SGSN Service Configuration Procedures

 

This chapter provides configure instructions to enable the system to operate as an SGSN in either GPRS (2.5G) or UMTS (3G) networks. Use this chapter in conjunction with the System Administration Guide to configure system-level features, such as interfaces. Commands to fine-tune or configure additional properties are provided in the Command Line Interface Reference.

High level step-by-step service configuration procedures are provided for the following:

•	2.5G SGSN Service Configuration

•	3G SGSN Service Configuration

•	Dual Access SGSN Service Configuration

Important: At least one Packet Services Card (PSC) must be activated prior to configuring the first service. PSC configuration procedures can be found in the System Administration Guide.

Detailed procedures are provided for the following:

•	Configuring an SS7 Routing Domain

•	Configuring an SS7 Routing Domain to Support Broadband SS7 Signaling

•	Configuring an SS7 Routing Domain to Support IP Signaling for SIGTRAN

•	Configuring GTT

•	Configuring an SCCP Network

•	Configuring a MAP Service

•	Configuring an IuPS Service (3G only)

•	Configuring an SGTP Service

•	Configuring a Gs Service

•	Configuring a GPRS Service (2.5G only)

•	Configuring an SGSN Service (3G only)

•	Configuring a Network Service Entity

•	Configure a Network Service Entity for IP

•	Configure a Network Service Entity for Frame Relay

•	Configuring DNS Client

•	Configuring SGSN Operator Policies

•	Configuring GTPP Accounting Support

 

2.5G SGSN Service Configuration

The following configuration steps must be completed to allow the system to operate in a 2.5G GPRS network.

The service handling the GPRS or 2.5G functions in the SGSN is called the “gprs-service”.

Step 1

Create all the contexts you will use in your configuration. Refer to the “System Element Configuration Procedures” chapter in the System Administration Guide.

Step 2

Create and configure the Frame Relay interface(s) and Ethernet interface(s). Refer to the “System Element Configuration Procedures” chapter in the System Administration Guide.

Step 3

Configure SS7 routing domains. Use the procedure in Configuring an SS7 Routing Domain.SS7 routing domain is not a standard SS7 concept. It is a concept specific to this platform which groups a set of SS7 feature configuration together to facilitate the management of the SS7 connectivity resources for an SGSN service.

Step 4

Configure GTT. The GTT configuration is used to set rules for GTT and define the GTT databases. Follow the procedure in Configuring GTT.

Step 5

Configure SCCP-Networks. The purpose of an SCCP network is to isolate the higher protocol layers above SCCP and the application itself from SS7 connectivity issues, as well as, to provide a place for global SCCP configuration specific to SGSN services. Use the procedure in Configuring an SCCP Network.

Step 6

Configure MAP services. The MAP service configuration is used by the SGSN service to communicate with many of the nodes on the narrow band-SS7 network part of the network such as HLR, EIR, GSM-SCF, GMLC and SMS-GMSC/SMS-IWMSC. The purpose of having an isolated map configuration is to enable different application services to use the map service to communicate with other map entities in the network. Use the procedure in Configuring a MAP Service.

Step 7

Configure SGTP. The SGTP service configures the parameters used for GTP Tunneling. At the minimum, interfaces for GTP-C and GTP-U must be configured. Use the procedure in Configuring an SGTP Service.

Step 8

Configure the SGSN service. All the parameters specific to the operation of an SGSN are configured in the SGSN service configuration mode. SGSN services use other configurations like MAP and IuPS to communicate with other elements in the network. The system can support multiple SGSN services. Use the procedure in Configuring an SGSN Service (3G only).

Step 9

Configure the GPRS service. All of the parameters needed for the system to perform as a an SGSN in a GPRS network are configured in the GPRS service. The GPRS service uses other configurations such as SGTP and MAP to communicate with other network entities and setup communications between the BSS and the GGSN. Use the procedure in Configuring a GPRS Service (2.5G only).

Step 10

Configure the Network Service Entity Instance. This identifies the NSEI to use and associates it with a Network Service Virtual Connection Identifier. Use the procedure in Configuring a Network Service Entity.

Step 11

Configure DNS. This configuration enables domain name resolution and specifies the DNSs to use for lookup. Use the procedure in Configuring DNS Client.

Step 12

Configure GTPP Accounting. This configures GTPP-based accounting for subscriber PDP contexts. Use the procedure in Configuring GTPP Accounting Support.

Step 13

Configure Frame Relay DLCI paths and bind them to NSEI links as needed. Refer to Creating and Configuring Frame Relay Interfaces and Ports in the SystemAdministration Guide..

Step 14

Save your configuration as described in the Verifying and Saving Your Configuration chapter.

 

3G SGSN Service Configuration

The following configuration steps must be completed to allow the system to operate in a 3G network.

Step 1

Create the contexts needed. Refer to the System Element Configuration Procedures chapter in the System Administration Guide.

Step 2

Create any interfaces needed in the appropriate context. Refer to the System Element Configuration Procedures chapter in the System Administration Guide for IP (broadcast Ethernet) interfaces and for ATM interfaces.

Step 3

Configure SS7 routing domains. The SS7 routing domain is proprietary concept to provide a combined configuration for the SS7 links, linksets, and related parameters. SS7 routing domain configurations are common to both SIGTRAN and MTP3-B networks. Use the procedure in Configuring an SS7 Routing Domain.

