Release 2.0 and includes the following sections:

•Memory Recommendations

•Hardware and Software Requirements

•Determining the Software Version

•Upgrading to a New Software Release

For hardware requirements, such as power supply and environmental requirements and hardware installation instructions, see the Cisco Service and Application Module for IP User Guide.

Memory Recommendations

Table 1 Images and Memory Recommendations for Cisco LTE SPGW Release 2.0

Platforms	Feature Sets	Software Image	Recommended Flash Memory (MB)	Recommended DRAM Memory (GB)	Runs From
Cisco SAMI/ Cisco 7600	SPGW Standard Feature Set	c7svcsami-l3ik9s-mz	128	4	RAM

Hardware and Software Requirements

Implementing a Cisco LTE SPGW Release 2.0 on the Cisco 7600 series Internet router platform requires the following hardware and software.

•Any module that has ports to connect to the network.

•A Cisco 7600 series router and one of the following supervisor engines running Cisco IOS Release 15.0(1)S or later:

–Cisco 7600 Series Supervisor Engine 720 with a Multiplayer Switch Feature Card 3 (WS-SUP720)

–Cisco 7600 Series Supervisor Engine 720 with a Multilayer Switch Feature Card 3 and Policy Feature Card 3B (WS-SUP720-3B)

–Cisco 7600 Series Supervisor Engine 720 with a Multilayer Switch Feature Card 3 and Policy Feature Card 3BXL (WS-SUP720-3BXL)

–Cisco 7600 Series Supervisor Engine 32 with a Multiplayer Switch Feature Card (WS-SUP32-GE-3B) with LCP ROMMON Version 12.2(121) or later on the Cisco SAMI.

–Cisco 7600 Series Supervisor Engine 32 with a Mutlilayer Switch Feature Card and 10 Gigabit Ethernet Uplinks (WS-SUP32-10GE-3B) with LCP ROMMON Version 12.2[121] or later on the Cisco SAMI.

Or one of the following Cisco 7600 series route switch processors running Cisco IOS Release 15.0(1)S or later

–Cisco 7600 Series Route Switch Processor 720 with Distributed Forwarding Card 3C (RSP720-3C-GE)

–Cisco 7600 Series Route Switch Processor 720 with Distributed Forwarding Card 3CXL (RSP720-3CXL-GE)

–Cisco 7600 Series Route Switch Processor 720 with 10 Gigabit Ethernet Uplinks with Distributed Forwarding Card 3CXL (RSP720-3CXL-10GE)

For details on upgrading the Cisco IOS release running on the supervisor engine, refer to the "Upgrading to a New Software Release" section in the Release Notes for Cisco IOS Release 15.0S. For information about verifying and upgrading the LCP ROMMON image on the Cisco SAMI, refer to the Cisco Service and Application Module for IP User Guide.

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Note The Cisco IOS software required on the supervisor engine is dependent on the supervisor engine being used and the Cisco mobile wireless application running on the Cisco SAMI processors.

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•Cisco Service and Application Module for IP (Cisco Product Number: WS-SVC-SAMI-BB-K9) with the Cisco SAMI 4 GB memory option (Cisco Product Number: MEM-SAMI-6P-4GB[=]). The Cisco SAMI must be running Cisco IOS Release 12.4(24)T4a or later.

•For security, the IPSec VPN Services Module.

•For enhanced service-aware billing support, an additional Cisco SAMI running the Cisco Content Services Gateway Second Generation software in each Cisco 7600 series router.

•For GTP-Session Redundancy (GTP-SR):

–In a one-router implementation, two Cisco SAMIs in the Cisco 7600 series router, or

–In a two-router implementation, one Cisco SAMI in each of the Cisco 7600 series routers.

Determining the Software Version

To determine the version of Cisco IOS software running on your Cisco SAMI, log in to PPC3 and enter the show version EXEC command:

SPGW# show version

Cisco IOS Software, SAMI Software (SAMI-L3IK9S-M), Experimental Version 
12.4(20100928:164957) 

Copyright (c) 1986-2010 by Cisco Systems, Inc.

Compiled Mon 28-March-11 09:49 by 

ROM: System Bootstrap, Version 12.4(20100716:044940) [sopm-smbu_lte_r1_5-CSCtf55588 105], 
DEVELOPMENT SOFTWARE

SPGW-Flash uptime is 22 hours, 14 minutes

System returned to ROM by reload at 22:43:43 UTC Mon March 28 2011

System restarted at 22:49:02 UTC Mon March 28 2011

System image file is "c7svcsami-l3ik9s-mz"

Last reload reason: Reload command by admin

...

SPGW# 

Upgrading to a New Software Release

For information on upgrading to a new software release, see the product bulletin Cisco IOS Software Upgrade Ordering Instructions at:

http://www.cisco.com/warp/public/cc/pd/iosw/prodlit/957_pp.htm

Upgrading the Cisco SAMI Software

For information on upgrading the Cisco SAMI software, see the Cisco Service and Application Module for IP User Guide:

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Note The image download process automatically loads the Cisco IOS image onto the six SAMI processors.

