Configuring Trunk Group Settings

The Trunk Group Settings table lets you configure various settings per Trunk Group ID, which is assigned to a Trunk Group in Configuring Trunk Groups. The main configuration includes the following:

■ Channel select method, which defines how the device allocates incoming IP-to-Tel calls to the channels of a Trunk Group.
■ Registration method for registering Trunk Groups to remote IP servers (Serving IP Group).

The Trunk Group Settings table also provides an Action drop-down button with commands that let you perform various actions per configured Trunk Group:

■ Lock / Unlock: Locks (blocks) a Trunk Group in order to take its member trunks out-of-service. For more information, see Locking and Unlocking Trunk Groups.
■ Register / Un-Register: Initiates a registration request for the Trunk Group with a Serving IP Group. For more information, see the description of the 'Registration Mode' parameter of the Trunk Group Settings table in this section.

The following procedure describes how to configure settings for Trunk Groups through the Web interface. You can also configure it through ini file [TrunkGroupSettings] or CLI (configure voip > gateway trunk-group-setting).

➢ To configure Trunk Group settings per Trunk Group ID:
1. Open the Trunk Group Settings table (Setup menu > Signaling & Media tab > Gateway folder > Trunks & Groups > Trunk Group Settings).
2. Click New; the following dialog box appears:

3. Configure settings for a Trunk Group ID according to the parameters described in the table below.
4. Click Apply.

Trunk Group Settings Table Parameter Descriptions

Parameter

Description
General

'Index'

[Index]

Defines an index number for the new table row. Up to 101 rows can be configured.

Note: Each row must be configured with a unique index.

'Name'

trunk-group-name

[TrunkGroupName]

Defines a descriptive name, which is used when associating the row in other tables.

The valid value can be a string of up to 40 characters. By default, no name is configured.

if you enable the [UseSIPtgrp] or [UseBroadsoftDTG] parameters, the name also represents the Trunk Group in the SIP 'tgrp' parameter in outgoing INVITE messages (according to RFC 4904) and/or REGISTER messages (depending on the [UseSIPtgrp] parameter settings). For example, if you configure the parameter to "ITSP-ABC":

sip:+16305550100;tgrp=ITSP-ABC;trunk-context=+1-630@isp.example.net;user=phone

If you don't configure the 'Name' parameter, the Trunk Group number is set as the value in the 'tgrp' parameter, for example:

sip:+16305550100;tgrp=TG-1;trunk-context=+1-630@isp.example.net;user=phone

Note: Configure each row with a unique name.

'Trunk Group ID'

trunk-group-id

[TrunkGroupId]

Defines the Trunk Group by its ID number, which you configured in Configuring Trunk Groups.

'Channel Select Mode'

channel-select-mode

[ChannelSelectMode]

Defines the method by which IP-to-Tel calls are assigned to the channels of the Trunk Group.

■ [0] By Dest Phone Number = The channel is selected according to the called (destination) number. If the number is not located, the call is released. If the channel is unavailable (e.g., busy), the call is put on call waiting (if call waiting is enabled and no other call is on call waiting); otherwise, the call is released.
■ [1] Channel Cyclic Ascending = The next available channel in the Trunk Group, in ascending cyclic order is selected. After the device reaches the highest channel number in the Trunk Group, it selects the lowest channel number in the Trunk Group, and then starts ascending again.
■ [2] Always Ascending = The lowest available channel in the Trunk Group is selected, and if unavailable, the next higher channel is selected.
■ [3] Cyclic Descending = The next available channel in descending cyclic order is selected. The next lower channel number in the Trunk Group is always selected. When the device reaches the lowest channel number in the Trunk Group, it selects the highest channel number in the Trunk Group, and then starts descending again.
■ [4] Always Descending = The highest available channel in the Trunk Group is selected, and if unavailable, the next lower channel is selected.
■ [5] Dest Number & Cyclic Ascending = The channel is selected according to the called number. If the called number isn't found, the next available channel in ascending cyclic order is selected.

