You are here: CSP Developer’s Guide: Common Channel Signaling > 3 SS7 over the EXNET® Ring > Configuring SS7 Over the Ring

Configuring SS7 Over the Ring

Purpose

This section describes the procedure for bringing SS7 over the ring into service. It assumes that all hardware configuration and cabling is complete, that all nodes are powered up, and that a host-to-node communication link has been established.

The CSP Developer’s Guide: Overview provides detailed setup procedures for downloading system software, for establishing socket connections and for configuring rings and nodes.

Before you begin

With SS7 over the ring, the CCS Redundancy Configure (0x5B) message will take at least 50 seconds before the ACK is returned, assuming there is no call processing.

To ensure that SS7 over the ring is operational before configuration starts, do the following:

1 Modify the application, as required, to support SS7 control of CICs in multiple chassis/nodes that have a single Originating Point Code (OPC) in the Server Node.

2 Move signaling links to the SS7 Server Node. Change the configuration as required.

3 Insert a new, RISC-based SS7 card(s) into the SS7 Server Node

4 Install the CCS I/O cards, with the CCS I/O Redundancy Cable (see CCS I/O Redundancy Cable Installation and Removal" in the Hardware Installation and Maintenance Manual).

5 Execute the Configuration Procedure for SS7 over the ring.

Guidelines

When you configure SS7 over the ring, perform the steps below, and use these steps as a guideline to your initial configuration.

All SS7 configuration messages must be sent to the node that contains the SS7 card(s).

Configuration Procedure

Follow the procedure below to configure SS7 over the ring.

1 Assign the logical node ID.

Send the Assign Logical Node ID message (0x10), using the serial number of the CSP chassis number as the physical node ID.

2 Assign logical spans throughout the CSP.

Send the Assign Logical Span ID message (0xA8) to assign spans to physical span offsets from EXNET®.

3 Configure the spans and channels corresponding to SS7 signaling links for clear channel.

Send either the E1 Span Configure message (0xD8) or the T1 Span Configure message (0xA9), depending on the protocol you use, to establish clear channel signaling.

4 Assign the SS7 cards as either primary or secondary (optional).

Send the CCS Redundancy Configure message (0x5B) if you are using a redundant card pair.

No CSP-specific configuration is required.

5 Configure the SS7 Signaling Stacks with a stack ID, an Originating Point Code (OPC), and the variant to be used.

Send the SS7 Signaling Stack Configure message (0x5C) to assign the stack ID, OPC, and variant.

6 Configure the signaling link sets with a signaling link set ID to a given adjacent point code.

Send the SS7 Signaling Link Set Configure message (0x5D) to configure the link sets.

No CSP-specific configuration is required.

7 Configure the signaling links with the logical span/channel.

Send the SS7 Signaling Link Configure message (0x5E) to configure the links. The timeslot is provided off the local bus.

8 Configure the signaling routes and specify the relationship between a remote Destination Point Code (DPC) and the signaling links capable of reaching DPC.

Send the SS7 Signaling Route Configure message (0x5F) to configure the routes.

No CSP-specific configuration is required.

9 Assign the voice circuits and associate a set of span/channels with a set of Circuit Identification Codes (CICs) for a particular stack ID.

Send the SS7 CIC Configure message (0x6A) to configure CICs.

Based on the logical span ID, the node that owns the logical span is informed that the stack ID controlling the voice circuits is the stack assigned to control the CICs in the message.

10 Send Service State Configure for each of the following:

• To bring: the spans into service.

• To bring the SS7 links into service.

• To bring the channels (CICs) into service.

Communication between SS7 stacks and CSP Call Control components

The remote nodes know which stacks are controlling their local voice channels by a SS7 Signaling Stack Configure message received from the SS7 card.

With this information, CSP Call Control can communicate with the stack controlling the voice channels, and the SS7 stacks can communicate with any remote CSP Call Control components, based on the fact that every node knows the global span assignments, which determine local and remote connections. To make connections in the CSP ring, all nodes must have information about the spans on all other nodes. Since each span is given a unique ID, and all call connections occur via the combined information of channel and span IDs, global span assignment information is essential to every node. See the Connect (0x00) message in the API Reference.

See Signaling System Number Seven.
See Common Channel Signaling.
Positive acknowledgment to a message
A number that addresses a node in a SS7 network.
Range of channels provided by T1 or E1 transmission service. A physical span is a group of channels taking up a single physical wire. A logical span is a group of channels taking up less than a single logical wire, or carried over more than one physical wire.
A digital communications link - voice, data, and video at a 2.048 Mbps rate; 30B/2D or 31B/1D (ISDN); non-North American version of T1.
Digital communications link - voice, data, and video at a 1.544 Mbps rate (24 64 Kbps channels)
Link that connects to the same node
Destination Point Code
CICs. Identify the voice circuits controlled by SS7 Signaling Links.
See Circuit Identification Codes.
The condition of a component at a given instant. The current "context" of a PPL object, such as Idle, Seizing, Answered. In PPL files, a State is represented by a circle.
Setting up, monitoring, and tearing down calls.