Important: Throughout this chapter the designation for the subscriber equipment is referred to in various ways: UE for user equipment (common to 3G/4G scenarios), MS or mobile station (common to 2G/2.5G scenarios), and MN or mobile node (common to 2G/2.5G scenarios involving IP-level functions). Unless noted, these terms are equivalent and the term used usually complies with usage in the relevant standards.
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• System Management Cards (SMCs): Provides full system control and management of all cards within the ASR 5000. Up to two SMCs can be installed; one active, one redundant.
• Packet Services Cards (PSCs): Within the chassis, PSCs (either PSC or PSC2) provide high-speed, multi-threaded PDP context processing capabilities for 2.5G SGSN, 3G SGSN, and GGSN services. Up to 14 PSCs can be installed, allowing for multiple active and/or redundant cards.
• Switch Processor Input/Outputs (SPIOs): Installed in the upper-rear chassis slots directly behind the SMCs, SPIOs provide connectivity for local and remote management, central office (CO) alarms, and BITS timing. Up to 2 SPIOs can be installed: 1 active, 1 redundant.
• Line Cards: Installed directly behind PSCs, these cards provide the physical interfaces from the SGSN to various elements in the GPRS/UMTS data network. Up to 26 line cards can be installed for a fully loaded system with 13 active PSCs, 13 in the upper-rear slots and 13 in the lower-rear slots for redundancy. Redundant PSCs do not require line cards.
• Redundancy Crossbar Cards (RCCs): Installed in the lower-rear chassis slots directly behind the SMCs, RCCs utilize 5 Gbps serial links to ensure connectivity between Ethernet 10/100 or Ethernet 1000 line cards/QGLCs and every PSC in the system for redundancy. Two RCCs can be installed to provide redundancy for all line cards and PSCs.Additional information, for each of the application and line cards required to support GPRS/UMTS wireless data services, is located in the ASR 5000 Hardware Installation and Administration Guide.Integrated co-location is done without introducing proprietary protocols, thus avoiding mobility and handoff issues. Multiple network element applications, integrated as a single application within a single chassis, benefit carriers for the following reasons:SGSNs and GGSNs work in conjunction within the GPRS/UMTS network. As indicated earlier in the section on System Configuration Options, the flexible architecture of the ASR 5000 enables a single chassis to reduce hardware requirements by supporting integrated co-location of a variety of the GPRS/UMTS services.
• IuPS: The SGSN provides an IP over ATM (IP over AAL5 over ATM) interface between the SGSN and the RNCs in the 3G UMTS Radio Access Network (UTRAN). RANAP is the control protocol that sets up the data plane (GTP-U) between these nodes. SIGTRAN (M3UA/SCTP) or QSAAL (MTP3B/QSAAL) handle IuPS-C (control) for the RNCs.
• Gb: This is the SGSN’s interface to the base station system (BSS) in a 2G radio access network (RAN). It connects the SGSN via UDP/IP (via an Ethernet interface) or Frame Relay (via a Channelized SDH or SONET interface). Gb-IP is the preferred interface as it improves control plane scaling as well as facilitates the deployment of SGSN Pools.
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• Gn/Gp: The Gn/Gp interfaces, comprised of GTP/UDP/IP-based protocol stacks, connect the SGSNs and GGSNs to other SGSNs and GGSNs within the same PLMN (the Gn) or to GGSNs in other PLMNs (the Gp).
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• Gr: This is the interface to the HLR. It supports SIGTRAN (M3UA/SCTP/IP) over Ethernet.
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• Ga: The SGSN uses the Ga interface with GTP Prime (GTPP) to communicate with the charging gateway (CG, also known as CGF) and/or the GTPP Storage Server (GSS). The interface transport layer is typically UDP over IP but can be configured as TCP over IP for:
• Gd: This is the interface between the SGSN and the SMS Gateway (SMS-GMSC / SMS-IWMSC) for both 2G and 3G technologies through multiple interface mediums. Implementation of the Gd interface requires purchase of an additional license.
• Gs: This is the interface used by the SGSN to communicate with the visitor location register (VLR) or mobile switching center (MSC) to support circuit switching (CS) paging initiated by the MSC. This interface uses Signaling Connection Control Part (SCCP) connectionless service and BSSAP+ application protocols.
