The SS7 Stack object is created under the SS7 Network Object. The SS7 stack object is created by right clicking on the SS7 Network object and selecting New SS7 Stack. The SS7 stack created will need to be configured. Refer to the topic below for information on how to configure each individual field. Once the stack is created and configured, the Destination, Link Set, and Route objects are created under it. Refer to the information below.

Web GUI Page

Dialogic > SS7 > SS7 Network > New SS7 Stack

Maximum Objects

Four SS7 Stacks can be configured per SS7 Network object. Since four SS7 Network objects can be created per Web GUI application, then up to sixteen stacks can be created per SS7 Signaling object

Related Topics and Dependencies

When creating an SS7 network which includes stacks, links, link sets, routes, destinations, etc, the dependencies are too numerous to explain in this document. Please refer to the Configure SS7 topic for information on how to configure an SS7 network.

SS7 - Network

M3UA SS7 Destination

SS7 - Link Set

Field Descriptions

Stack ID

This Stack ID field automatically populates the SS7 stack being configured with the next available ID. Within each SS7 Network, the ID's range from 0-3. This lets the user configure stacks with ID's 0-3 within SS7 Network ID:0, stacks with ID's 0-3 within SS7 Network ID:1 and so on to a maximum of 16 total stacks. To modify the Stack ID, click in the Stack ID field and select a different Stack ID from the drop down menu.

SS7 Variant

The IMG 2020 supports creating custom SS7 variants through the use of the Programmable Protocol Language (PPL) or by importing any custom designed variants. Any custom SS7 variants that either gets created using the Variants object or imported through the Variant Entry object will be displayed in the drop down menu of the SS7 Variant field. When a custom SS7 Variant is created it is created from a Base Variant such as ANSI 97, ITU97, ETSI V1, etc. When populating the SS7 Variant field with a custom SS7 Variant, the field just below labeled ISUP will automatically get populated with the base variant from the custom variant created. Refer to the IMG 1010 - Signaling Variant or Importing / Exporting Variants topics for more information on creating and importing custom variants.

Once a custom variant is assigned to an SS7 stack, the custom variant entries cannot be modified or deleted. The SS7 variant must be de-selected from the SS7 stack or the stack may need to be deleted before any entries can be modified. 

ISUP

If Base Only (Default) is selected in the SS7 Variant field above, the ISUP field will have a drop down menu displaying all the supported SS7 Variants. Select the variant needed from drop down menu. The table below displays the variants that are displayed in the drop down menu along with their point code format. If a custom variant is created, this field will default to the ISUP variant configured in the custom variant.

OPC (Originating Point Code)

MTP Layer 3 provides the message routing and failure handling capabilities for the message transport. Each SS7 stack is identified within a network using an SS7 Point Code. This field specifies the originating point code value of the SS7 stack. Point codes are expressed in dotted decimal format. See Point Code Format in table above. To enter a point code, click in the first window of the OPC field and enter the first value. To move to the next two fields, hit the <TAB> key and enter the second and third value. The IMG 2020 Web GUI has error checking and if the Point Code being entered does not satisfy the point code format of the variant then the box where the incorrect point code was entered will appear with a red shading around it and an error indicating the maximum value for the field is xxx will appear. The Red shading indicates the value entered is out of bounds. See screen capture below.

MTP Pause

When the IMG 2020 receives a TFP (Transfer Prohibit) message from an endpoint indicating that a Destination Point Code is not allowing traffic to pass, the MTP3 layer sends the MTP Pause primitive to the SS7 Stack informing the stack that the Destination cannot accept any traffic. At this point the IMG 2020 will no longer send any messages to that destination point code (DPC). Once the destination is available the endpoint sends a TFA (Transfer Allowed) message indicating that it is available. At this point, an MTP Resume primitive is sent to the SS7 stack. What the IMG 2020 does with this information is configured in this field.

Immediate (Default) - If the IMG 2020 stack receives an MTP-Pause primitive the IMG 2020 will immediately process the primitive and take all CICs going to that destination Out of Service immediately.

Delayed - The IMG 2020 stack receives the MTP-Pause primitive but the processing of the message will be delayed. The amount of time the processing of the MTP-Pause primitive will be delayed is set in the SS7 Variant Entry object. Within the SS7 Variant Entry Object there is a field labeled PPL Component Id. Select ISUP SPRC in the PPL Component Id field and select PPL Timers in the PPL Entity type field. At this point the PPL Timer Value can be set. See Signaling Variant Element.

Cause Location

The REL message indicates that a circuit is being released. This message can be sent in either direction and contains a mandatory Cause Indicator Parameter that indicates why a circuit was released. Within the Cause Indicator is the location field. The location field describes what part of the network was the reason the REL message was issued. The Cause Location field in the SS7 Stack object has a drop down menu containing the values below. The value selected will be populated in the location field of the Cause Indicator Parameter when a call is released.

User (default) - Message Generated by User

Local private network - Message generated by private network serving the local user

Local public network - Message generated by public network serving the local user

Transit network - Message generated by transit network

Remote public network - Message generated by public network serving the remote user

Remote private network - Message generated by private network serving the remote user

Local Interface - Message Generated by local user

International network - Message generated by international network

Network Beyond Interworking Point - Message generated by network beyond inter-working point.

Under the ISUP Group object there is an object labeled Location Override where the above values can be overridden. For more information, refer to the SS7 - Destination - ISUP Group - Location Override link

Exchange Type

Type B (Default) - The IMG 2020 sends a GRS/RSC at start-up. The IMG 2020 waits for a remote GRA/RLC before bringing the CICs in service.

Type A - The IMG 2020 does not send any messages at start-up, but responds to a GRS with a GRA, or an RSC with an RLC. 

