Each ISUP Media Channel object is a child of an ISUP Remote Signaling Destination object.
This object contains configuration parameters and status information for an ISUP Media Channel. A Media Channel is defined for a set of Circuit Groups with the same local exchange and the same remote exchange and typically the same quality of service. A media channel is uniquely identified by the local and remote exchanges and a media channel index.
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Note that the MetaSwitch concept of a Media Channel corresponds closely to the DMS/5ESS Trunk Group; both define a collection of DS0s which may span multiple DS1s. |
Each media channel maintains a list of the associated circuit groups, each referenced by the CIC of the base circuit. Each associated circuit group references its associated media channel using the media channel index.
Routes are defined using Media Channels rather than individual circuit groups because it generates simpler routing tables.
There is no need to define an ISUP Media Channel for a one-way incoming trunk; it is required only for two-way or one-way outgoing trunks.
For initial configuration of an ISUP Media Channel, you need to do the following:
Parameter |
Access |
Description |
Media channel index | Create | Local index identifying the media channel. This index is referenced by the Circuit Groups which are associated with the media channel. |
Description | Change | A text string used in the EMS System Explorer to identify the media channel. Specify a string of up to 64 characters. |
Local trunk group number | Change inactive | The Trunk Group ID of the Media Channel. The primary use for this field is for billing records. When a call is set up using a circuit on this trunk group, the billing record output will indicate the trunk group's number. |
Allocation policy | Change Inactive | Specifies the circuit allocation policy to be used by the local exchange for allocating circuits within the media channel. (This should be different from the value used at the remote destination.) Values:
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Guard timer duration | Change Inactive | Duration, in ms, of the guard timer. The default is 750ms. |
Dual seizure policy | Change Inactive | Policy used to determine the dual seizure controlling exchange for circuits within this media channel. (This should be different from the value used at the remote destination.) Values:
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Echo cancellation | Change inactive | Echo cancellation requirements for this Media Channel. Echo cancellation can be set up either on a specific Media Channel (for example to use echo cancellation on a media channel that represents a satellite link), or in number validation (for example to use echo cancellation on all international calls).
Values:
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% utilization | Read only | Percentage utilization of the media channel; the number of allocated circuits as a percentage of the total number of circuits in the media channel. |
Disallow signaling for LRN | Change | This field is used to indicate whether the LRN or ported number is signaled in an IAM to the peer exchange for calls to US-style ported numbers.
Normally, for a call to a US-style ported number after LNP lookup, the called address parameter contains the LRN of the recipient exchange and the generic address (ported number) parameter contains the called address.
However, if this option is set to True, the generic address parameter is removed and the called address parameter is changed to be the actual called address rather than the LRN.
The IAM in this case is identical to the case where the NP lookup had not been done on this exchange but, importantly, it will still have been routed on the LRN rather than on the actual called address. Values:
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Record incoming CDRs | Change | Specifies whether to make billing records (known as Incoming Call Detail Records) for transit calls on this Media Channel. Values:
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Record outgoing CDRs | Change | Specifies whether to make billing records (known as Outgoing Call Detail Records) for transit calls on this Media Channel. Values:
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Append originating LRN module | Change | This field is used to indicate whether or not an originating LRN module should be appended to billing records generated for incoming calls on this trunk group if the appropriate information is available. Values:
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Connected-switch LRN | Change | This field is used to configure an LRN for the peer switch. This is used in generating billing records containing originating LRN information for incoming calls over this trunk group. For information about which LRN will be included, see Included LRN below. |
Override signaled LRN | Change | This field is used to determine whether or not the originating LRN configured on the trunk group should override the originating LRN received in a JIP parameter in a received IAM for billing purposes.
If no originating LRN is configured on the trunk group, this field is ignored. For information about which LRN will be included, see Included LRN below. Values:
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Generate incoming call CNA billing records | Change | This field is used to indicate when Connecting Network Access (CNA) billing records should be generated for incoming calls on this trunk group.
Values:
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CIC for CNA billing | Change | Carrier Identification Code to use in CNA billing records generated for incoming calls on this trunk group. This field is ignored when Generate incoming call CNA billing records is set to Never. Range: 0 - 9999. Default is 0. |
Include CNA billing number | Change | This field is the billing number which may be included in CNA billing records generated for incoming calls on this trunk group if Billing number for CNA billing is set to True. This field is ignored when Generate incoming call CNA billing records is set to Never. |
Billing number for CNA billing | Change | This field indicates whether or not the CNA billing number configured on the trunk group should be included in CNA billing records generated for incoming calls on this trunk group.
If this field is set to True and no CNA billing number is configured on the trunk group, the CNA billing record will the corresponding field with zeros.
This field is ignored when Generate incoming call CNA billing records is set to Never. Values:
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Include charge number | Change | This field indicates whether or not the charge number associated with the call should be included in CNA billing records generated for incoming calls on this trunk group.
This field is ignored when Generate incoming call CNA billing records is set to Never. Values:
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Include calling number | Change | This field indicates whether or not the calling number associated with the call should be included in CNA billing records generated for incoming calls on this trunk group.
This field is ignored when Generate incoming call CNA billing records is set to Never. Values:
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Use ISUP called address prefix information | Change | This field applies only if Enable ISUP called address prefix support on the ISUP Local Signaling Destination is True. Specifies whether the NE supports called address prefixes (NXZZ codes) for outgoing calls on this media channel. These prefixes may be required in Canada if this media channel supports long-distance locally-originated calls or tandem calls, but are not required for deployments elsewhere. (Prefixes on incoming calls are supported regardless of the setting of this field.) Values:
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Alarm state | Read only | Specifies whether any alarms are currently raised for this object. Values:
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Alarm log correlator - Attention Required | Read only | Identifier of the log message for the event that caused the last Attention Required alarm state for this object. This field is reset when the Attention Required alarm events field is reset to zero. |
Attention Required alarm events | Read only / Reset | Number of times (since the alarm count was reset) that this object's alarm state has gone to Attention Required. |
Alarm log correlator - Attend To Dependent | Read only | Identifier of the log message for the event that caused the last Attend To Dependent alarm state for this object. This field is reset when the Attend To Dependent alarm events field is reset to zero. |
Attend To Dependent alarm events | Read only / Reset | Number of times (since the alarm count was reset) that this object's alarm state has gone to Attend To Dependent. |
Alarm state changed timestamp | Read only | The time at which the Alarm state last changed. |
Alarm events reset timestamp | Read only | The time at which the Attention Required alarm events was last reset to zero. |
Requested status | Read only | Specifies whether an administrator has attempted to activate the ISUP Media Channel. Values:
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Actual status | Read only | Specifies the current status of the ISUP Media Channel. Values:
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When originating LRN information is included in billing records for incoming calls on this trunk, the actual LRN included is summarized in the following table.
LRN recv'd in JIP parm |
Configured LRN |
Override Sig LRN |
LRN value used |
No |
None |
FALSE |
None |
No |
None |
TRUE |
None |
No |
Value |
FALSE |
Configured LRN |
No |
Value |
TRUE |
Configured LRN |
Yes |
None |
FALSE |
Signaled LRN |
Yes |
None |
TRUE |
Signaled LRN |
Yes |
Value |
FALSE |
Signaled LRN |
Yes |
Value |
TRUE |
Configured LRN. |