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MIBs

To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

Limitations, Restrictions, and Important Notes

When configuring the Cisco LTE SPGW, note the following:

•The Cisco LTE SPGW does not support the Cisco Express Forwarding (CEF) neighbor resolution optimization feature, which is enabled by default.

Therefore, to avoid the possibility of incomplete adjacency on VLAN interfaces for the redirected destination IP address and an impact to the upstream traffic flow for bearers/PDP sessions upon bootup, ensure that you configure the no ip cef optimize neighbor resolution command.

•The number of bearer/PDP contexts supported on the SPGW is dependent on the memory and platform in use and the SPGW configuration (for example, whether you are using Dynamic Feedback Protocol [DFP] or the memory protection feature is enabled, and what rate of bearer creation will be supported).

Table 1-2 lists the maximum number of sessions and bearers the Cisco SAMI with the 4 GB memory option can support:

Table 1-2 Number of Bearers/PDPs Supported in 4 GB SAMI

Session/Bearer Type	Maximum Number of Sessions	Maximum Number of Bearers
IPv4	846,000	1,776,600
IPv6	761,400	1,598,940
Ipv4v6	761,400	1,598,940

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Note When the maximum allowable number of bearers/PDP contexts is reached, the SPGW refuses new mobile sessions until sessions are available.

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•To avoid issues with high CPU usage, we recommend the following configurations:

–To reduce the CPU usage during bootup, disable logging to the console terminal by configuring the no logging console global configuration command.

–To ensure that the HSRP interface does not declare itself active until it is ready to process a peer's Hello packets, configure the delay period before the initialization of HSRP groups with the standby delay minimum 100 reload 100 interface configuration command under the HRSP interface.

–To minimize issues with high CPU usage for additional reasons, such as periods of high PPP PDP processing (creating and deleting), disable the notification of interface data link status changes on all virtual template interfaces of the GGSN using the no logging event link-status interface configuration command.

! 

interface Virtual-Template1 

description GGSN-VT 

ip unnumbered Loopback0 

encapsulation gtp 

no logging event link-status

gprs access-point-list gprs 

end 

•For Mobile Express Forwarding (MEF) support, you must configure the redirect all command under the APN.

•Ensure that radius-server source ports extended command is configured (to enable 200 ports in the range from 21645 to 21844 to be used as the source ports for sending out RADIUS requests). for more information about the radius-server source ports extended command, see the Cisco IOS Security Command Reference.

New and Changed Information

Cisco LTE SPGW Release 2.0 supports all of the features and interfaces the Cisco LTE PDN Gateway and Cisco LTE Serving Gateway Release 1.0 provide, plus introduces the support for the following additional features:

•4 GB Cisco SAMI, which provides increased session and bearer density

•Dedicated bearers and associated QoS features, including flow-level QoS

•IPv6 transport for RADIUS-based interfaces

•N:M ratio of SPGW to CSG2, where N is not equal to M, and with associated load balancing between the SPGW and CSG2.

•Lawful Intercept based on mobile station ISDN (MSISDN) and International Mobile Equipment Identity (IMEI) subscriber selection

•Subscriber and equipment session tracing using an external Tracing Collection Entity (TCE)

For a complete list of the features supported by the Cisco LTE PGW Release 1.x and Cisco LTE SGW Release 1.x, see the release notes for the Cisco IOS 12.4(24)T3c release of the Cisco LTE PGW and SGW.

Caveats

Caveats describe unexpected behavior in Cisco IOS software releases. Severity 1 caveats are the most serious caveats; severity 2 caveats are less serious. Severity 3 caveats are moderate caveats, and only select severity 3 caveats are included in the caveats document.

All caveats in Cisco IOS Release 12.4 and Cisco IOS Release 12.4 T are also in Cisco IOS Release 12.4(24)T4a.

For information on caveats in Cisco IOS Release 12.4, see Caveats for Cisco IOS Release 12.4.

For information on caveats in Cisco IOS Release 12.4 T, see Caveats for Cisco IOS Release 12.4T, which lists severity 1 and 2 caveats and select severity 3 caveats and is located on Cisco.com and the Documentation CD-ROM.

Using the Bug Navigator II

If you have an account with Cisco.com, you can use Bug Navigator II to find caveats the most current list of caveats of any severity for any software release. To reach Bug Navigator II, log in to Cisco.com and click Software Center: Cisco IOS Software: Cisco Bugtool Navigator II. Another option is to go directly to http://www.cisco.com/support/bugtools.

Open Caveats

This section contains the list of caveats that are open in Cisco LTE SPGW Release 2.0, Cisco IOS Release 12.4(24)T4a. The following sections document possible unexpected behavior and describe only severity 1 and 2 caveats and select severity 3 caveats.

•Cisco LTE SPGW

•Cisco SAMI

Cisco LTE SPGW

There are no known SPGW caveats are open in Cisco IOS Release 12.4(24)T4a.

Cisco SAMI

There are no known Cisco SAMI caveats are open with Cisco IOS Release 12.4(24)T4a.