Network Indicator

The network indicator is part of the ISUP Service Information Octet (SIO). In MTP (Level 3) the network indicator specifies the type of message (National/International) and is often used for routing to a national or international network. The spare values are often used for testing and for temporary use during Point Code conversions.

National (Default) - Used for ANSI ISUP Variants.

International - Used for non-ANSI ISUP Variants.

01 - Spare - Often used for testing and for temporary use during Point Code conversions

03 - Spare - Often used for testing and for temporary use during Point Code conversions  

Suppress UCIC's

When a message is received with a CIC that is not defined at the receiving node, an Unequipped Circuit Code (UCIC) message is sent in response. The message field contains the unidentified code. The Suppress UCIC's (Unequipped Circuit Identification Code) field controls the transmitting of UCIC's. By default, the Suppress UCIC's field is disabled. This field has a drop down menu allowing field to be modified.

Disabled (Default) - Allow UCIC messaging to be sent when CIC receiving the messaging is Unequipped or not provisioned for use.

Enabled -  Do not allow UCIC messaging to be sent when CIC receiving the messaging is Unequipped or not provisioned for use. 

CFN Status

The CFN or Confusion Message is sent in response to any message (other than a confusion message) to indicate that all or part of a received message was unrecognized. The receiving entity does not know how to handle the received message so it transmits the CFN message instead.

Enabled (default) - If IMG 2020 receives a message that is not recognized, IMG 2020 will respond and transmit a CFN (Confusion Message) back to the originator.

Disabled - If IMG 2020 receives a message that is not recognized, IMG 2020 will not respond with a CFN (Confusion Message).

This only applies to ISUP messages.

Japanese MTP Variant

The Japanese MTP Variant will default to "Not Used" as long as the ISUP field above is displaying anything other than JTISUP. When configuring Japan ISUP (JTISUP), this field selects the appropriate configuration for MTP. The default Japanese MTP Variant is TTC. See below.

JT - Supports Japan Telecom

TTC - Supports Nippon Telecom and Telephone of Japan 

Additional JT-ISUP Information

The IMG 2020 supports JT-ISUP, the SS7 standard for Japan (JT-Q.763). Select this variant in the ISUP field of the SS7 Stack pane. If JT-ISUP is selected, an MTP variant in the Japanese MTP Variant field must also be chosen.

Differences from other ISUP version

• Point code format is 7-4-5* Manual COT test not supported* Unique CIC mapping scheme (see )Troubleshooting

• Check for Point Code Mismatch* Make sure Distant End Gateway supports JT-ISUP 

A/B Plane Bit Insertion and Validation

Used when configuring JTISUP

Disabled (Default)

Enabled

SCCP

SCCP is the transport layer and routing mechanism for TCAP messages. Enable SCCP on the SS7 stack if TCAP messaging is to be used. Select from drop down menu one of the following selections.

Disabled (Default) - SCCP Protocol is disabled in the SS7 stack.

ANSI - Enable SCCP Protocol for use with ANSI standards

ITU - Enable SCCP Protocol for use with ITU standards

TCAP

Transaction Capabilities Application Part (TCAP), a protocol in the SS7 protocol suite, enables the deployment of advanced intelligent network services by supporting non-circuit related information exchange between signaling points using the Signalling Connection Control Part (SCCP) connection less service. TCAP also supports remote control - ability to invoke features in another remote network switch. TCAP is used on the IMG 2020 for services such as Message Waiting Indicator and TCAP CNAM Database Queries.

Disabled (Default) - TCAP Protocol is disabled in the SS7 stack.

ANSI - Enable TCAP Protocol for use with ANSI standards

ITU - Enable TCAP Protocol for use with ITU standards

M3UA Service Mode

Disabled (Default) - M3UA signaling is disabled. Stacks configured with this field disabled cannot be used in M3UA configuration

Signaling Gateway (SG) Mode - The stack being created will have M3UA Service set to Signaling Gateway mode. Signaling Gateway mode can be configured on up to (4) stacks per SS7 Network object. Refer to the Sigtran / M3UA topic for more information. When the Signaling Gateway Mode is selected, either SCCP, TCAP, or both will need to be configured from the SCCP and TCAP fields explained above.

Application Server (AS) Mode - The stack being created will have M3UA Service set to Application Server mode. Application Server mode can be configured on up to (4) stacks per SS7 Network object. Refer top the Sigtran/M3UA topic. When the Application Server Mode is selected, either SCCP, TCAP, or both will need to be configured from the SCCP and TCAP fields explained above.

IPSP Server (IPSP) Mode - The stack being created will have M3UA Service set to IP Server Process mode. IPSP mode can be configured on up to (4) stacks per SS7 Network object. When the IP Server Process Mode is selected, either SCCP, TCAP, or both will need to be configured from the SCCP and TCAP fields explained above.

Up to (4) stacks can be created per IMG 2020 using the M3UA protocol. There is no limitation to how many of each type of stack that can be created. For example, on one physical IMG 2020 node, four stacks can be created. The stacks could be all Signaling Gateway Mode stacks, all Application Server Mode stacks, or a mix of both.

Message Compatibility Pass On

This parameter provides instructions to an exchange processing an ISUP message that the message is unrecognized and it does not understand the message. See selections below.

On (Default) - When receiving an incompatible or unrecognized ISUP message, pass it on the outgoing leg.

Off - When receiving an incompatible or unrecognized ISUP message, DO NOT pass it on to the outgoing leg.

This sets the Message Compatibility Pass On parameter in the SS7 stack. This parameter can be configured for each ISUP group also. See IMG 1010 - ISUP Group - ANSI or IMG 1010 - ISUP Group - ITU / ETSI link.