Step 4

Configure global title translations (GTT). The GTT configuration is used to set rules for GTT and to define the GTT databases. Follow the procedure in Configuring GTT.

Step 5

Configure SCCP networks. The SCCP network (layer) provides services to protocol layers higher in the SS7 protocol stack, for example RANAP and TCAP. The SCCP layer is also responsible for GTT . As well, all the SS7 routing domains (created in step 3) will be associated with an SCCP network. Use the procedure in Configuring an SCCP Network.

Step 6

Configure MAP services. The MAP service configuration is used by the SGSN service to communicate with many of the nodes in the SS7 network, such as the HLR, EIR, GSM-SCF, GMLC and SMS-GMSC/SMS-IWMSC. Having an isolated MAP configuration enables different application services to use the MAP service to communicate with other MAP entities in the network. Use the procedure in Configuring a MAP Service.

Step 7

Configure IuPS services. A set of parameters define the communication path between the SGSN service and radio network controllers (RNCs) in a UMTS IuPS service. Use the procedure in Configuring an IuPS Service (3G only).

Step 8

Configure SGTP services. The SGTP service configures the parameters used for GTP Tunneling. At a minimum, interfaces for GTP-C and GTP-U must be configured. Use the procedure in Configuring an SGTP Service.

Step 9

Configure the SGSN service. All the parameters specific to the operation of an SGSN are configured in the SGSN service configuration mode. SGSN services use other configurations like MAP and IuPS to communicate with other elements in the network. The system can support multiple SGSN services. Use the procedure in Configuring an SGSN Service (3G only).

Step 10

Configure DNS clients. This configuration enables domain name resolution and specifies the DNSs to use for lookup. Use the procedure in Configuring DNS Client.

Step 11

Optional: Configure SGSN operator policies. Operator policies are not required for SGSN operation, however, they provide the operator with a powerful method for determining call handling. SGSN operator policies specify rules governing the services, facilities and privileges available to a single subscriber or groups of subscribers. Use the procedure in Configuring SGSN Operator Policies.

Step 12

Configure GTPP Accounting. This configures GTPP-based accounting for subscriber PDP contexts. Use the procedure in Configuring GTPP Accounting Support.

Step 13

Configure ATM PVCs and bind them to interfaces or SS7 links as needed. Refer to Creating and Configuring ATM Interfaces and Ports in the SystemAdministration Guide.

Step 14

Save your configuration as described in the Verifying and Saving Your Configuration chapter.

 

Dual Access SGSN Service Configuration

The following configuration steps must be completed to allow the SGSN to operate in both GPRS (2.5G) and UMTS (3G) networks . This type of co-location is referred to as dual access.

To configure dual access requires a combination of steps from both the 2.5G and 3G configuration procedures:

Step 1

Create the contexts needed. Refer to the System Element Configuration Procedures chapter in the System Administration Guide.

Step 2

Create any interfaces needed in the appropriate context refer to the System Element Configuration Procedures chapter in the System Administration Guide:

Step a

For IP (broadcast Ethernet) interfaces, refer to Creating and Configuring Ethernet Interfaces and Ports in the SystemAdministration Guide..

Step b

For ATM interfaces (3G) refer to Creating and Configuring ATM Interfaces and Ports in the SystemAdministration Guide..

Step c

For Frame Relay interfaces (2.5G) refer to Creating and Configuring Frame Relay Interfaces and Ports in the SystemAdministration Guide..

Step 3

Configure SS7 routing domains. The SS7 routing domain is a non-standard, proprietary SS7 concept specific to this platform. SS7 routing domains provide a combined configuration for the SS7 links, linksets, and related parameters for SS7 connectivity resources for an SGSN service. SS7 routing domain configurations are common to both SIGTRAN and MTP3-B networks. Use the procedure in Configuring an SS7 Routing Domain.

Step 4

Configure global title translations (GTT). The GTT configuration is used to set rules for GTT and to define the GTT databases. Follow the procedure in Configuring GTT.

Step 5

Configure SCCP networks. The SCCP network (layer) provides services to protocol layers higher in the SS7 protocol stack, for example RANAP and TCAP. The SCCP layer is also responsible for GTT (step 4) and every SS7 routing domain (step 3) will be associated with an SCCP network. Use the procedure in Configuring an SCCP Network.

Step 6

Configure MAP services. The MAP service configuration is used by the SGSN service to communicate with many of the nodes in the SS7 network, such as the HLR, EIR, GSM-SCF, GMLC and SMS-GMSC/SMS-IWMSC. Having an isolated MAP configuration enables different application services to use the MAP service to communicate with other MAP entities in the network. Use the procedure in Configuring a MAP Service.

Step 7

Configure IuPS services. A set of parameters define the communication path between the SGSN service and radio network controllers (RNCs) in a UMTS IuPS service. Use the procedure in Configuring an IuPS Service (3G only).

Step 8

Configure SGTP services. The SGTP service configures the parameters used for GTP Tunneling. At a minimum, interfaces for GTP-C and GTP-U must be configured. Use the procedure in Configuring an SGTP Service.

Step 9

Configure the GPRS service. All of the parameters needed for the system to perform as a an SGSN in a GPRS network are configured in the GPRS service. The GPRS service uses other configurations such as SGTP and MAP to communicate with other network entities and setup communications between the BSS and the GGSN. Use the procedure in Configuring a GPRS Service (2G only).