Related Documentation

Except for feature modules, documentation is available as printed manuals or electronic documents. Feature modules are available online on Cisco.com.

Use these release notes with these documents:

•Release-Specific Documents

•Platform-Specific Documents

•Cisco IOS Software Documentation Set

Release-Specific Documents

The following documents are specific to Cisco IOS Release 12.4 and are located at Cisco.com:

•Cisco IOS Release 12.4 Mainline Release Notes

Documentation > Cisco IOS Software > Cisco IOS Software Releases 12.4 Mainline > Release Notes

•Cisco IOS Release 12.4 T Release Notes

Documentation > Cisco IOS Software > Cisco IOS Software Releases 12.4 T > Release Notes

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Note If you have an account with Cisco.com, you can use Bug Navigator II to find caveats of any severity for any release. You can reach Bug Navigator II on Cisco.com at http://www.cisco.com/support/bugtools.

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•Product bulletins, field notices, and other release-specific documents on Cisco.com at:

Documentation > Cisco IOS Software > Cisco IOS Software Releases 12.4 Mainline

Platform-Specific Documents

These documents are available for the Cisco 7600 series router platform on Cisco.com and the Documentation CD-ROM:

•Cisco Service and Application Module for IP User Guide

•Cisco 7600 series routers documentation:

–Cisco 7600 Series Internet Router Installation Guide

–Cisco 7600 Series Internet Router Module Installation Guide

–Cisco 7609 Internet Router Installation Guide

Cisco 7600 series router documentation is available at:

http://www.cisco.com/en/US/products/hw/routers/ps368/products_installation_guides_books_list.html

Cisco IOS Software Documentation Set

The Cisco IOS software documentation set consists of the Cisco IOS configuration guides, Cisco IOS command references, and several other supporting documents that are shipped with your order in electronic form on the Documentation CD-ROM, unless you specifically ordered the printed versions.

Documentation Modules

Each module in the Cisco IOS documentation set consists of two books: a configuration guide and a corresponding command reference guide. Chapters in a configuration guide describe protocols, configuration tasks, Cisco IOS software functionality, and contain comprehensive configuration examples. Chapters in a command reference guide list command syntax information. Use each configuration guide with its corresponding command reference. On Cisco.com at:

Documentation > Cisco IOS Software > Cisco IOS Software Releases 12.4 Mainline > Command References

Documentation > Cisco IOS Software > Cisco IOS Software Releases 12.4 Mainline > Command References > Configuration Guides

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Note To view a list of MIBs supported by Cisco, by product, go to: http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

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Implementing a Cisco LTE SPGW on the Cisco SAMI

The following sections list related documentation (by category and then by task) to use when you implement a Cisco LTE SPGW on the Cisco SAMI platform.

General Overview Documents

Core Cisco 7609 Router Documents

http://cisco.com/en/US/products/hw/routers/ps368/tsd_products_support_series_home.html

Documentation List by Task

For the most up-to-date list of documentation on the Cisco 7600 series router, refer to the Cisco 7600 Series Routers Documentation Roadmap on Cisco.com at:

http://cisco.com/en/US/docs/routers/7600/roadmaps/7600map.html

Getting Started

•Cisco 7600 Series Internet Router Essentials

http://cisco.com/en/US/products/hw/routers/ps368/products_quick_start09186a0080092248.html

•Regulatory Compliance and Safety Information for the Cisco 7600 Series Internet Routers

http://www.cisco.com/en/US/partner/docs/routers/7600/Hardware/RCSI/78_13690.html

Unpacking and installing the Cisco 7600 router:

•Cisco 7600 Internet Router Installation Guide

http://www.cisco.com/en/US/partner/docs/routers/7600/Hardware/Chassis_Installation/7600_Series_Router_Installation_Guide/pref.html

Installing the Supervisor module and configuring the router (basic configuration, such as VLANs, IP):

•Cisco 7600 Series Internet Router Module Installation Guides

http://www.cisco.com/en/US/partner/products/hw/routers/ps368/prod_installation_guides_list.html

•Cisco IOS Software Configuration Guide that applies to the latest release at the time of FCS

Installing and completing the Cisco SAMI configuration:

•Cisco 7600 Series Internet Router Module Installation Guides

http://www.cisco.com/en/US/partner/products/hw/routers/ps368/prod_installation_guides_list.html

•Cisco Service and Application Module for IP User Guide

http://www.cisco.com/en/US/docs/wireless/service_application_module/sami/user/guide/samiv1.html

Obtaining Documentation and Submitting a Service Request

For information on obtaining documentation, submitting a service request, and gathering additional information, see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation, at:

http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html

Subscribe to the What's New in Cisco Product Documentation as a Really Simple Syndication (RSS) feed and set content to be delivered directly to your desktop using a reader application. The RSS feeds are a free service and Cisco currently supports RSS Version 2.0.

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This document is to be used in conjunction with the Cisco GGSN Release 9.0 Configuration Guide and the Cisco GGSN Release 9.0 Command Reference publications.

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