Creating and Modifying ISDN Signaling Groups

Fractional

TEI Assignment

TEI

The administrative state of the link:

• Enable: Enables the signaling group.
• Disable: Disables the signaling group.
• Drain: When Drain is selected, calls that are currently up remain connected. However, new calls and forking are not allowed for the Signaling Group. This allows all the calls to be drained from the SG.

Specifies the ISDN user/network side for this signaling group .

Specifies when to generate local ring back:

• Auto on Alert. Generates Ringback on Alert message. Depends if inband audio is available.
  
• Auto On Alert/Progress  Generates Ringback on Alert/Progress message. Depends if inband audio is available.
• Always on Alert. Always generates inband ringback on Alert message.
  
• Always on Alert/Progress: Always generates inband ringback on Alert/Progress message.
• Never: Never generate inband ringback.

Specifies if received overlap dialing is enabled on the signaling group. Valid only for Euro ISDN (ETSI) and QSIG Switch Variants.

Note: To route Calls faster: If you are not using Overlap dialing, you can turn off Overlap Receive Mode to remove any time the SBC waits before routing the call, or lower the T302 timer to route the call faster.

Specifies whether or not a Q.931 PROGRESS message is sent to the far-end so that it does not timeout (T310) while the SIP response is pending from the SIP leg, causing the call to release.

This setting should be enabled when deploying the SBC 1000-2000 and Skype with a PSTN Provider. Only disable this parameter if your PSTN environment does not support PROGRESS sent before ALERT.

Specifies the TEI to assign for BRI when set to user side. 0 through 63 are absolute values to assign. If signaling group is PRI or network side BRI this parameter is not used. This field is available only when the TEI Assignment Type is set to Static.

 Note: The value of 0 for Static TEI is valid only for NTT. Other BRI specifications allow a value of 0 through 63 for Static TEI.

Specifies whether or not the Q.931 SETUP message is sent to the far-end should include the DISPLAY Information Element (IE).
Available only when ISDN Side is set to User and the Switch Variant is set to NI2 or Euro-ISDN.

If this option is enabled, the DISPLAY IE is populated for NI2 or Euro-ISDN switch types, otherwise the DISPLAY IE is not populated for these switch types.

In general, the DISPLAY IE is populated according to ISDN communication standards. The NI2 and Euro-ISDN specifications state that the DISPLAY IE should not be populated. This option allows you to override that configuration for your environment.

This configuration option enables the ISDN Signaling Group to add/configure a Progress IE to the outbound SETUP message if it is not present. Options are as follows:

• None (a Progress IE is not added if there is none present, and not modified if present)
• Not end to end ISDN (call is not end to end ISDN)
• Destination not ISDN (destination address is not ISDN)
• Origination not ISDN (origination address is not ISDN)
• Return to ISDN (call has returned to the ISDN)
• Interworking Encountered (interworking has been encountered)
• Inband Information (in-band information or appropriate pattern now available)
• Delay Encountered (delay in response at destination interface)

Default entry: None.

Defines how PROCEEDING/PROGRESS/ALERT messages are treated for Early Media. Valid options:

Enabled. The PI:2 (Destination not ISDN) value indicates that early media was received in PROCEEDING/PROGRESS/ALERT messages.

Disabled. The PI:2 (Destination not ISDN) value indicates that there was no early media received in PROCEEDING/PROGRESS/ALERT messages.

Note: Enabled is the default value, which indicates that PI values of 1, 2, and 8 are considered for early indicators of media; Disabled indicates that PI 2 is not considered for early media.

Send Facility Message Passthrough

Send Redirecting Number in Facility

Controls whether the redirecting number is sent in the Facility IE for EuroISDN (ETSI). This configuration also uses the following ASN.1 hard coded fields which are hidden for EuroISDN:

• ASN.1 Protocol Identifier (set as default ROSE)

• ASN.1 Numbering Space (set as default Local)

Valid entries: Enabled (sends the Redirecting number in Facility IE) or Disabled (default; does not send Redirecting number in Facility IE). This field is available only when EuroISDN is selected as the Switch Variant. All ETSI specific ISDN Signaling groups must be configured the same system-wide for this field.  