Step 10

Configure the Network Service Entity Instance. This identifies the NSEI to use and associates it with a Network Service Virtual Connection Identifier. Use the procedure in Configuring a Network Service Entity.

Step 11

Configure DNS. This configuration enables domain name resolution and specifies the DNSs to use for lookup. Use the procedure in Configuring DNS Client.

Step 12

Configure GTPP Accounting. This configures GTPP-based accounting for subscriber PDP contexts. Use the procedure in Configuring GTPP Accounting Support.

Step 13

Configure ATM PVCs and bind them to interfaces or SS7 links as needed. Refer to Creating and Configuring ATM Interfaces and Ports in the SystemAdministration Guide.

Step 14

Configure Frame Relay DLCI paths and bind them to NSEI links as needed. Refer to Creating and Configuring Frame Relay Interfaces and Ports in the SystemAdministration Guide..

Step 15

Save your configuration as described in the Verifying and Saving Your Configuration section.

Configuring an SS7 Routing Domain

The SGSN supports both SS7- and IP-based routing. IP-based routing is provided through the use of contexts. SS7 routing is facilitated through the configuration and use of SS7 routing domains. SS7 routing domains group SS7-related configuration parameters. Depending on the SS7 signaling method, an SS7 routing domain may be configured with one of the following:

 

•

Linksets: Used for broadband SS7 signaling, linksets are comprised of link ids that specify point codes for SCCP endpoints. It is important to note that SCCP endpoints are further defined through the configuration of SCCP Networks (refer to Configuring an SCCP Network) which are associated with the SS7 routing domain in which the linkset is configured.

•	Application Server Processes (ASPs) / Peer Server Processes (PSPs): Used for IP (SIGTRAN), M3UA ASPs and PSPs dictate the IP address and port information used to facilitate communication between network endpoints. ASPs refer to the local endpoints.

 

Configuring an SS7 Routing Domain to Support Broadband SS7 Signaling

Step 1

In global configuration mode, create a new SS7 routing domain, give it a unique ID and specify the network variant that SS7 communications through this routing domain use.

Step 2

In SS7 routing domain configuration mode, configure the MTP-3 sub-service field (SSF).

Step 3

Create an SS7 linkset with a unique ID.

Step 4

In linkset configuration mode, specify the self point code - this is the point code of the SGSN.

Step 5

Specify the adjacent point code to communicate with another SS7 node, e.g., an RNC.

Step 6

Configure individual links, identified with link IDs.

Step 7

In link configuration mode, specify the MTP3 link priority.

Step 8

Specify the Signaling Link Code (SLC) for this link. This must be unique to this link within the current linkset. Note that SLCs must match, one-to-one, with those defined for the peer nodes.

Step 9

Configure this link to use either passive or active arbitration.

Step 10

In SS7 routing domain configuration mode, configure SS7 routes by specifying destination point codes and associated linkset IDs.

Example Configuration

configure

  ss7-routing-domain <id> variant <variant>

     ssf <subsvc>

     linkset id <id>

        self-point-code <#.#.#>

        adjacent-point-code <#.#.#>

        link id <id>

           priority <pri>

           signaling-link-code <code>

           arbitration <arbitration>

           exit

        exit

  route destination-point-code <dpc> linkset-id <id>

  end

 

Configuring an SS7 Routing Domain to Support IP Signaling for SIGTRAN

To configure IP, the SS7 routing domain must be configured in a specific way as described below:

Step 1

In Global configuration mode, create a new SS7 routing domain, give it a unique ID and specify the network variant that SS7 communications through this routing domain use.

Step 2

In SS7 Routing Domain configuration mode, configure the MTP-3 subservice field.

Step 3

Create an ASP (Application Service Part) instance for M3UA ASP configuration and give it a unique ID.

Step 4

Specify the local SCTP (Stream Control Transmission Protocol) end-point IP address and the name of the context where the IP interface associated with the address is configured.

Important: At least one address needs to be configured before the end-point can be activated.

Step 5

Specify the end-point SCTP port address to be used. Default port address is 2905.

Step 6

Bind the end-point to the application server process (ASP) instance to activate it.

Step 7

In SS7 routing domain configuration mode, create a peer server configuration with a unique ID.

Step 8

Name the peer server configuration. Usually this is the name of the SS7 network entity that this instance is configured to communicate with, for example an HLR, an STP, or an RNC.

Step 9

Specify the M3UA routing context ID.

Step 10

Create a PSP instance and give it a unique ID.

Step 11

In PSP configuration mode, specify the PSP mode in which this PSP instance should operate.

Step 12

Specify the communication mode this PSP instance should use as client or server.

Step 13

Configure the exchange mode this PSP instance should use. Generally this is not configured for IPSP-SG configuration, e.g., SGSN and STP.

Step 14

Configure the IP address of the peer node SCTP end-point for this PSP instance. At least one address needs to be configured before the end-point can be activated. Up to two addresses can be configured.

Step 15

Specify the ID of the ASP instance with which to associate this PSP instance.

Step 16

Configure SS7 routes, in SS7 routing domain configuration mode, by specifying destination point codes and peer server IDs. Routes are configured if the destination point code (DPC) is at least a hop away from the SGSN or when the DPC is not the same as the peer server. For example, the route is configured between the SGSN and the HLR which communicates through STPs or signaling gateways. In this case, the signaling gateways are configured as the peer server on the SGSN.

