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 destination point codes 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.
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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Supported call directions | Change | Specifies whether this media channel can be used for incoming calls, outgoing calls, or both. 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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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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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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Receive gain | Change | Specifies the gain that should be applied to incoming voice calls on this media channel. (The receive gain is not applied to data calls.) This gain is applied only to calls that use DS1s on PB* adaptors, and not those on AM* or SG* adaptors. Note that changing this value will not apply the gain to existing calls, but will be applied to new calls that are set up after the change. You should ensure that you set this value in line with the loss plan, described by SR2275 and T1.506-1997 (R2001). Range: -12 to 12 dB. The default is zero (no gain is applied). Values outside of the range -6 to 6 dB can detrimentally affect voice quality, and prevent DTMF tone relay from functioning correctly. |
Billing - incoming terminating CDR type | Change | This field is hidden if Supported call directions is set to Outgoing. Specifies what CDR (if any) is output for incoming calls terminating on this NE using this ISUP Media Channel. Values:
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Billing - generate additional incoming call CDR | Change | This field is hidden if Supported call directions is set to Outgoing. Specifies whether an additional 119/0625 billing record should be output for incoming calls that are terminated locally, in addition to any CDR configured using the Billing - incoming terminating CDR type field. Values:
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Billing - incoming tandem CDR type | Change | This field is hidden if Supported call directions is set to Outgoing. Specifies what CDR (if any) is output for a tandem call routed through this NE using this ISUP Media Channel for the incoming leg. Values:
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Billing - outgoing originating CDR type | Change | This field is hidden if Supported call directions is set to Incoming. Specifies what CDR (if any) is output for outgoing calls originating from this NE using this ISUP Media Channel. Values:
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Billing - outgoing tandem CDR type | Change | This field is hidden if Supported call directions is set to Incoming. Specifies what CDR (if any) is output for a tandem call routed through this NE using this ISUP Media Channel for the outgoing leg. Values:
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CNA billing for incoming calls - CIC | Change | This field is visible only if Supported call directions is not set to Outgoing, and either Billing - incoming terminating CDR type or Billing - incoming tandem CDR type is set to CNA (720/0625) upon LNP query or CNA (720/0625) always. Specifies the Carrier Identification Code to use in CNA billing records generated for incoming calls on this ISUP Media Channel. Range: 0 - 9999. |
CNA billing for incoming calls - include CNA billing number | Change | This field is visible only if Supported call directions is not set to Outgoing, and either Billing - incoming terminating CDR type or Billing - incoming tandem CDR type is set to CNA (720/0625) upon LNP query or CNA (720/0625) always.
Specifies whether the billing number should be included in CNA billing records. Values:
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CNA billing for incoming calls - CNA billing number | Change | This field is visible only if Supported call directions is not set to Outgoing, CNA billing for incoming calls - include CNA billing number is set to True, and either Billing - incoming terminating CDR type or Billing - incoming tandem CDR type is set to CNA (720/0625) upon LNP query or CNA (720/0625) always. Specifies the billing number which may be output in CNA billing records generated for incoming calls on this ISUP Media Channel. Either leave this field blank, or specify a ten digit number. |
CNA billing for incoming calls - include charge number | Change | This field is visible only if Supported call directions is not set to Outgoing, and either Billing - incoming terminating CDR type or Billing - incoming tandem CDR type is set to CNA (720/0625) upon LNP query or CNA (720/0625) always.
Specifies whether the charge number should be included in CNA billing records. Values:
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CNA billing for incoming calls - include calling number | Change | This field is visible only if Supported call directions is not set to Outgoing, and either Billing - incoming terminating CDR type or Billing - incoming tandem CDR type is set to CNA (720/0625) upon LNP query or CNA (720/0625) always.
Specifies whether the calling number should be included in CNA billings records for incoming calls on this ISUP Media Channel. 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. |