• Gf: Interface is used by the SGSN to communicate with the equipment identity register (EIR) which keeps a listing of UE (specifically mobile phones) being monitored. The SGSN’s Gf interface implementation supports functions such as:The 2.5G and 3G SGSNs support a broad range of features and functionality - all fully compliant with 3GPP standards. The following is a list of some of the basic features supported by the SGSN:
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• Attached Idle Timeout - When enabled, if an MN has not attempted to setup a PDP context since attaching, this timer forces the MN to detach with a cause indicating that the MN need not re-attach. This timer is particularly useful for reducing the number of attached subscribers, especially those that automatically attach at power-on.
• Detach Prohibit - When enabled, this mechanism disables the Attached Idle Timeout functionality for selected MNs which aggressively re-attach when detached by the network.
• Prohibit Reattach Timer - When enabled, this timer mechanism prevents MNs, that were detached due to inactivity, from re-attaching for a configured period of time. Such MNs are remembered by the in-memory data-VLR until the record needs to be purged.
• Attach Rate Throttle - It is unlikely that the SGSN would become a bottleneck because of the SGSN’s high signaling rates. However, other nodes in the network may not scale commensurately. To provide network overload protection, the SGSN provides a mechanism to control the number of attaches occurring through it on a per second basis.Beside configuring the rate, it is possible to configure the action to be taken when the overload limit is reached. See the network-overload-protection command in the “Global Configuration Mode” chapter in the Command Line Interface Reference. Note, this is a soft control and the actual attach rate may not match exactly the configured value depending on the load conditions.
• MN Initiated Detach - The MN requests to be detached.
• SGSN Initiated Detach - The SGSN requests the MN to detach due to expiry of a timer or due to administrative action.
• HLR Initiated Detach - The detach initiated by the receipt of a cancel location from the HLR.
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• The SGSN’s 3GPP compliance for location management ensures efficient call handling for mobile users.For commands and information on network sharing configuration, refer to the Service Configuration Procedures section in the SGSN Administration Guide and the command details in the Command Line Interface Reference.
Refer to the SGSN APN Policy Configuration Mode chapter of the Command Line Interface Reference for the command to configure the GTPC private extension and refer to the IuPS Service Configuratioin Mode chapter of the Command Line Interface Reference to configure the LORC Cause IE.For NPU fast path configuration, refer to Enabling NPU Fast Path for GTP-U Processing section of “Service Configuration Procedures” chapter of SGSN Administration Guide.Unique, non-overlapping, IMSI + PLMN-ID ranges create call filters that are used to distinguish between the configured operator-policies. These filtering ranges are defined using the mcc command documented in the “SGSN Operator Policy Configuration Mode” chapter of the Command Line Interface ReferenceThe system supports up to 1000 operator policies, including the operator policy named default. All operator policies must be configured by the user to define limitations to be applied but for the default policy there is no mcc-command defined IMSI range filter to determine implementation - the default policy applies to any IMSIs that are not covered by any other defined operator policy.
• Refer to the SGSN Operator Policy Configuration Mode in the Command Line Interface Reference for the command to configure this feature.A pool area is a geographical area within which an MS/UE can roam without the need to change the serving CN node. A pool area is served by one or more CN nodes in parallel. All the cells, controlled by an RNC or a BSC belong to the same one (or more) pool area(s).For commands and information for VLR pooling configuration, refer to the “Gs Service Configuration Mode” chapter in the Command Line Interface Reference and the VLR Pooling in Service Configuration Procedure section in the SGSN Administration Guide.This data rate management per RNC functionality is enabled, in the radio network controller (RNC) configuration mode, by specifying the type of 3GPP release specific compliance, either release 7 for HSPA+ rates or pre-release 7 for HSPA rates. For configuration details, refer to the RNC Configuration Mode chapter in the Command Line Interface Reference.Refer to the SGSN APN Policy Configuration Mode chapter of the Command Line Interface Reference for the qos command.New fields and counters have been added to the output generated by the show subscribers gprs-only|sgsn-only summary command. This new information enables the operator to track the number of subscribers capable of GEA0-GEO3 and to easily see the number of subscribers with negotiated GEAx levels.For more information on Direct Tunnel configuration, refer to the SGSN Direct Tunnel Configuration chapter in the System Enhanced Feature Configuration Guide.Some commands for lawful intercept configuration and operations are described in the Command Line Interface Reference. For detailed information, please contact your account representative.
• Subscribed QoS - This is a per-APN configuration, obtained from the HLR on an Attach. It specifies the highest QoS allowed to the subscriber for that APN.
