Signaling Variant

After creating the Signaling Variants object, up to ten individual signaling variants can be created. This is accomplished using the Signaling Variant object. Within the Signaling Variant object a base variant can be created. This base variant will then be modified to create a custom variant through the Variant Entry object created under it. To create the Signaling Variant object, right click on the Signaling Variants object and select New Signaling Variant. The 2020 IMG supports creating variants for SS7 and SIP-T. Below is short description of each of the variants supported.

Note: Creating and modifying signaling variants is very difficult to do. Before creating or modifying a custom signaling variant, contact Dialogic Technical Support. Dialogic Technical Support have created and customized many variants and in most cases would be able to assist customers in creating the custom variant using an existing variant file that has already been previously created/modified.

 

Description:

The Signaling Variant Pane allows user to create a signaling variant for either SS7, CAS, or SIP-T. When creating this pane select from drop down menu in the Variant Type field which protocol will be used to create the variant. Below is short description of each of the variants supported.

 

SS7 - Variants are based on one of the base ISUP variants. SS7 Signaling variants are used to modify the base variants based on country-specific or regulatory needs. From the SS7 Variant object, a variant can be imported. Dialogic has many variants already created and ready to be imported. Contact Dialogic Support for more information.

CAS - Variants are used to modify base variant (CCITT for E1, Trunk Type specific defaults for T1) based on country-specific or regulatory requirements.

SIP-T - This pane can be modified to use a base variant name to be used by the IMG in outgoing ISUP MIME messages for SIP-T.

 

Note: Once a custom variant is assigned to a stack you cannot modify or delete an existing entry in the variant. You can however add new entries.

 

Accessing this Pane:

Dialogic IMG EMS -> New Signaling Variants -> Signaling Variant

sc_tree_signaling_variant.png

 

Maximum Objects:

10 per EMS (variants must have unique ID and variant name)

 

Related Topics:

Variant Entry

Creating Custom SS7 Variants

Configuring SIP-T

 

Click on the Technical Notes link for technical information on the Signaling Variant for SS7 object.

 

ClientView Pane (T1 CAS Pane):

sc_signalingvariant_t1cas.png

 

ClientView Pane (E1 CAS Pane):

sc_sigvar_e1cas.png

 

 

Field Descriptions (E1/T1 CAS): (SS7 and SIP-T described below)

Variant Name:

In this field enter a name that identifies this particular variant. Click in the Variant Name field and enter the name. The name can be up to 25 characters.

 

Variant Type:

Select CAS from drop down menu from the Variant Type field. CAS will be the protocol used in this variant.

CAS - Channel Associated Signaling variant will be created

 

Base Variant:

Select from drop down menu the base variant. The base Variant differs depending on the Variant Type. See tables below which displays the selections for each of the Variant Types. This field specifies the protocol that the new variant will be based on.

T1 Signaling - The Variant being created will use T1 Protocol for signaling

E1 Signaling - The Variant being created will use E1 Protocol for signaling

 

Variant Id:

The Variant ID field is automatically populated with the next variant ID in the list. To change the default Variant ID, select a different ID from drop down menu. ID's range from 1-10

 

Trunk Type (T1 CAS Only):

If the Variant Type is CAS, the selections from drop down menu will be:

E+M - Used in T1 Signaling. E+M is used in CAS for signaling and supervisory roles. E+M uses two lines (E line and M line) to communicate typically between two PBX's or between a Router and a PBX because of its supervisory role. If the network uses E+M signaling select E+M from drop down menu.

FXS loop-start - FXS loop-start is the simplest form of CAS signaling. This form of signaling uses Off Hook current draw to signal the CO to  provide Dial Tone. The disadvantage to FXS loop-start is there no way of being notified that the far end has answered or disconnected. FXS loop-start is typically used on POTS lines and is typically used as signaling between a POTS phone and the PBX. If the network uses loop-start signaling select FXS loop-start from drop down menu.

 

In Start Dial / Out Start Dial (T1 CAS Only):

Below is a table which shows the signaling selections under the In Start Dial and Out Start Dial fields.

 

SETTING IN CLIENTVIEW

In Start Dial

Out Start Dial

SIGNALING TYPE

WINK

WINK

SIGNALING TYPE

IMMEDIATE

FIXED PAUSE

SIGNALING TYPE

DIAL TONE

DIAL TONE

SIGNALING TYPE

NONE

NONE

 

 

Wink - Wink is the most commonly used protocol. When a phone goes off hook the originating switch signals to the next switch/router that it is going off hook. The second switch/router in turn sends a wink back to the original switch. Wink is typically used in E+M signaling. If wink is configured as the signaling type in the In Start Dial field then wink should be configured on the Out Start Dial field as well.

Immediate - No Winks are sent. This is the most basic protocol. The originating switch/router goes off-hook. The switch/router then  waits for a finite period of time (typically around 100-200 ms). At the end of this finite time, the switch then sends the dialed digits to the far end. There is no winking or supervisory roles being played. If Immediate is used in the In Start Dial then Fixed Paused should be used in the Out Start Dial.

