In this section:
The terms CPU and VM may be used interchangeably.
Configuring the PC Formats
The DSC - SP2000 Platform supports MTP3 and GWST for ANSI and ITU networks. Both the MTP3 and GWST support multiple Network Appearances (NAs) in a single process and each NA has its own distinct SS7 Variant and associated PC Formats.
When linking a GWST record as a next step to another table and EPR record, both EPRs must be defined with the same PC Format (refer to GWST Tables).
There is no validation for the PC Format between GWST and MTP3. However, if an ANSI (for example, 8.8.8) message is received and accesses an ITU (for example, 3.8.3) Incoming Linkset, GWST returns a successful screening but a mismatch error message is logged.
Point codes are validated on a per screening table record basis. When creating a table record, the user can specify the PC format required to set this record’s PC Display or Routing format. The default PC format is used if the attribute is left empty. The default PC Display and Routing attributes should be changed if multiple records need to be created for a different network (refer to General Configuration).
Provisioning the GWST on a Distributed System
Each GWST process is distributed on both Routing and Management VMs of the DSC - SP2000 Platform for configurable data management. All screening and reporting data and batch operations are seamlessly distributed, updated on the system, and displayed in the UI.
GWST Provisioning Overview
Before you attempt to provision the GWST, it is recommended that you do the following:
- read this document and thoroughly understand the concepts and examples provided
- design the GWST process for the network before you attempt provisioning
- define the design criteria
- define the tables that are required for provisioning
- provision the table records in the appropriate order. Each table record must be provisioned separately.
The GWST screening process uses inter-related GWST tables in the following sequence (top-down):
- Incoming Linksets
- Incoming App IDs
- Allowed OPCs
- Blocked OPCs
- Allowed SIOs
- Allowed DPCs
- Blocked DPCs
- Affected (Allowed) Destinations
- Allowed ISUP Message Types
- Allowed TUP Message Types
- Allowed SCCP Calling Party Addresses
- Allowed SCCP Calling Digits Party Address
- Allowed SCCP Translation Types
- Allowed SCCP Called Digits Party Address
- Allowed SCCP Called Party Address
- Affected (Allowed) SCCP Managements
- Allowed TCAP Op Codes
- Allowed MAP IMSIs
If GTT is required on the incoming MSUs, any screening for SCCP Called (CLD) Party Address and SCCP subsystem management (SCMG) are processed after GTT.
Gateway redirection supports the following two tables that can be accessed from any of the screening tables:
- Redirect to App IDs
- Redirect to PCs
Redirect to PC can only be linked from tables processed before GTT.
Redirection records must already exist to be referenced by screening records.
The allowed tables are designed for the screening requirements but are also used for redirection. Typical redirection is based on specific criteria and the rest of the traffic should pass which is the reverse of the screening allowed definition. To simplify redirection provisioning and maintenance, allowed tables support a default record per entry point reference (EPR), which consists of all the record's attributes being set to their wildcard values. Default records do not trigger collision errors with existing records as they are only applied if no other record match exists.
The gateway accounting supports the following two tables that are handled independently from the screening and redirection tables:
- Accounting MTP3 Rules
- Accounting SCCP Rules
Accounting record can be correlated to either an SS7 linkset or a user with an Application ID on a given NA.
The gateway statistics supports the following table and is handled independently from any screening, redirection, or accounting tables:
- GWS Statistics Rules
GWST Provisioning Order
You must perform the GWST provisioning in the reverse order (bottom-up) to that of the order of the screening process. Accounting and statistics tables have no order requirement.
For example, if you are required to use the Incoming Linkset, Blocked OPC, and Allowed DPC screening tables, then the provisioning order would be
- Allowed DPC
- Blocked OPC
- Incoming Linkset
Deletion of screening records must be done in the same order as the screening process (top-down).