• Configured QoS - The SGSN can be configured with default and highest QoS profiles in the Operator Policy configuration.
• MS requested QoS - The QoS requested by the UE on pdp-context activation.
• PIR - Peak Information Rate (measured in bytes/second)
• CIR - Committed Information Rate (measured in bytes/second)
• PBS - Peak Burst Size (measured in bytes)
• CBS - Committed Burst Size (measured in bytes)For commands and information on traffic policing configuration, refer to the Traffic Policing and Shaping and Dynamic QoS Renegotiation chapter in the System Enhanced Feature Configuration Guide.
• Task recovery mode: One or more session manager failures occur and are recovered without the need to use resources on a standby packet processor card. In this mode, recovery is performed by using the mirrored “standby-mode” session manager task(s) running on active packet processor cards. The “standby-mode” task is renamed, made active, and is then populated using information from other tasks such as AAA manager.
• Full packet processor card recovery mode: Used when a PSC/PSC2 hardware failure occurs, or when a packet processor card migration failure happens. In this mode, the standby packet processor card is made active and the “standby-mode” session manager and AAA manager tasks on the newly activated packet processor card perform session recovery.For more information on session recovery use and session recovery configuration, refer to the Session Recovery chapter in the System Enhanced Feature Configuration Guide.For information on configuring and managing the SMS, refer to the SMS Service Configuration Mode chapter in the Command Line Interface Reference.
• RFC-1034, Domain Names - Concepts and Facilities, November 1987; 3GPP TS 24.008 v7.8.0 (2007-06)
• RFC-1035, Domain Names - Implementation and Specification, November 1987; 3GPP TS 23.003 v7.4.0 (2007-06)
• RFC-2960, Stream Control Transmission Protocol (SCTP), October 2000; 3GPP TS 29.202 v6.0.0 (2004-12)
• RFC-3332, MTP3 User Adaptation Layer (M3UA), September 2002; 3GPP TS 29.202 v6.0.0 (2004-12)
• RFC-4187, Extensible Authentication Protocol Method for 3rd Generation Authentication and Key Agreement (EAP-AKA), January 2006
• RFC-4666, signaling System 7 (SS7) Message Transfer Part 3 (MTP3) - User Adaptation Layer (M3UA), September 2006; 3GPP TS 29.202 v6.0.0 (2004-12)
• 3GPP TS 22.041 v8.1.0 (2007-06), 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Operator Determined Barring (ODB) (Release 8)
• 3GPP TS 23.060 v7.4.0 (2007-03), 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; General Packet Radio Service (GPRS); Service description; Stage 2
• 3GPP TS 23.107 v7.0.0 (2007-06), 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Quality of Service (QoS) concept and architecture
• 3GPP TS 23.236 v7.0.0 (2006-12), 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Intra-domain connection of Radio Access Network (RAN) nodes to multiple Core Network (CN) nodes (Release 7)
• 3GPP TS 23.251 v7.0.0 (2007-06), 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Network Sharing; Architecture and functional description
• 3GPP TS 24.008 v6.16.0 (2007-06), 3rd Generation Partnership Project; Technical Specification Group Core Network and Terminals; Mobile radio interface Layer 3 specification; Core network protocols; Stage 3; some features support v7.8.0 (2007-06) and v7.12.0 (2007-06)
• 3GPP TS 25.410 v6.5.0 (2006-03) and v7.0.0 (2006-03), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; UTRAN Iu Interface: general aspects and principles
• 3GPP TS 25.411 v7.0.0 (2006-03) and (2007-06), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; UTRAN Iu interface layer 1
• 3GPP TS 25.412 v7.1.0 (2006-06), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; UTRAN Iu interface signaling transport
• 3GPP TS 25.413 v6.14.0 (2007-06), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; UTRAN Iu interface RANAP signaling; some features support v7.6.0 (2007-06)
• 3GPP TS 25.414 v7.1.0 (2006-06), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; UTRAN Iu interface data transport & transport signaling
