ANSI/ITU SCCP Conversion Feature

Since some ANSI and ITU SCCP parameters are incompatible in format or coding, this feature provides a method for the EAGLE to convert these SCCP parameters in UDT, UDTS, XUDT, and XUDTS messages. Other types of SCCP messages (for example, XUDTS) are not supported and are discarded.

A specialized SCCP/TCAP conversion, introduced in EAGLE release 22.2 and used only in the Korean market, does not support this feature. The ANSI/ITU SCCP Conversion feature cannot be used with the EAGLE release 22.2 SCCP and TCAP Conversion features.

The ANSI/ITU SCCP Conversion feature provides a generic capability to correctly format and decode/encode these SCCP messages:

• UDT, UDTS, XUDT, and XUDTS messages. UDT and UDTS messages include SCMG messages, which are a specialized form of UDT messages.

• MTP routed SCCP messages.

• GT routed SCCP messages.

This feature also provides SCCP management (SCMG) across network type boundaries. For example, concerned signaling point codes for a mated application may be of a different network type than the primary point code of the mated application.

The ANSI/ITU SCCP Conversion is optional for ITU-X to ITU-Y domain crossing, where X and Y are different variants of ITU domains (ITU-I, ITU-N, ITU-I Spare and ITU-N Spare).

Advanced GT Modification

The Advanced GT Modification feature allows the deletion or substitution of digits from the beginning (prefix digit modification) or the end (suffix digit modification) of the global title address in either the called party address or the calling party address of the MSU. Prefix and suffix digit modifications are performed based on the prefix and suffix digit modification parameter values that are contained in the GT modification identifier that is assigned to the GTT, GTA, or GTT Actions entry. If the Advanced GT Modification feature is enabled, each GTT, GTA, or GTT Actions entry can specify either prefix digit modification, suffix digit modification, or both prefix and suffix digit modification. Refer to the Advanced GT Modification Feature section for more information on the Advanced GT Modification feature.

ANSI/ITU SCCP Conversion Feature Configuration

This feature requires that service modules are present in the EAGLE. Adding a Service Module shows the type of service modules that can be used depending on which features are on or enabled.

The parameter CNVCLGITU in SCCPOPTS makes the SCCP CGPA conversion optional for ITU-I to ITU-N domain crossing. The default value of this parameter is OFF when ANSI/ITU SCCP Conversion feature is turned on. If the feature is already ON, and the system is upgraded to Eagle 45.0, the default value is ON.

With the introduction of the parameter cgpcaction under the ent/chg-gta commands, CGPCACTION in GTA is applied regardless of whether the domain crossing was determined by GTT or not. Refer to Commands User's Guide for more details and options.

ITU-I to ITU-N SCCP CgPA conversion is optional for GTT related features only (GTT, GTT Actions, GTMOD and MAP SCRN). It is not applicable for services and subsystems that perform GTT on CgPA (GPORT, EIR, IDPR)

The ANSI/ITU SCCP Conversion feature must be enabled with the enable-ctrl-feat command, and turned on with the chg-ctrl-feat command. Perform the Activating the ANSI/ITU SCCP Conversion Feature procedure to enable and turn on the ANSI/ITU SCCP Conversion feature.

The concerned signaling point code (CSPC) group configuration has been changed to allow CSPC groups to contain ANSI (pc/pca), ITU-I or ITU-I spare (pci), and either 14-bit ITU-N or 14-bit ITU-N spare (pcn), or 24-bit ITU-N (pcn24) point codes. A CSPC group cannot contain both 14-bit and 24-bit ITU-N point codes. Concerned signaling point code groups are configured in the Adding a Concerned Signaling Point Code procedure.

The format of the point codes in the CSPC group assigned to a mated application, specified with the grp parameter, must be the same as the primary point code specified with the ent-map or chg-map commands only if the ANSI/ITU SCCP Conversion feature is not enabled. If the ANSI/ITU SCCP Conversion feature is enabled, the CSPC group may contain a mixture of point code types, and the network type of the CSPC group can be different from the network type of the primary point code of the mated application. Mated applications are configured in these procedures.

