Configuring Network Appearances

Overview

A Network Appearance (NA) is the appearance of a signaling node within an SS7 network. An NA may be identified by the point code (PC) of the node in this network.

The NA is represented within a DSC - SP2000 Platform as an integer. This integer is mostly of internal relevance to the DSC - SP2000 Platform, although in some cases, the integer may also have relevance to entities using the DSC - SP2000 Platform. Such entities may include Media Gateways which are referred to in the M3UA RFC 3332 as application servers.

A DSC - SP2000 Platform may support multiple NAs if the system

• supports SS7 networks with different Network Indicators (NIs) or SS7 Variants
• appears as a PC in more than one SS7 network
• has more than one PC in a single SS7 network

In this case, it may be necessary for the DSC - SP2000 Platform and any application servers to agree on the integer used to represent each NA.

Depending on your licensing arrangement, the DSC - SP2000 Platform supports the following NA configurations:

• For DSC Platforms:
  • if you have no Point Code Emulator (PCE), the system has one NA with value 1 created and activated by default and ready for configuration
  • if you have Basic PCE, the system has two NAs with values of 1 and 2 created and activated by default and ready for configuration
  • if you have Enhanced PCE, the system has three NAs with values of 1, 2 and 3 created and activated by default and ready for configuration
  • if you have a Level 4 Converter, the system has two NAs with values of 1 and 2 created and activated by default and ready for configuration
• For SP2000 Platforms:
  • if you have no Point Code Emulator (PCE), the system has one NA with value 1 created and activated by default and ready for configuration
  • if you have Basic PCE, the system has two NAs with integer values of 1 to 99 created and activated by default and ready for configuration
  • if you have Enhanced PCE, the system has three NAs with integer values of 1 to 99 created and activated by default and ready for configuration
  • if you have a Level 4 Converter, the system has two NAs with values of 1 and 2 created and activated by default and ready for configuration

In all cases, the system supports up to 32 NAs; therefore, you may create, activate, and configure up to 32 NAs for each system.

Depending on your license, you can configure the DSC - SP2000 Platform to function as either a Signaling Transfer Point (STP) or a Service Switching Point (SSP) End Node.

The Message Transfer Part Level 3 Broadband (MTP3B) feature allows a maximum message signal unit (MSU) length of 4092 Bits that includes the MTP3 routing label, SIO and the MTP user data. This MSU length applies to the ITU and ANSI protocols according to ITU Q.2210 and Telcordia GR-2878-Core and is supported for M2PA and M3UA link types.

MTP3B messages are forwarded to destinations that also support this MSU length. If a particular destination is not supported, then applicable alarms are raised and SNMP traps are sent. MTP3B support is configured at 

• NA (refer to Message Transfer Part Level 3 Broadband Support)
• Linkset (refer to Configuring MTP3B Support)
• M3UA User Registration (refer to SS7 Applications Guide 2)

The MTP2 Japanese Telecommunication Technology Committee (TTC) and Nippon Telegraph and Telephone Corporation (NTT) is designed to support four congestion levels (LEVEL 1, LEVEL 2, LEVEL 3, and FALSE). The MTP2 Japan TTC/NTT Protocol is only available when the SS7 Variant is set to TTC or NTT. To configure this feature, refer to Configuring Basic NA Attributes. For information about Japanese Networks, refer to Configuring Linksets and Links.

The following rules apply:

• Low Speed Links and M2PA Links are on the Japan network 
• Multiple link congestion levels are not supported on ATM and IPSP Link on Japan network
• Routeset congestion tests (RCTs) are only supported on TTC but not on NTT

The Process Event feature that appears in the UI, but is not described in this guide, provides an alarm type which ensures that the applications in all slots function as expected. With this feature, each application defines its own concept of functioning as expected, which means that the configuration/database files are synchronized and loaded, inter-peer connections are correctly established, and the peer applications are ready to process traffic.

If the application and its peer does not function as expected, an alarm is raised that is visible on the system's alarm panel. For more information about alarms, refer to the DSC Alarms Guide.

In accordance with GR-82-Core, Signaling Transfer Point (STP) Generic Requirements (A Module of FR-CCS-18), Issue 10, December 2006, the DSC - SP2000 Platform supports Memory Space Accounting (MSA). For more information about how this feature applies to Message Transfer Part Level 3 (MTP3), refer to the DSC - SP2000 Platform Manager User Guide.

NA Configuration Process

The NA configuration procedure includes the following tasks:

• define the NA type and NA attributes such as the local point code, SS7 Variant, and MTP Level 3 timer settings and so on. For an STP configuration, you can add Virtual Point Codes (VNodes). These procedures are documented within this section.
  
  
• define linksets to all adjacent point codes that the NA is directly connected to. Configure the operating parameters for each linkset and add your links to the linksets. For more information about configuring linksets and links, refer to Configuring Linksets and Links
  
  
• define routesets to the necessary destinations within the SS7 network. For each routeset, a set of routes must be specified, each corresponding to an existing linkset and having an associated relative cost (priority). For more information about routes and routesets, refer to Configuring Routesets and Routes.
  
  
• define VNodes as required. For more information about VNodes, refer to Configuring VNodes.