Dial Tone - With Dial Tone Signaling once a channel is seized and Dial Tone is generated then the dtmf digits are sent. This signaling is used in FXS loopstart. If the In Start Dial is set to Dial Tone then the Outstart Dial will be set at None. If the Out Start Dial is set at None then the In start dial would be set at Dial Tone.

 

CAS Idle Bits (E1 CAS Only):

In E1 CAS bits a-d are set at either a 1 or a 0 depending on whether the channel is in Idle/Released State or in a Seized state. The default is A bit and D bit which is 0x09. These can be changed by clicking in the CAS idle bit field. A Select Multiple Items box will appear. By using <Ctrl> + Mouse click you can select/deselectwhich bits to be used for idle. Below is table with the standard default states for ITU-T Q.421

 

State of Timeslot 16 in ITU-T Q.421

State of the Circuit

Signaling Code

 

Forward

Backward

 

A

B

C

D

 

A

B

C

D

Idle/Rel

1

0

0

1

 

1

0

0

1

Seized

0

0

0

1

 

1

0

0

1

Seized Acknowledged

0

0

0

1

 

1

1

0

1

Answered

0

0

0

1

 

0

1

0

1

Clear-Back

0

0

0

1

 

1

1

0

1

Clear-Forward

1

0

0

1

 

0/1

1

0

1

Blocked

1

0

0

1

 

1

1

0

1

 

*On Hook = 1

*Off Hook = 0

 

Note: In ITU-T Q.421 Bits C and D are fixed at C=0 D=1

 

CAS out Of Service Bits (E1 CAS Only):

In E1 CAS the default bits used in ITU-T Q.421 are Bit A, Bit B, and Bit D. This default can be changed by clicking in the CAS Out of Service Bits field. A Select Multiple Items box will appear. By using <Ctrl> + Mouse click you can select/deselect which bits to be used.

 

Address Signaling Type (CAS Only):

MFR1 (Default for T1) - Multi Frequency Inband Signaling Technique typically used in on T1 lines in North America. MFR1 is used for trunk signaling between Switches/Routers.

DTMF (for E1 also requires PPL Configuration) - Dual Tone Multi Frequency Signaling Technique used over the line in the voice-frequency band from the telephone to the call switching center.

MFR2 (Default for E1) - Multi Frequency Inband Signaling Technique typically used between exchanges.

 

Outbound Multi-string (T1 CAS Only):

Disabled (default)

Stage1 (ANI+DN)

Stage1 (DN+ANI)

Stage2 (ANI+DN)

Stage2 (DN+ANI)

 

Busy Out Flag (CAS Only):

The Busy Out feature is disabled by default. Busy Out is often used during maintenance periods. Only channels configured with a trunk type of E&M can use Busy Out feature. Busy Out is configured in the CAS Circuits pane. You cannot "busy out" a channel if this flag is disabled.

Busy Out Disabled (Default) - The Busy Out Feature is disabled

Busy Out Enabled - Send a busy signal to the inbound caller

 

Click on the Technical Notes link for technical information on the Busy Out feature.

 

 

 

Field Descriptions (E1/T1 SS7)

ClientView Pane (SS7):

sc_signaling_variants_ss7.png

 

Variant Name:

In this field enter a name that identifies this particular variant. Click in the Variant Name field and enter the name. The name can be up to 25 characters.

 

Variant Type:

Select CAS from drop down menu from the 'Variant Type' field. CAS will be the protocol used in this variant.

SS7 - SS7 Signaling variant will be created

 

Base Variant:

Select from drop down menu the base variant. The base Variant differs depending on the Variant Type. See tables below which displays the selections for each of the Variant Types. This field specifies the protocol that the new variant will be based on.

 

Variant Type SS7

ANSI 97

ANSI 95

ANSI 92

ITU 97

ITU 93

CCITT 88

ETSI V1

ETSI V2

ETSI V3

China

JTISUP

 

Variant Id:

The Variant ID field is automatically populated with the next variant ID in the list. To change the default Variant ID, select a different ID from drop down menu. ID's range from 1-10

 

 

 

Field Descriptions (SIP-T):

ClientView Pane (SIP-T):

sc_signalingvariant_sipt.png

 

Variant Name:

In this field enter a name that identifies this particular variant. Click in the Variant Name field and enter the name. The name can be up to 25 characters.

 

Variant Type:

Select CAS from drop down menu from the 'Variant Type' field. CAS will be the protocol used in this variant.

SIP-T - SIP-T Signaling variant will be created

 

Base Variant:

Select from drop down menu the base variant. The base Variant differs depending on the Variant Type. See tables below which displays the selections for each of the Variant Types. This field specifies the protocol that the new variant will be based on.

 

Variant Type SIP-T

ANSI 97

ANSI 95

ANSI 92

ITU 97

ITU 93

CCITT 88

ETSI V1

ETSI V2

ETSI V3

China

JTISUP

 

Variant Id:

The Variant ID field is automatically populated with the next variant ID in the list. To change the default Variant ID, select a different ID from drop down menu. ID's range from 1-10

 

 

Object Table Tab:

This table shows a list of the configured Variant entries.