• Provisioning a Solitary Mated Application
• Provisioning a Dominant Mated Application
• Provisioning a Load Shared Mated Application
• Provisioning a Combined Dominant/Load Shared Mated Application
• Changing the Attributes of a Mated Application.

The conversion of ANSI and ITU SCCP messages is performed according to the options in the STP Options table, and by the entries contained in the default GT conversion table.

These options in the STP Options table control how this feature works.

:cnvcgda – The CGPA point code in ANSI SCCP messages are discarded if the point code or alias point code of the destination network type is not defined.

:cnvcgdi – The CGPA point code in ITU-I SCCP messages are discarded if the point code or alias point code of the destination network type is not defined.

:cnvcgdn – The CGPA point code in ITU-N SCCP messages are discarded if the point code or alias point code of the destination network type is not defined.

:cnvcgdn24 – The CGPA point code in ITU-N24 SCCP messages are discarded if the point code or alias point code of the destination network type is not defined.

:cnvclgitu – Allows for ITU-X to ITU-Y SCCP CGPA Conversion.

:gtcnvdflt – SCCP messages are routed using system defaults when an appropriate entry is not found in the Default GT Conversion Table.

The values for these options are either yes or no. If these options are set to yes, the actions defined by these options will be performed. These options are configured using the chg-stpopts command in the Changing the ANSI/ITU SCCP Conversion Options procedure.

Note:

If the value of the cnvcgda, cnvcgdi, or cnvcgdn options is no, and the calling party address of the MSU cannot be converted when the MSU is processed, then the MSU is discarded.

The Default GT Conversion Table contains the following items:

• The direction that the conversion takes place: ANSI to ITU, ITU to ANSI, or both directions.
• The global title indicator types being converted.
  • ANSI GTI type 2 to ITU GTI type 2
  • ANSI GTI type 2 to ITU GTI type 4
• The ANSI translation type
• The ITU translation type
• The numbering plan
• The nature of address indicator

The Default GT Conversion Table also provides for the provisioning of prefix or suffix address digit modification (refer to the Advanced GT Modification section. The Default GT Conversion Table is configured using either the ent-gtcnv command to add new entries to the Default GT Conversion Table (refer to the Adding a GT Conversion Table Entry procedure), or the chg-gtcnv command to change existing entries in the Default GT Conversion Table (refer to the Changing a GT Conversion Table Entry procedure).

The called party/calling party address indicator bit that is used when performing ANSI to ITU-N SCCP conversion is configured with the chg-sccpopts command. Perform the Configuring the ANSI to ITU-N SCCP Conversion Option procedure to select which called party/calling party address indicator bit will be used.

Note:

The called party/calling party address indicator bit in the MSU may be modified as soon as the ANSI/ITU SCCP Conversion is enabled and turned on, depending on the destination network of the MSU. If the MSU is sent to an ITU-I network, the value of the called party/calling party address indicator bit in the MSU may be changed to 0. If the MSU is sent to an ANSI or ITU-N network, the value of the called party/calling party address indicator bit in the MSU may be changed to 1. If you wish to set the value of the called party/calling party address indicator bit in the MSU after the ANSI/ITU SCCP Conversion is enabled and turned on, perform the Configuring the ANSI to ITU-N SCCP Conversion Option procedure.

Note:

The national indicator bit /international indicator bit for ANSI network or the ITU Reserved for National Use field (bit 8) within the calling party address/called party address indicator in the MSU may be modified as soon as the ANSI/ITU SCCP Conversion is enabled and turned on, depending on the destination network of the MSU. When an ANSI message is converted to an ITU message, the ITU Reserved for National Use field (bit 8) is set to the network associated with the post conversion DPC for MTP routed messages and the translated DPC for GT routed messages.

• If the DPC of the message is an ITU-N point code, then the ITU Reserved for National Use field is set to 1.
• If the DPC of the message is an ITU-I point code, then the ITU Reserved for National Use field is set to 0.

When an ITU message is converted to an ANSI message, the ANSI National/International Indicator (bit 8) is set to 1 (National).