Example Configuration

configure

   ss7-routing-domain <id> variant <variant>

      ssf <subsvc>

      asp instance <instance_id>

         end-point address <address> context <ctxt_name>

         end-point bind

         exit

      peer-server id <id>

         name <name>

         routing-context <ctxt_id>

         psp instance <id>

            psp-mode <mode>

            exchange-mode <mode>

            end-point address <address>

            associate asp instance <id>

            exit

         exit

      route destination-point-code <dpc> peer-server-id <id>

   end

 

Configuring GTT

Global Title Translation (GTT) configuration consists of defining GTT associations, defining GTT address maps, and referring to these in an SCCP network configuration. The GTT Associations define GTT rules applicable to a specific GT format. The GTT Address Maps define a global title address to be routed to using a specific routing indicator. These are configured in the global configuration mode and are available to all SCCP networks configured in the system.

Step 1

In global configuration mode, create a GTT association with a unique name.

Step 2

In GTT association configuration mode, define the type of digit analysis to be used; “fixed” is the generally used digit analysis and if specified, also define the length of the digits to be analyzed. This is represented using action IDs.

Step 3

In GTT association configuration mode, define the GT format (1 to 4) for which the analysis needs to be applied.

Step 4

In the GT format configuration mode, specify the numbering plan and the nature of address to be used. Note that a separate GTT association needs to be created for a combination of numbering plan, nature of address, and GT format.

Important: There are many different ways to configure a GTT association and the needs of every network are different. Please refer to the Global Title Translation Association Configuration Mode chapter in the Command Line Interface Reference for the commands available.

Step 5

In global configuration mode, create a GTT address map, with a unique name, for a specific global title address.

Step 6

In GTT address map configuration mode, associate a specific GTT association and the action ID.

Step 7

In GTT address map configuration mode, define the routing indicator to be included in the Called-party Address in the out-going SCCP message along with the destination of the message using the option out-address.

Important: There are many different ways to configure a GTT Address Map and the needs of every network are different. Please refer to the GTT Address Map Configuration Mode chapter in the Command Line Interface Reference for the commands available.

Example Configuration

configure

   global-title-translation association instance <inst#>

      action id <id> type <action_type> start-digit <num> end-digit <num>

      gt-format <format_num>

         exit

      exit

   global-title-translation address-map instance <inst#>

      associate gtt-association <assoc#> action id <id>

      gt-address <gt_addr_prefix>

      out-address <name>

         ssf <sub_svc_fld>

         routing-indicator <route_ind>

         ni-indicator <addr_ind>

         ssn <sub_sys_num>

         point-code <pt_code>

         end

 

Configuring an SCCP Network

SCCP (Signaling Connection Control Part) networks are a concept specific to this platform. The SCCP network provides services to protocol layers higher in the SS7 protocol stack, e.g., RANAP and TCAP. This layer is also responsible for GTT. Every SS7 routing domain will be associated with an SCCP network. Use the following example configuration to specify a global SCCP configuration specific to SGSN services.

Important: A total of 12 SCCP networks can be configured.

To configure an SCCP network:

Step 1

In global configuration mode, specify an identification number for this SCCP network configuration and the signaling variant.

Step 2

Specify the self point code of the SGSN.

Step 3

Specify the SS7 routing domain with which to associate this SCCP network configuration.

Step 4

If using GTT (Global Title Translation), specify the name of a GTT address map to use.

Step 5

Configure a destination point code and give it a name.

Step 6

Configure the destination point code version.

Step 7

Configure the destination point code subsystem number.

Example Configuration

configure

   sccp-network <id_number> variant <v_type>

      self-pointcode <sp_code>

      associate ss7-routing-domain <rd_id>

      global-title-translation address-map <map_name>

      destination dpc <dp_code> name <name>

      destination dpc <dp_code> version <ver_type>

      destination dpc <dp_code> ssn <ss_number>

      end

 

Configuring a MAP Service

The Mobile Application Part (MAP) is an SS7 protocol which provides an application layer for the various nodes in GSM and UMTS mobile core networks and GPRS core networks to communicate with each other in order to provide services to mobile phone users. MAP is the application-layer protocol used to access the Home Location Register (HLR), Visitor Location Register (VLR), Mobile Switching Center (MSC), Equipment Identity Register (EIR), Authentication Center (AUC), Short Message Service Center (SMSC) and Serving GPRS Support Node (SGSN).

The primary facilities provided by MAP are:

 

•	Mobility Services: location management (when subscribers move within or between networks), authentication, managing service subscription information, fault recovery.

•	Operation and Maintenance: subscriber tracing, retrieving a subscriber's IMSI.

•	Call Handling: routing, managing calls while roaming, checking that a subscriber is available to receive calls.

•	Supplementary Services.

•	Short Message Service (SMS)

•	Packet Data Protocol (PDP) services for GPRS: providing routing information for GPRS connections.

•	Location Service Management Services: obtaining the location of subscribers.

Important: A maximum of 12 MAP services can be configured on the system.

To configure MAP services:

Step 1

In the context config mode, create a MAP service and give it a name.

Step 2

In MAP Service configuration mode, configure the SCCP network that defines SS7 connectivity for SCCP applications.

Step 3

Configure the parameters to contact the HLR.

Step 4

In HLR configuration mode, specify the HLR pointcodes that should be associated with specific IMSI prefixes.

Step 5

Configure the HLR pointcode to use as the default.

Step 6

Optional: Enable the Short Message Service functionality.

