Channel Group

The channel group object defines incoming and outgoing attributes for a group of channels. The Channel Group object allows the user to specify a set of attributes such as IP profiles, routing tables, translation tables, etc to be assigned to the specific channel group being configured. See Field Descriptions section below for a list of attributes that can be assigned to the channel group being configured.

Depending on the protocol, the IMG 2020 communicates with other entities in the network through the use of TDM DS-0's or IP Ports. A collection of TDM DS-0's or collection of IP Ports are labeled as a channel group. A channel group is created using a specific protocol such as SIP or SS7 and is used to group a collection of DS-0's or Ports to communicate with a far end entity. On the IMG 2020 the manner in which TDM DS-0's and IP Ports are allocated for channel groups is distributed differently as described below.

TDM Channel Group

A TDM channel group consists of a group of DS-0's grouped together. This is achieved by allocating a specific number of DS-1's  and DS-0's using a technique where the Starting DS1/DS0 and Ending DS-1/DS0 are configured to generate a group of DS-0's. The two TDM protocols supported are ISDN and SS7. The configuring of an ISDN channel group and SS7 channel group is very similar.

ISDN

The ISDN channel group consists of a group of B Channels that are configured under the ISDN Channel group object. These B Channels are controlled by a D-Channel under the signaling object.

SS7

The SS7 channel group consists of a group of CICs that are configured under the ISDN Channel group object. These B Channels are controlled by a D Channel under the signaling object.

VoIP Channel Group

SIP

A VoIP channel group uses a revolving pool of all available IP Ports on the IMG 2020. Within a SIP channel group, specific ports are not allocated to a specific channel group. The channel group is linked to an External SIP Gateway. The Channel group being configured would pull the IP Resources as needed. To limit the number of simultaneous calls to a SIP channel group refer to the IP Traffic Management link.

H.323

A VoIP channel group uses a revolving pool of all available IP Ports on the IMG 2020. Within a H.323 channel group, specific ports are not allocated to a specific channel group. The channel group is linked to an External SIP Gateway. The Channel group being configured would pull the IP Resources as needed. To limit the number of simultaneous calls to an H.323 channel group refer to the IP Traffic Management  link.

Web GUI Page

Dialogic > Routing Configuration > Channel Groups > New Channel Group

Maximum Objects

Up to 672 channel group objects can be created per Routing Configuration object. The channel group objects created can be any combination of SS7, ISDN, and SIP.

Related Topics and Dependencies

 Channel Groups

Channel Group Service

IP Network Element

Configure SIP (Single SIP IP)

Configure SIP (Multiple SIP IP)

Configure SS7

Configure ISDN

Field Descriptions

ID

The ID field is automatically populated with the next available ID. The ID can be changed by selecting from a range of ID's from the drop down menu. The IMG 2020 supports the following range of ID's: (0 - 671).

Name

This field defaults to ChannelGroup<x> where "x" is a numeral variable. The default name can be accepted or, an alternate name can be added by deleting the current name, clicking in the Name field, and modifying the existing name. When renaming, it is good practice to enter a name that identifies or describes this particular Channel Group.

Edit Name

Once committed, the Name field becomes read only. This field, when set to Enable, allows the user to edit the Name field.

Trunk Direction

Identifies the direction of calls on this Channel Group.

Incoming/Outgoing Trunks (Default)- Channel group will be used for both incoming and outgoing traffic. (Two way traffic)

Incoming Trunks- Channel group will be used for incoming traffic only. (One way traffic)

Outgoing Trunks- Channel group will be used for outgoing traffic only. (One way traffic)

Signaling Type

The Channel Group being created can be configured to any one of the signaling protocols displayed below. The protocol selected will dictate which fields can be modified. Any fields that cannot be modified for that particular protocol will be shaded in green and cannot be modified. The supported protocols which are in a drop down menu in this field are displayed below:

• SS7_ISUP

• ISDN

• SIP

• H323

Route Table

The Route Table field allows user to select which route table out of all route tables configured to be used for routing calls received on this channel group. Select from drop down menu the route table to be used for any calls coming in or going out of this channel group. 

Incoming IP Profile

The Incoming IP Profile field allows a user to select the IP characteristics for an incoming VoIP call. Parameters such as voice encoding, compression, payload size, and echo suppression, are configured in an IP Bearer Profile object and then selected from the drop down menu in this field. For an IP profile to appear in the drop down menu, an IP Bearer Profile must first be created. The Incoming IP Profile field applies to SIP Channel Groups only. If configuring SS7 or ISDN then this field will be shaded green.

Outgoing IP Profile

The Outgoing IP Profile field allows a user to select the IP characteristics for outgoing VoIP call. Parameters such as voice encoding compression, payload size, and echo suppression, are configured in an IP Bearer Profile object and then selected from the drop down menu in this field. For an IP profile to appear in the drop down menu, an IP Bearer Profile must first be created. The Incoming IP Profile field applies to SIP Channel Groups only. If configuring SS7 or ISDN then this field will be shaded green.