If you wish to set the value of the Reserved for National Use bit (bit 8) in the calling party address/called party address indicator in the MSU after the ANSI/ITU SCCP Conversion is enabled and turned on, perform the Configuring the ANSI to ITU-N SCCP Conversion Option procedure.

Without the ANSI/ITU SCCP Conversion feature enabled, the domain of a GTT set must be the same as the domain of the GTI value of the GTT selectors. For example, an ANSI GTT set can be assigned to only ANSI GTT selectors and an ITU GTT set can be assigned to only ITU GTT selectors. When the ANSI/ITU SCCP Conversion feature is enabled a GTT set to be assigned to GTT selectors in both domains. This accomplished by creating a GTT set with the network domain of CROSS, a cross-domain GTT set. This allows the provisioning a single cross-domain GTT set with one set of GTA data and assign the cross-domain GTT set to multiple GTT selectors, regardless of their domain. The result is a GTT set that contains GTA data that can be used to translate both ANSI and ITU messages. Provisioning of the cross-domain GTT set is performed with the ent-gttset command. The EAGLE can contain more than one cross-domain GTT set. If the domain of the GTT set is either ANSI or ITU, the domain of a GTT set must be the same as the domain of the GTT selector. The domain of the GTT set can be changed from an ANSI GTT set or ITU GTT set to a cross-domain GTT set using the chg-gttset command. The EGTT feature must be turned on and the ANSI/ITU SCCP Conversion feature must be enabled to provision a cross-domain GTT set.

Alias Point Codes

For MTP routed SCCP messages, the message's DPC, OPC and CDPA must have alias point codes. The message's DPC, which is an alias, is converted to its true point code. The OPC is converted to its alias of the same network type as the DPC's true point code. If the message contains a CGPA PC, either it must have an alias of the same network type as the new DPC, or the Discard CGPA PC option for the original network type must be on.

For SCCP messages which receive GTT by the EAGLE, the message's DPC, OPC and CDPA are not converted and thus may not need alias point codes. The message's DPC is a result of GTT translation does not need conversion. The OPC is the EAGLE's OPC of the same network type as the DPC's network. If the message contains a CGPA PC, either it must have an alias of the same network type as the new DPC, or the Discard CGPA PC option for the original network type must be on.

For through-switched SCCP management messages, the message's DPC, OPC, and affected point code must have an alias of the destination network type.

For EAGLE originated SCCP messages, a mated application's PC(s) must have aliases of the same network types as the concerned point code group's PC(s).

Alias point codes are configured using the “Adding a Destination Point Code” procedure, for adding a new destination point code with an alias point code, or the “Changing a Destination Point Code” procedure, for changing the alias point code value for an existing destination point code. The “Adding a Destination Point Code” and “Changing a Destination Point Code” procedures are found in Chapter 2, Configuring Destination Tables in Database Administration - SS7 User's Guide.

Interaction with FLOBR/TOBR feature

All translations (CdPA GTA, CgPA GTA, CgPA PC, OPC, DPC, CgPA SSN, CdPA SSN and Opcode) support ANSI/ITU/CHINA SCCP Conversion feature. As a result of the ANSI/ITU/CHINA SCCP Conversion feature, the MSU can be routed to a different network domain. This is detected by comparing the incoming network domain against the network domain of the result of GTT (including GTT loadsharing).

ANSI/ITU/CHINA SCCP Conversion performs GTT on CgPA, one of 2 methods will be used:

• If the translation includes a CgPA Conversion Set (as defined by cgcnvsn parameter), then that set will be used with the CgPA GTA information from MSU to perform GTT in "CdPA-only" mode. Failure to locate translation information in the CgPA Conversion Set will fall back to Default Conversion GT information.
• If the translation does not include a CgPA Conversion Set, then CGPA selectors and GT digits from MSU will be used to perform GTT in CDPA only mode.

  Note:

  This is how OBSR is implemented; However, with FLOBR it is possible that the "CdPA-only mode" entry in the GTT Selector table is not CdPA GTT type, which will cause GTT on CgPA to fail.