Step 7

Optional: Configure the SMS routing.

Example Configuration

configure

   context <context_name>

      map-service <map_name>

         access-protocol sccp-network <sccp_network_id>

         equipment-identity-register point-code <pnt_code>

         hlr

            imsi any point-code

            default policy routing

            exit

         short-message-service

            smsc-routing imsi-starts-with <prefix> point-code <sms_pc>

            end

 

Configuring an IuPS Service (3G only)

A set of parameters, in the IuPS service configuration mode, define the communication path between the SGSN service and the RNC. These configured parameters pertain to the RANAP layer of the protocol stack. IuPS services must be configured in the same context as the SGSN service that will use them.

To configure an IuPS service:

Step 1

In context configuration mode for the SGSN service, create an IuPS service and give it a unique name.

Step 2

In IuPS service configuration mode, specify the ID of the SCCP network to use for access protocol parameters.

Step 3

Bind an address of an IP interface defined in the current context to use for GTPU connections to the RNC.

Step 4

Specify an RNC to configure with a unique ID and the MCC and MNC associated with the RNC.

Step 5

In RNC configuration mode, specify the RNCs point code.

Step 6

Specify the LAC ID and RAC ID associated with the RNC.

Important: Appropriate interfaces (i.e., physical, loopback, secondary) must be defined prior to configuring the IuPS service or the GTP-U IP address will decline to bind to the service.

Example Configuration

configure

   context <context_name>

      iups-service <iups_name>

         access-protocol sccp-network <sccp_network_id>

         gtpu bind address <ip_address>

         rnc id <rnc_id> mcc <mcc_num> mnc <mnc_num>

            pointcode <rnc_pc>

            lac <lac_id> rac <rac_id>

            end

 

Configuring an SGTP Service

This section provides instructions for configuring GPRS Tunneling Protocol (GTP) settings for the SGSN. At a bare minimum, an address to use for GTP-C (Control signaling) and an address for GTP-U (User data) must be configured.

To configure the SGTP service:

Step 1

Create an SGTP service and give it a unique name, in context configuration mode.

Step 2

Specify the IP address of an interface in the current context to use for GTP-C.

Step 3

Specify the IP address of an interface in the current context to use for GTP-U.

Important: Appropriate interfaces (i.e., physical, loopback, secondary) must be defined prior to configuring the SGTP service or the GTP-U IP address will decline to bind to the service.

Example Configuration

configure

   context <name>

      sgtp-service <name>

         gtpc bind address <address>

         gtpu bind address <address>

         end

 

Configuring a Gs Service

This section provides instructions for creating and configuring a Gs interface used by the SGSN to communication with an MSC or VLR. The Gs interface is defined as a Gs service which handles the configuration for the MSC/VLR.

The Gs interface parameters are configured within a Gs service in a context. Then the Gs service is referred to in a GPRS service, an SGSN service, or an Operator Policy. The Gs service does not need to be in the same context as the SGSN service, GPRS service, or Operator Policy.

To configure the Gs service:

Step 1

In context configuration mode, create a Gs service and give it a unique name. Usually Gs service is defined in the same context in which MAP service is defined because the MSC/VLR, HLR, EIR, and SMS-C are reachable via the STP or SGW connected to the SGSN.

Step 2

Specify the name of the SCCP network that identifies the SS7 access protocols.

Step 3

Specify the target SS7 sub-system number (SSN), of the Base Station System Application Part (BSSAP), for communication. Without this bit of configuration, the Gs service can not start.

Step 4

Identify a location area code, in either a pooled or non-pooled configuration, relevant to the MSC/VLR. This step can be repeated as needed.

Step 5

Define the MSC/VLR by identifying its ISDN number, its SS7 point code, and the BSSAP SSN used to communicate with it. Repeat this step to define multiple MSC/VLRs. (Note: SSN only needs to be defined if the routing defined is to the MSC/VLR is PC+SSN.)

Example Configuration

configure

   context <name>

      gs-service <name>

         associate-sccp-network <id>

         bssap+ ssn <ssn>

         non-pool-area <id> use-vlr <vlr_id> lac <lac_id>

         vlr <vlr_id> isdn-number <isdn_number> bssap+ ssn <ssn> point-code <vlr_pt_code>

         end

 

Configuring an SGSN Service (3G only)

All the parameters specific to the operation of an SGSN in a UMTS network are configured in an SGSN service configuration. SGSN services use other configurations like MAP and IuPS to communicate with other elements in the network. The system can support multiple SGSN services.

To configure an SGSN service:

Step 1

In Context configuration mode, create an SGSN service and give it a unique name.

Step 2

Specify the Core Network (CN) ID that will identify this SGSN service on the CN.

Step 3

Specify the E.164 number to identify this SGSN service.

Step 4

Configure the maximum number of PDP contexts that a UE can establish.

Step 5

Specify the MAP service and the context in which it is configured that this SGSN service should use.

Step 6

Specify the IuPS service name and the context in which it is configured for the SGSN service to use for RAN protocol settings.

Important: GTP-U Direct Tunneling must be enabled in both the SGSN service and in the Operator Policy. Otherwise a direct tunnel will never be established.

Step 7

Specify the SGTP service and the context in which it is configured for this SGSN service to use for GTP configuration.

Step 8

Specify the CDR types that the SGSN service should generate.

Step 9

Specify the context in which GTPP accounting is configured. If the accounting context is not specified the current context is assumed.