Note: If the called number is located, but the port associated with the number is busy, the call is released.

■ [6] By Source Phone Number = The channel is selected according to the calling number.
■ [7] Trunk Cyclic Ascending = The channel from the first channel of the next trunk (adjacent to the trunk from which the previous channel was selected) is selected.

■ [8] Trunk & Channel Cyclic Ascending = The device implements the Trunk Cyclic Ascending and Cyclic Ascending methods to select the channel. This method selects the next physical trunk in the Trunk Group, and then selects the B-channel of this trunk according to the Cyclic Ascending method (i.e., selects the channel after the last allocated channel).

For example, if the Trunk Group includes two physical trunks, 0 and 1:

✔ For the first incoming call, the first channel of Trunk 0 is selected.
✔ For the second incoming call, the first channel of Trunk 1 is selected.
✔ For the third incoming call, the second channel of Trunk 0 is selected.

■ [11] By Dest Number & Ascending = The device allocates channels to incoming IP-to-Tel calls as follows:
a. The device attempts to route the call to the channel that is associated with the destination (called) number. If located, the call is sent to that channel.
b. If the number is not located or the channel is unavailable (e.g., busy), the device searches in ascending order for the next available channel in the Trunk Group. If located, the call is sent to that channel.
c. If all channels are unavailable, the call is released.

Note: If the parameter is not configured, the Trunk Group's channel select method is according to the global parameter [ChannelSelectMode].

'Registration Mode'

registration-mode

[RegistrationMode]

Defines the registration method of the Trunk Group.

■ [0] Per Endpoint = Each channel in the Trunk Group registers individually. The registrations are sent to the 'Serving IP Group ID' if configured in the table; otherwise, it is sent to the default Proxy, and if no default Proxy, then to the Registrar IP.
■ [1] Per Gateway = (Default) Single registration for the entire device. This is applicable only if a default Proxy or Registrar IP is configured and Registration is enabled (i.e., parameter [IsRegisterUsed] is set to 1). In this mode, the SIP URI user part in the From, To, and Contact headers is set to the value of the global registration parameter, [GWRegistrationName] or username if [GWRegistrationName] is not configured.
■ [4] Don't Register = No registrations are sent by endpoints pertaining to the Trunk Group. For example, if the device is configured globally to register all its endpoints (using the parameter [ChannelSelectMode]), you can exclude some endpoints from being registered by assigning them to a Trunk Group and configuring the Trunk Group registration mode to Don't Register.
■ [5] Per Account = Registrations are sent (or not) to an IP Group according to the settings in the Accounts table (see Configuring Registration Accounts).

An example is shown below of a REGISTER message for registering endpoint "101" using the registration Per Endpoint mode:

REGISTER sip:SipGroupName SIP/2.0
Via: SIP/2.0/UDP 10.33.37.78;branch=z9hG4bKac862428454
From: <sip:101@GatewayName>;tag=1c862422082
To: <sip:101@GatewayName>
Call-ID: 9907977062512000232825@10.33.37.78
CSeq: 3 REGISTER
Contact: <sip:101@10.33.37.78>;expires=3600
Expires: 3600
User-Agent: Sip-Gateway/7.40A.600.203
Content-Length: 0

The "SipGroupName" in the Request-URI is configured in the IP Groups table (see Configuring IP Groups).

Note:

■ If the parameter is not configured, registration is done according to the global registration parameter [ChannelSelectMode].
■ To enable Trunk Group registration, configure the global parameter [IsRegisterNeeded] to 1. This is unnecessary for Per Account registration mode.
■ If the device is configured globally to register Per Endpoint and an channel group includes four channels to register Per Gateway, the device registers all channels except the first four channels. The group of these four channels sends a single registration request.
■ When configured to Per Account, you can configure (using the [RegisterByTrunkGroupStatus] parameter) if the device sends a registration request to the Serving Trunk Group (SIP registrar), based on the Trunk Group's status (in-service or out-of-service) for ISDN PRI and CAS.