• 3GPP TS 25.415 v6.3.0 (2006-06), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; UTRAN Iu interface user plane protocols
• 3GPP TS 29.002 v6.15.0 (2006-12), 3rd Generation Partnership Project; Technical Specification Group Core Network and Terminals; Mobile Application Part (MAP) specification
• 3GPP TS 29.016 v6.0.0 (2004-12), 3rd Generation Partnership Project; Technical Specification Group Core Network and Terminals; Serving GPRS Support Node SGSN - Visitors Location Register (VLR); Gs Interface Network Service Specification
• 3GPP TS 29.018 v6.5.0 (2006-12), 3rd Generation Partnership Project; Technical Specification Group Core Network and Terminals; General Packet Radio Service (GPRS); Serving GPRS Support Node (SGSN) - Visitors Location Register (VLR) Gs interface layer 3 specification
• 3GPP TS 29.060 v6.17.0 (2007-06), 3rd Generation Partnership Project; Technical Specification Group Core Network and Terminals; General Packet Radio Service (GPRS); GPRS Tunnelling Protocol (GTP) across the Gn and Gp interface
• 3GPP TS 29.202 v8.0.0 (2007-06), 3rd Generation Partnership Project; Technical Specification Group Core Network; SS7 signaling Transport in Core Network; Stage 3
• 3GPP TS 32.215 v5.9.0 (2007-10), 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Telecommunication management; Charging management; Charging data description for the Packet Switched (PS) domain
• 3GPP TS 32.251 v7.4.0 (2007-10), 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Telecommunication management; Charging management; Packet Switched (PS) domain charging
• 3GPP TS 32.298 v7.4.0 (2007-10), 3rd Generation Partnership Project; Technical Specification Group Service and System Aspects; Telecommunication management; Charging management; Charging Data Record (CDR) parameter description
• 3GPP TS 33.102 v6.5.0 (2005-12), Technical Specification 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects;3G Security; Security architecture
• 3GPP TS 33.107 v6.4.0 (2004-12), 3rdGeneration Partnership Project; Technical Specification Group Services and System Aspects; 3G security; Lawful interception architecture and functions
• 3GPP TS 44.064 v7.1.0 (2007-03), 3rd Generation Partnership Project; Technical Specification Group Core Network; Mobile Station - Serving GPRS Support Node (MS-SGSN); Logical Link Control (LLC) layer specification
• 3GPP TS 48.014 v7.3.0 (2006-12), 3rd Generation Partnership Project; Technical Specification Group GSM EDGE Radio Access Network; General Packet Radio Service (GPRS); Base Station System (BSS) - Serving GPRS Support Node (SGSN) interface; Gb Interface
• 3GPP TS 48.016 v7.3.0 (2006-12), 3rd Generation Partnership Project; Technical Specification Group GSM EDGE Radio Access Network; General Packet Radio Service (GPRS); Base Station System (BSS) - Serving GPRS Support Node (SGSN) interface; Network Service
• 3GPP TS 48.018 v7.10.0 (2007-06), 3rd Generation Partnership Project; Technical Specification Group GSM/EDGE Radio Access Network; General Packet Radio Service (GPRS); Base Station System (BSS) - Serving GPRS Support Node (SGSN); BSS GPRS Protocol (BSSGP)
• Q711; 3GPP TS 29.002 v6.15.0 (2007-12), 3GPP TS 29.016 v7.0.0 (2007-08), and 3GPP TS 25.410 v7.0.0 (2006-03)
• Q712; 3GPP TS 29.002 v6.15.0 (2007-12), 3GPP TS 29.016 v7.0.0 (2007-08), and 3GPP TS 25.410 v7.0.0 (2006-03)
• Q713; 3GPP TS 29.002 v6.15.0 (2007-12), 3GPP TS 29.016 v7.0.0 (2007-08), and 3GPP TS 25.410 v7.0.0 (2006-03)
• Q714; 3GPP TS 29.002 v6.15.0 (2007-12), 3GPP TS 29.016 v7.0.0 (2007-08), and 3GPP TS 25.410 v7.0.0 (2006-03)
• Q715; 3GPP TS 29.002 v6.15.0 (2007-12), 3GPP TS 29.016 v7.0.0 (2007-08), and 3GPP TS 25.410 v7.0.0 (2006-03)
• Q716; 3GPP TS 29.002 v6.15.0 (2007-12), 3GPP TS 29.016 v7.0.0 (2007-08), and 3GPP TS 25.410 v7.0.0 (2006-03)
• Q771; 3GPP TS 29.002 v6.15.0 (2007-12)
• Q772; 3GPP TS 29.002 v6.15.0 (2007-12)
• Q773; 3GPP TS 29.002 v6.15.0 (2007-12)
• Q774; 3GPP TS 29.002 v6.15.0 (2007-12)
• Q775; 3GPP TS 29.002 v6.15.0 (2007-12)
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