Step 10

Configure the charging characteristics profile. (Number of buckets for the max change condition, volume limit, time limit, and tariff time switch values should be defined individually according to requirements for each of the charging characteristics profiles.

Step 11

Optional: Specify the Gs service name and the context in which it is configured.

Important: Session Management (SM) and GPRS Mobility Management (GMM) settings can be configured as needed using the SGSN configuration mode commands; <keyword> and <keyword. Refer to the SGSN Service Configuration Mode chapter in the Command Line Interface Reference.

Example Configuration

configure

   context <context_name>

      sgsn-service <svc_name>

         core-network id <cn_id>

         sgsn-number <sgsn_number>

         max-pdp-contexts per-ms <max_number>

         mobile-application-part service <map_name> context <map_context>

         ran-protocol iups-service <iups_svc_name> context <iups_context>

         sgtp-service <svc_name> context <name>

            accounting cdr-types [ mcdr | scdr ]

            accounting context <acct_context>

            cc profile <profile_number> interval <seconds>

            gs-service context <ctxt> service <gs_service_name>

            end

 

Configuring a GPRS Service (2.5G only)

 

All the parameters specific to the operation of an SGSN in a GPRS network are configured in a GPRS service configuration. GPRS services use other configurations like MAP and SGTP to communicate with other elements in the network. The system can support multiple GPRS services.

To configure a GPRS service:

Step 1

In Context configuration mode, create a GPRS service instance and give it a unique name.

Step 2

Specify the context in which the accounting parameters have been configured.

Step 3

Create a PLMN definition for the GPRS service to include the identity of the mobile country code (MCC) and the mobile network code (MNC).

Step 4

Associate other services (such as a MAP or Gs or SGTP service) and their configurations with this GPRS service. This command should be repeated to associate multiple service types and/or multiple instances.

Step 5

Define the network service entity identifier (NSEI) of one or more remote SGSNs with their location area code (LAC) and routing area code (RAC). This step can be repeated to associate multiple peer-NSEIs.

Step 6

Specify the E.164 number to identify this SGSN.

Step 7

Configure the charging characteristic(s).

Step 8

Specify the types of CDRs to generate.

Example Configuration

configure

   context <context_name>

      gprs-service <gprs_service_name>

         accounting <ctxt>

         plmn id mcc <mcc_num> mnc <mnc_num>

         associate-service <service_type> <service_id> context <service_ctxt>

         peer-nsei <peer_nsei_id> lac <lac_id> rac <rac_id>

         sgsn-number <sgsn_isdn_number>

         cc profile <id> buckets <value>

         cc profile <id> interval <value>

         accounting cdr-types <cdr_type>

         end

Configuring a Network Service Entity

 

Configure a Network Service Entity for IP

Prior to implementing this configuration, the IP interfaces should have been defined in the same context as the GPRS service.

Step 1

In Global configuration mode, create a network service entity (NSE) for IP. The resulting prompt will appear as:

[local]<hostname>(nse-ip-local)#

Step 2

In the Network Service Entity - IP local configuration mode, create up to four virtual links (NSVLs) for this entity - each with a unique NSVL Id. The resulting prompt will appear as:

[local]<hostname>(nse-ip-local-nsvl-<id>)#

Step 3

Configure the link access information: IP address, context name, and port number .

Step 4

Configure the links signaling characteristics.

Example Configuration for a Network Service Entity for IP

config

  network-service-entity ip-local -n

     nsvl instance <id>

        nsvl-address ip-address <ip_addr> context <ctxt> port <num>

           signaling-weight <num> data-weight <num>

           end

 

Configure a Network Service Entity for Frame Relay

Step 1

In Global configuration mode, create a network service entity (NSE) for Frame Relay. The resulting prompt will appear as:

[local]<hostname>(nse-fr-peer-nsei-id)#

Step 2

In the Peer NSEI configuration mode, create a virtual connection instance for this entity. The resulting prompt will appear as:

[local]<hostname>(nse-fr-peer-nsei-<id>-nsvci-<id>)#

Example Configuration for a Network Service Entity for IP

config

  network-service-entity peer-nsei <id> frame-relay

     ns-vc id <id> -n

end

 

Configuring DNS Client

DNS client services can be configured for a context.

Step 1

In context configuration mode, enable DSN lookup.

Step 2

Specify the DNS to use for lookups; maximum of two DNS addresses can be used.

Step 3

Create a DNS client with a unique name.

Step 4

In DNS Client configuration mode, bind the DNS client to the IP address of an interface in the current context.

Example Configuration

configure

   context <context_name>

      ip domain-lookup

      ip name-servers <ip_address>

      dns-client <name>

         bind address <ip_address>

         end

Configuring SGSN Operator Policies

An SGSN operator policy enables the operator to specify a policy with rules governing the services, facilities and privileges available to subscribers depending on factors such as roaming agreements between operators, the subscription restrictions for visiting or roaming subscribers, provisioning of defaults, and over-riding of standard behavior.

By configuring an operator policy, the operator fine-tunes any desired restrictions or limitations needed to control call handling per subscriber or for a group of callers within a defined IMSI range.

The system supports up to 1000 operator policies, including the operator policy named default. This default operator policy must be configured by the user to define limitations to be applied to any IMSIs that are not covered by any other defined operator policy.