'Used By Routing Server'

used-by-routing-server

[UsedByRoutingServer]

Enables the use of the Trunk Group by a third-party routing server or ARM for routing decisions.

■ [0] Not Used (default)
■ [1] Used

For more information, see Centralized Third-Party Routing Server.

SIP Configuration

'Gateway Name'

gateway-name

[GatewayName]

Defines the host name of the SIP From header in INVITE messages, and the From and To headers in REGISTER requests.

By default, no value is defined.

Note: If the parameter is not configured, the global parameter [SIPGatewayName] is used.

'Contact User'

contact-user

[ContactUser]

Defines the user part for the SIP Contact URI in INVITE messages, and the From, To, and Contact headers in REGISTER requests.

The valid value is a string of up to 60 characters. By default, no value is defined.

Note:

■ The parameter is applicable only if the 'Registration Mode' parameter is configured to Per Account and registration based on the Accounts table is successful.
■ If registration fails, the user part in the INVITE Contact header is set to the source party number.
■ The 'Contact User' parameter in the Accounts table overrides this parameter (see Configuring Registration Accounts).

'Serving IP Group'

serving-ip-group

[ServingIPGroupName]

Assigns an IP Group to where the device sends INVITE messages for calls received from the Trunk Group. The actual destination to where the INVITE messages are sent is according to the Proxy Set associated with the IP Group. The Request-URI host name in the INVITE and REGISTER messages (except for Per Account registration mode) is set to the value of the 'SIP Group Name' parameter configured in the IP Groups table (see Configuring IP Groups).

Note:

■ If the parameter is not configured, the INVITE messages are sent to the default Proxy or according to the Tel-to-IP Routing table (see Configuring Tel-to-IP Routing Rules).
■ If the PreferRouteTable parameter is set to 1 (see Configuring Proxy and Registration Parameters), the routing rules in the Tel-to-IP Routing table take precedence over the selected Serving IP Group ID.

'MWI Interrogation Type'

mwi-interrogation-type

[MWIInterrogationType]

Defines message waiting indication (MWI) QSIG-to-IP interworking for interrogating MWI supplementary services.

■ [255] Not configured.
■ [0] None = Disables the feature.
■ [1] Use Activate Only = MWI Interrogation messages are not sent and only "passively" responds to MWI Activate requests from the PBX.
■ [2] Result Not Used = MWI Interrogation messages are sent, but the result is not used. Instead, the device waits for MWI Activate requests from the PBX.
■ [3] Use Result = MWI Interrogation messages are sent, its results are used, and the MWI Activate requests are used. MWI Activate requests are interworked to SIP NOTIFY MWI messages. The SIP NOTIFY messages are sent to the IP Group defined by the NotificationIPGroupID parameter.

Note:

■ The parameter is applicable only to digital interfaces.
■ The parameter appears in the table only if the VoiceMailInterface parameter is set to 3 (QSIG) (see Configuring Voice Mail).

Status

'Admin State'

[AdminState]

(Read-only) Displays the administrators state:

■ "Locked": The Lock command has been chosen from the Action drop-down button.
■ "Unlocked": The Unlock command has been chosen from the Action drop-down button.

'Status'

(Read-only) Displays the current status of the trunks/channels in the Trunk Group:

■ "In Service": Indicates that all channels in the Trunk Group are in service, for example, when the Trunk Group is unlocked or Busy Out state cleared (see the [EnableBusyOut] parameter for more information).
■ "Going Out Of Service": Appears as soon as you choose the Lock command and indicates that the device is starting to lock the Trunk Group and take channels out of service.
■ "Going Out Of Service (<duration remaining of graceful period> sec / <number of calls still active> calls)": Appears when the device is locking the Trunk Group and indicates the number of buys channels and the time remaining until the graceful period ends, after which the device locks the channels regardless of whether the call has ended or not.
■ "Out Of Service": All fully configured trunks in the Trunk Group are out of service, for example, when the Trunk Group is locked or in Busy Out state (see the [EnableBusyOut] parameter).