Incoming Treatment

The Incoming Treatment field lets the user decide what to do when a call comes into the IMG 2020 and fails to connect.

Release w/Cause (Default)- Release with cause is the default selection. If the call fails, the channel will release and transmit a cause code. Where the cause code is sent is dependent on the reason the call was released and whether the outgoing leg has started call setup on outgoing leg. The cause code value is dependent on the reason the call failed and eventually released.

Play Treatment- Play treatment is normally utilized for error detection or maintenance. When the Play Treatment option is selected, the IMG 2020 will play a pre-determined treatment file back to entity initiating the call. The treatment can indicate the channel is in maintenance, out of service, or use one of many reasons a treatment would want to be played on this channel.

Outgoing Treatment

Allows user to decide what to do when a call fails and is released.

Release w/Cause (Default)- Release with cause is the default selection. If the outgoing call fails, the channel will release and transmit a cause code to either the calling party, the called party or both. Where the cause code is sent is dependent on the reason the call was released and whether call setup has been initiated on outgoing leg. The cause code value is dependent on the reason the call failed and eventually released.

Play Treatment- Play treatment is normally utilized for error detection or maintenance. When the Play Treatment option is selected, the IMG 2020 will play a pre-determined treatment file back to entity initiating the call. The treatment can indicate the channel is in maintenance, out of service, or use one of many reasons a treatment would want to be played on this channel.

Incoming Translation Table

The Incoming Translation Table field identifies any Incoming translation tables that the IMG 2020 will use when performing digit translation or error detection on any incoming calls received on this Channel Group. Select from drop down menu the translation table to be used for any calls received on this Channel Group. For the translation table to appear in the drop down menu, an incoming translation table must be first be configured. Refer to the Incoming Translation Tables  topic for more information. If multiple incoming translation tables are configured then there will be multiple incoming translation tables to select from in drop down menu.

Outgoing Translation Table

The Outgoing Translation Table field identifies any outgoing translation tables that the IMG 2020 will use when performing digit translation or error detection on any outgoing calls. Select from the drop down menu, the outgoing translation table that will be used for any outgoing calls being processed through this Channel Group. For the translation table to appear in the drop down menu, an outgoing translation table must first be configured. Refer to Translation Table and Translation Element - Outgoing  for configuration information. If multiple outgoing translation tables are configured then there will be multiple translation tables to select from in drop down menu.

Hunting Options

The Hunting Options field specifies the hunting algorithm used for selecting a TDM channel to route to an outgoing call.

Alternate Odd / Alternate Even (ISDN Channel Group)- The IMG 2020 selects the outbound DS-0 based on the DS-0 number being odd or even within the DS-1. That is, the selection is based on the actual order of the DS-0 within the DS-1 rather than its order within an arbitrarily configured channel group.

Alternate Odd / Alternate Even (SS7 Channel Group)- When the channel group protocol is configured for SS7 and the Hunting Option Alternate Odd or Alternate Even is selected, the alternate odd and alternate even functionality is based on the CIC number and not the channel number.

LRU (Least Recently Used)- Selects the channel that has been used the least.

Most Idle- Selects the channel that has been idle the longest.

Round Robin Clockwise- Starts at the first channel in the channel group and routes down the list of available channels, and then repeats from the beginning of the list.

Round Robin Counter Clockwise- Same as Round Robin Clockwise, but it starts at the last channel in the channel group and routes up the channels.

Sequential Bottom Up- Starts at the last channel in the channel group and routes up. If a prior channel becomes available this channel is used before selecting the next channel from the end of the list.

Sequential Top Down- Starts at the first channel in the channel group and routes down. If a prior channel becomes available this channel is used before selecting the next channel from the end of the list.

For more information on the channel or CIC mappings refer to the CIC and Channel Mapping Options topic.

Ingress Side will Play Call Progress Tones

Select whether the IMG 2020 will play a call progress tone to an inbound call. This field is applied to the outgoing channel group only.

False (Default)- When Alerting is received on the outbound channel the IMG 2020 will not generate ring back tone to the inbound caller.

True- When field is set to True and Alerting is received on the outbound channel the IMG 2020 will generate ring back to the inbound call. Setting this field to true will also override the default mapping of the 18x alerting message (With or without SDP present). The IMG 2020 has additional rules regarding ring back when Progress indicators No. 1 and No. 8. are present. For information on this additional functionality, see Suppress Local CPT when CPG Indicators Received link.

Re-Attempt Cause Code

By default, the IMG 2020 will automatically attempt to re-route calls in response to the 34, 41, and 42 cause codes. Calls can also be rerouted on up to (4) additional cause codes. This is accomplished by clicking in the Reattempt Cause Code field. A Select Multiple Items box will appear with multiple Cause Codes to select from. More than one Cause Code can be chosen by selecting <CTRL> key and clicking on multiple entries. The IMG 2020 will automatically attempt to re-route calls in response to the selected cause codes.

Note: The IMG 2020 will not re-attempt if alerting is received prior to the release response.

Not Used (Default)- Feature Disabled. IMG 2020 will only re-route on cause codes 42,41, and 34.