 

Create an Operator Policy

The operator policy configuration that is applied is selected on the basis of the subscribers IMSI at attach time, and optionally the PLMN ID selected by the subscriber or the RAN node’s PLMN ID. Unique, non-overlapping, IMSI + PLMN-ID ranges are used to distinguish between the configured operator-policies. These are defined using the command in the SGSN Operator Policy Configuration Mode.

This configuration creates an SGSN operator policy with an IMSI range for filtering which calls should have this policy applied. Once created it can be modified at any time. .

Step 1

Create an operator policy.

Step 2

Configure the IMSI range to be used by the policy when determining which calls should be handled by this policy. The IMSI consists of the MCC (mobile country code), the MNC (mobile network code) and the mobile subscriber’s international number (MSIN).

Example Configuration

configure

   sgsn-operator-policy name <name>

      mcc <mcc_num> mnc <mnc_num> msin first <start_num> last <stop_num>

end

 

Access Limited to Home Subscribers

This configuration allows any subscriber from the home PLMN ID and restricts access to all others.

Step 1

Configure an operator policy corresponding to the home plmn-id.

Step 2

Configure the default operator policy.

Step 3

Set access restrictions in the default operator policy.

Example Configuration

configure

   sgsn-operator-policy name <name>

      mcc <mcc_num> mnc <mnc_num> msin first <start_num> last <stop_num>

      exit

   sgsn-operator-policy default

      attach restrict access-type umts all

      attach restrict access-type gprs all

      rau-inter restrict access-type umts all

      rau-inter restrict access-type gprs all

      end

 

PDP Activations Limited to Home Subscribers

In this configuration, any subscribers that don’t meet the requirements of the operator policy are filtered through the default policy where PDP activation rights are set.

Step 1

Configure an operator policy corresponding to the home plmn-id.

Step 2

Configure the default operator policy.

Step 3

Set access restrictions in the default operator policy.

Example Configuration

configure

   sgsn-operator-policy <name>

      mcc <mcc_num> mnc <mnc_num> msin first <start_num> last <stop_num>

      exit

   sgsn-operator-policy default

      pdp-activate restrict access-type umts all

      no pdp-activate restrict access-type gprs all

      end

 

Network Sharing Different PLMN-IDs for 3G and 2.5G UEs

This is a common deployment scenario where an operator has different plmn-ids configured for 3G and 2.5G access in the same radio network. The requirement is to consider the two plmn-ids as equivalent for purposes of cell selection/reselection and PLMN selection.

Step 1

Configure default SGSN operator policy.

Step 2

Configure the equivalent PLMN's list in the default operator policy.

Important: It is possible to have more complex combinations of access types and roaming restrictions while still allowing cell selection/reselection and PLMN selection by configuring specific operator policies instead of the default.

Example Configuration

configure

   sgsn-operator-policy default

      equivalent-plmn radio-access-technology 2G plmn-id mcc 123 mnc 333 priority 1

      equivalent-plmn radio-access-technology 2G plmn-id mcc 123 mnc 222 priority 2

      equivalent-plmn radio-access-technology 3G plmn-id mcc 123 mnc 333 priority 1

      equivalent-plmn radio-access-technology 3G plmn-id mcc 123 mnc 222 priority 2

      end

Network Sharing - Gateway Core Network (GWCN)

This section explains how to configure a common radio network shared by two core operators each with distinct PLMN IDs. Each operator has its own GGSN, DNS Servers and HLRs and exclusive contexts for each PLMN’s DNS & HLR configurations.

Configure an SGSN operator policy for each core operator and the dns-ggsn contexts and map-service in each operator policy.

Example Configuration

configure

   sgsn-operator-policy name operator-A

      mcc 123 mnc 111

      dns-ggsn context ctxtA

      sgtp-service context ctxt-A service map-A

      end

configure

   sgsn-operator-policy name operator-B

      mcc 456 mnc 321

      dns-ggsn context ctxt-B

      map-service context ctxt-B service map-B

      end

 

Specifying the MSC/VLR within an Operator Policy

This section explains how to configure an operator policy to specify the Gs service to use for communicating with an MSC/VLR.

Step 1

Enter Operator Policy Configuration mode for the desired operator policy.

Step 2

Specify the context in which the desired Gs service is configured and the specific Gs service name.

Example Configuration

configure

   sgsn-operator-policy name <name>

      gs-service context <ctxt> service <gs_service_name>

      end

 

Enabling NPU Fast Path for GTP-U Processing

This configuration enables the NPU processed Fast Path feature on SGSN to enhance the GTP-U data processing at the NPU level only.

Important: This functionality is only available on an ASR 5000 platform.

To configure the NPU Fast Path for an SGSN operator policy:

Step 1

Create the SGSN operator policy by applying the example configuration in the Creating an SGSN Operator Policy section.

Step 2

Enable the Fast Path the charging agent and GTPP server (CGF) related parameters for the GTPP accounting support by applying the example configuration in the Configuring GTPP Accounting Support section.

Step 3

Save your configuration as described in the Saving Your Configuration chapter.

Creating an SGSN Operator Policy

Use the following example to create the SGSN operator policy for SGSN subscribers:

configure

   sgsn-operator-policy name <sgsn_policy_name> [ -noconfirm ]

      end

Notes:

 

•	<sgsn_policy_name> is the name of the operator policy to configure for control of the SGSN service access based on service operators discretion.