Specifies the ASN.1 numbering space for QSIG. All QSIG specific ISDN Signaling groups must be configured the same system-wide for this field.

Method that Call Control uses to allocate ISDN channels. This is only valid for Outbound or Bidirectional Direction settings.

• Standard: This option assigns the first available low numbered channel.
• Reverse Standard: This option assigns the last available high numbered channel.
• Round Robin: This option assigns channels based on next available from low numbered to high numbered.
• Least Idle: This option chooses channels based on the least idle channel.
• Most Idle: This option chooses channels based on the most idle channel.

Indicates the direction of calls supported

• Inbound: Support only incoming calls from ISDN endpoints.
• Outbound: Support only outgoing call to ISDN endpoints.
• Bidirectional: Support both incoming or outgoing calls to ISDN endpoints.

Specifies the Action Set Table to use on this signaling group. This option is only available when Inbound or Bidirectional is the value for the Direction field.

Specifies the Call Route Table to use on the signaling group to route calls with. This option is only available when Inbound or Bidirectional is the value for the Direction field.

Note: This field relates only to Inbound calls on the Signaling Group, where applied; the field applies for SBC 1000/2000 only.

In the event of a call release due to the No Channel/Circuit available release cause code, the specified cause code is sent to the relevant protocol module. For more information, refer to the list of Cause Codes.

For details refer to No Channel Available Override - Example.

Enables playing an inband message when a Progress Indicator is provided on the ISDN disconnect message. Valid entries: Yes (inband message is played post-disconnect) or No (inband message is not played).

This field supports the following example scenario: Convert DISC PI=1.8 to Progress

Maximum Message Play Time

A list of user specified Q.850 Cause Codes. If any of the specified Cause Codes appear in the DISCONNECT message, the channel is disconnected immediately. This field is only visible when the Yes is selected in the Immediate Disconnect On Causecode list box.

T301

Started when an ISDN call enters the alerting state (i.e. receive an ALERT message) and if it expires clears the call. Prevents the call from ringing forever.

T302

Specifies the time between digits in overlapped dialing.  If it expires it is assumed all digits have been received.

T303

Specifies the time after sending a ISDN SETUP message to wait for a response. First expiration will resend the SETUP and second expiration will fail the call.

T305

Specifies the time to wait after sending an ISDN DISCONNECT message to wait for the RELEASE message response. If it expires we then send an ISDN RELEASE message.

T308

Specifies the time to wait after sending an ISDN RELEASE message to wait for the RELEASE COMPLETE message response. First expiration will resend the RELEASE message and second expiration will send a RELEASE COMPLETE message.

T309

Specifies the time to wait after the D channel goes down for B channels with calls in the active state to wait for the D channel to come back up. If it expires and the D channel has not come back up the call on the B channel is cleared.

T310

Specifies the time to wait after receiving a CALL PROCEEDING message to wait for some form of call progress, i.e. a PROGRESS, ALERT or CONNECT message. If it expires the call is cleared.

T313

Specifies the time for user side ISDN to wait after sending a CONNECT message to wait for the CONNECT ACKNOWLEDGE message. If it expires then the call is cleared.

T314

Specifies the time to wait between SEGMENT messages for segmented message support in QSIG. If it expires all previously received SEGMENT messages are discarded and ignored.

T316

Specifies the time to wait after sending a RESTART message to wait for the RESTART ACKNOWLEDGE. First expiration will resend the RESTART message and second expiration will put the channel in local maintenance state for protocols that support service messaging. For protocols that don't support service messaging channel will be returned to the idle state.

T322

Specifies the time to wait after sending a STATUS ENQUIRY message to get the STATUS message response. First expiration will resent the STATUS ENQUIRY message and second expiration will clear an active call. Only started if T309 doesn't expire and the D channel comes back up before T309 expires on B channels with active calls.

T3M1(T323)

Specifies the time to wait after sending a SERVICE message to get the SERVICE ACKNOWLEDGE response. If it expires the SERVICE message will be resent. For NI-2 this is a maximum of 3 attempts before leaving the B channel in the state it was before and not changing its state.