Support Digit A to F

Select from drop down menu either False or True:

False (Default) - Do not support the digits 0x0a through 0x0f for translations and routing.

True - Support the digits 0x0a through 0x0f for translations and routing.

See the Digits 0x0A to 0x0F Support  link for more information.

Channel Transfer

Disabled (Default) - When disabled is selected, the Two Bearer Channel Transfer feature is disabled. If Channel Group Signaling Type is configured for a protocol other than ISDN, then this field cannot be changed.

Enabled - When the Signaling Type field in the channel group pane is set to ISDN, then the Transfer Mode field in the Channel Group Pane object pane can be changed to enabled. When Transfer Mode is enabled, the ISDN channel group is configured to send facility messages to the SPCS (Stored Program Control Switch) on the PBX or TDM Switch informing the TDM Switch/PBX to connect or loop two calls together. This will allow the two calls to be off-loaded from the IMG 2020.

Facility ATT TR50075 - When enabled, this will convert SIP REFER request directly into ISDN FACILITY message using the ATT Toll Free Transfer Connect Service (ATT TR50075). Refer to SIP Profile - Refer Support for more information.

Overlap Signaling

The fields Overlap Enable, Termination Digit, Minimum # of Digits, Inter SAM Timeout and Overlap Timeout all relate to Overlap Signaling only. See Overlap Signaling (Sending) and Overlap Signaling (Receiving) for more information.

Overlap Enable (Receiving) ISDN, SS7, and SIP

Disabled (default) - By default, the IMG 2020 passes only enbloc received digits to the outbound side.

Enabled - Enable overlap signaling on inbound Channel Groups when the outbound channel group does not support Overlap Signaling (SIP). The IMG 2020 will collect address digits until a Termination Condition is met and then continue call processing. See below for protocol-specific information. Overlap is only applied to the inbound channel, even on an Incoming/Outgoing Trunk.

Overlap Enable (Sending) SIP to SS7 Only

Disabled - Functionality is disabled.

Enabled- By enabling Overlap, this will allow Overlap Sending of destination address digits. In this case each received IAM and subsequent SAM messages will be interworked to a series of INVITES each containing all the destination address digits received to that point, similarly when the SIP interface receives a series of INVITES, each containing more destination address digits than the previous one, these will be mapped into an IAM, SAM sequence with each message containing only the 'new' digits from the latest INVITE.

Termination Digits

When Overlap Enable above is set to enabled, the IMG 2020 will collect digits until one of the termination digits selected in drop down menu is met. The termination digits are displayed below. The default termination digit is the pound sign (#) character.

Minimum # of Digits

When Overlap Enable is set to enabled, the IMG 2020 will collect digits on incoming channel group until the minimum number of digits selected is met. Once the minimum number is met, the IMG 2020 will attempt an outseize on the outgoing side. Range = 1-24 (default = 24).

Inter SAM (Subsequent Address Method) Timeout (ITU Only)

The SAM is used to send Subsequent Address Signals (digits) when overlap is being used for call setup. The Inter SAM Timeout is the amount of time to wait between receiving digits. The default is 1500 milliseconds (1.5 seconds) but can be modified by clicking in the Inter SAM Timeout box and entering the new value. The SAM is not used in ISDN call setup. 

Total Overlap Timeout

Max time allowed in seconds for call to be setup. Total Overlap timeout is used for both Minimum # of Digits or Inter SAM timeout. The Default is 18000 milliseconds (18 seconds) but can be modified by clicking in the Total Overlap Timeout box and entering the new value.

Multi-Level Precedence and Preemption (MLPP) Support

Multi-Level Precedence and Preemption is a priority scheme for assigning precedence levels to calls so the calls are handled in a pre-determined sequence/order and time frame. MLPP can preempt lower priority calls with pre-determined higher level priority calls. MLPP is supported for calls made between the ISDN and SIP protocols as well as between SIP and SIP protocols. For the feature to function, the MLPP field in both the ISDN Channel Group and the SIP Profile - Headers  object must be enabled. Refer to the Multi-Level Precedence and Preemption - MLPP topic for more in depth information such as call flows.

Disabled (Default)- The MLPP feature is disabled and calls will be processed normally.

Enabled- The MLPP feature is enabled. A precedence or priority level will be assigned to each call being processed. Calls that have a higher precedence level will preempt calls with a lower precedence. Once enabled in the ISDN channel group, the feature also needs to be enabled in the SIP Headers object.

Reserved Incoming Channels (%)

The Reserved Incoming Channels (%) field was added for the Dynamic Channel Reservation feature and configures an SS7 or ISDN channel group to have a percentage of the available channels configured as Incoming Only. The Reserved Incoming Channels (%) field is a drop down menu ranging from 0% to 100%.

Example:

If 10 was selected from the drop down menu of this field and the channel group has 32 channels in it. The number of channels reserved as Incoming Only will be: (10% * 32 = 3.2 Rounded up to the next whole number = 4).

In this case, 4 channels will be reserved as Incoming Only. For more information, refer to the Dynamic Channel Reservation topic.