Enabling NPU Fast Path

Use the following example to enable the NPU fast path feature in an operator policy for SGSN subscribers:

configure

   sgsn-operator-policy name <sgsn_policy_name>

      gtpu fast-path

      end

Notes:

 

•	<sgsn_policy_name> is name of the Operator policy already configured on the system.

 

Configuring GTPP Accounting Support

This section provides instructions for configuring GTPP-based accounting which allows the SGSN to send M-CDR and/or S-CDR accounting data to the Charging Gateways (CGs) over the Ga interface.

The Ga interface and GTPP functionality are typically configured within a separate charging context.

The SGSN begins to generate M-CDR data upon GPRS/IMSI attach. S-CDR data generation begins upon PDP context activation.

Accounting servers can be configured individually or as GTPP accounting server groups. GTPP accounting server groups can each have completely different GTPP settings configured. Although a GTTP server can be included in multiple GTPP groups.

Any GTPP accounting servers configured at the context level that are not specifically configured as part of a GTPP group, are automatically assigned to be part of the GTPP server group called default that is part of every context.

A maximum of 8 GTPP named server groups can be configured across all contexts. A maximum of 4 CGFs can be configured in each GTPP server group. A total of total 32 CGFs can be configured across all server groups, including the server group called default, in one context. Each GTPP group must have unique GTPP charging agents (CGFs) configured.

Important: The system supports the specification of the UDP port number for the charging agent function on the system and for the CG. The default charging agent port is 49999. The default CG Server port is (3386). If an SGSN service and a GGSN service are both configured on this system be sure that the UDP ports are unique for each type of service. Refer to the Command Line Interface Reference for information on changing the ports used.

To configure the GTPP accounting support for a SGSN service:

Step 1

Create the GTPP group in accounting context by applying the example configuration in the Creating GTPP Group section.

Step 2

Configure the charging agent and GTPP server (CGF) related parameters for the GTPP accounting support by applying the example configuration in the Configuring GTPP Group section.

Step 3

Verify your GTPP group and accounting configuration by following the steps in the Verifying GTPP Group Configuration section.

Step 4

Save your configuration as described in the Verifying and Saving Your Configuration chapter.

Creating GTPP Group

Use the following example to create the GTPP group to support GTPP accounting:

configure

  context <vpn_ctxt_name>

     gtpp group <gtpp_group_name> -noconfirm

     end

Notes:

 

•	In addition to one default GTPP group “default” a maximum of 8 GTPP groups can be configured with this command in a context.

•	In case no GTPP group is configured in this context, system creates a default GTPP group named “default” and all the CGF servers and their parameters configured in this context are applicable to this “default” GTPP group.

Configuring GTPP Group

Use the following example to configure the GTPP server parameters, GTPP dictionary, and optionally CGF to support GTPP accounting:

configure

  context <vpn_ctxt_name>

     gtpp group <gtpp_group_name>

        gtpp charging-agent address <ip_address> [ port <port> ]

        gtpp server <ip_address> [ max <msgs >] [ priority <priority>]

        gtpp dictionary <dictionaries>

        gtpp max-cdrs <number_cdrs> [ wait-time <dur_sec> ]

        gtpp transport-layer { tcp | udp }

        end

Notes:

 

•	In addition to one default GTPP group “default” a maximum of 8 GTPP groups can be configured with this command in a context.

•	In case no GTPP group is configured in this context, system creates a default GTPP group named “default” and all the CGF servers and their parameters configured in this context are applicable to this “default” GTPP group.

•	Command for CGF gtpp charging-agent is optional and configuring gtpp charging-agent on port 3386 may interfere with ggsn-service configured with the same ip address. Multiple interfaces can be configured within a single context if needed.

•	For more information on GTPP dictionary encoding in addition to referring Command Line Interface Reference, refer AAA Interface Administration and Reference.

•	For better performance, it is recommended to configure maximum number of CDRs as 255 with gtpp max-cdrs command.

•	You can select transport layer protocol as TCP or UDP for Ga interface with gtpp transport-layer command. By default it is UDP.

•	Multiple GTPP server can be configured using multiple instances of this command subject to following limits:

•	Total 4 GTPP server in one GTPP group

•	Total 32 GTPP server in one context

•	Total 9 GTPP groups (1 default and 8 user defined GTPP groups) can be configured in one context. Number of CGFs in 1 GTPP group is limited to 4 and a total of 32 CGF servers across all GTPP groups in one context are configurable.

 

Verifying GTPP Group Configuration

Step 1

Verify that your CGFs were configured properly by entering the following command in Exec Mode:

 

show gtpp accounting servers

This command produces an output similar to that displayed below:

 

context: source

Preference   IP                Port   Priority     State         Group

----------  ---------------    ----   --------    -------       ------

Primary     192.168.32.135     3386          1     Active       default

Primary     192.168.89.9       3386        100     Active       default

Creating and Configuring ATM Interfaces and Ports (3G only)

ATM ports and their associated PVCs can be configured for use with point-to-point interfaces and defined in a context or they can be bound to link IDs defined in SS7 routing domains.

Refer to the chapter titled System Element Configuration Procedures in the System Administration Guide for information on configuring ATM interfaces.

Creating and Configuring Frame Relay Ports (2.5G only)

Frame Relay ports and their associated DLCIs can be configured for communication with 2G Base Station subsystem (BSS) for an SGSN implementation.

Refer to the chapter titled System Element Configuration Procedures in the System Administration Guide for information on configuring Frame Relay ports.

 

 

 

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