Dialogic IMG - How to configure SS7 F Links on a Dialogic Integrated Media Gateway (IMG)
Prerequisites
The reader should be familiar with the structure of SS7 networks, SS7 protocols and SS7 terminology.
This article also assumes that the reader is familiar with configuration of the Dialogic IMG Integrated Media Gateway (IMG).
Before configuring the SS7 links, the TDM links (T1 or E1) that will carry the SS7 links must be configured.
Procedure
The IMG functions as an SSP and supports both A and F links.
This procedure describes the steps required to configure an SS7 F link on the IMG.
The following information will be needed prior to starting the configuration:
The SS7 Point Codes (OPC and DPC)
The T1 or E1 span that the SS7 link(s) will be on, and the timeslot the link is on.
The ISUP variant that will be used (ANSI, ITU, ETSI, other)
The Network Indicator
• 0 - International Network
• 1 - Spare (for international Network)
• 2 - National Network
• 3 - Spare (for National Network)
Before being able to configure the SS7 stack, you will need to configure the T1 or E1 spans that will be used for the SS7 links.
1. Configure the SS7 Stack. Select the ISUP variant, enter the OPC, and verify the remaining parameters (Cause Location, Exchange Type, Network Indicator, etc.)
2. Configure the SS7 linkset.
• ClientView will automatically populate the Links Set ID with the next available ID
• Enter the APC. For F-Links this is the same as the DPC.
3. Configure the SS7 Route to the DPC.
• Set the route type to "New"
• Enter the DPC
4. Configure the SS7 Link(s). TDM (T1/E1) spans must be configured prior to this step.
• Select the Interface - Offset. (T1 or E1) span.
• Select the channel (DS0) that the link is on
• Select the Signaling Link Code (SLC)
• Select the Data Rate.
Glossary of Acronyms / Terms
Service Switching Points (SSPs)
• SSPs are PSTN switches that originate or terminate calls, or route calls to other switches (tandem switches)
• SSPs exchange SS7 messages to set up, manage and release voice circuits
Service Control Points (SCPs)
• SCPs are database servers that respond to requests from SSPs for call routing information
Signal Transfer Points (STPs)
• STPs are packet switches that serve as routers in the SS7 network
• Incoming SS7 messages are switched to outgoing links based on routing information contained in the messages (not just based on the destination numbers)
A Link:
• An A (Access) link connects a signaling end point (e.g., an SCP or SSP) to an STP.
F Link:
• An F (fully associated) link connects two signaling end points (SSPs).
OPC - Originating Point Code
DPC - Destination Point Code
APC - Adjacent Point Code