Wholesale: Products & Services

Commingling and Unbundled Network Elements - Combinations (UNE-C) V6.0

History Log


Unbundled Network Element Combinations (UNE-C) offerings are combinations of Unbundled Network Elements (UNEs). The UNE combination that CenturyLink™ has defined as a standard product is Enhanced Extended Loop (EEL).

Commingling is the connecting, attaching or otherwise linking of a UNE, combination of UNEs and/or resale service, to one or more facilities or services that a requesting telecommunications carrier has obtained at wholesale from CenturyLink.

Examples of commingling may include the following arrangements:

  • A point-to-point commingled EEL is a UNE circuit connected to a Private Line circuit of the same bandwidth; and either the loop or the transport is ordered from either the Private Line Transport (PLT) or Special Access (SA) tariff. The connection between the tariffed service and the UNE service is made via a central office connecting channel (COCC). The COCC is ordered and billed with the tariffed service. A commingled EEL can also be an EEL Loop connected to a PLT/SA tariff multiplexed transport facility between CenturyLink wire centers. See Enhanced Extended Loop (EEL)

    • An EEL Loop connected to a PLT Transport circuit of the same bandwidth via COCC. See diagram A
    • EEL Transport connected to a PLT Channel Termination of the same bandwidth, serving an end-user customer premises, via a COCC. See diagram B

  • Loop Mux Combination (LMC) A CLEC may also request CenturyLink to commingle DS1 or DS0 analog voice grade LMC Unbundled Loops with DS3 or DS1 multiplexed facilities ordered by CLEC from CenturyLink’s PLT or SA tariffs.
    • LMC Loops connected to a tariffed PLT or SA multiplexed facility with no transport. See diagram D.

  • Unbundled Dedicated Interoffice Transport (UDIT).  A UDIT may be commingled with a PLT or SA circuit of the same bandwidth via a COCC. The COCC is ordered and billed with the PLT/SA circuit.  A UDIT may also be commingled with a PLT/SA multiplexed facility.
    • UDIT connected to a Private Line Transport circuit of the same bandwidth via a COCC.  See diagram E.

    • UDIT connected to a tariffed multiplexed facilty. See diagram F.


Competitive Local Exchange Carriers (CLECs) can request CenturyLink to combine UNEs or commingle UNEs or combinations of UNEs with facilities or services obtained at wholesale from CenturyLink, throughout CenturyLink’s 14-state local service territory.

Terms and Conditions

When you request a combination in the same LATA and state, CenturyLink will combine UNEs that are ordinarily combined in CenturyLink’s network, if facilities are available.  For defined UNE-C products such as EEL, you may request CenturyLink to build facilities if CLEC Requested UNE Construction (CRUNEC) is included in the terms and conditions of your Interconnection Agreement. 

In addition to the UNEs combinedby CenturyLink for you, CenturyLink shall permit you to combine any UNE provided by CenturyLink with another UNE provided by CenturyLink or with compatible network components provided by you or provided by third parties to you in order to provide services.  Provisioning and maintaining combinations of UNEs and other network components is your responsibility for end-to-end overall performance.

Any CenturyLink provided UNE-Combination that includes high capacity loop and transport requires CLEC certification of the Service Eligibility Criteria.Information regarding certification is located in Enhanced Extended Loop (EEL) under Product Prerequisites.

If your current Interconnection Agreement includes provisions for commingling, you may commingle UNEs, combinations of UNEs, and resale services with wholesale services and facilities (e.g., switched and special access services offered pursuant to Tariff); and request CenturyLink to perform the necessary functions to provision such commingling.  Commingling is the connecting, attaching, or otherwise linking of a UNE, or a combination of UNEs, to one or more facilities or services that the CLEC has obtained at wholesale from CenturyLink pursuant to any method other than unbundling under section 251(c)(3) of the Telecommunications Act, or the combination of a UNE, or UNE combination with one or more such wholesale services.

The CLEC will be required to provide the Connecting Facility Assignment (CFA) for the network demarcation (e.g., Collocation or multiplexing facilities) for each UNE, UNE Combination, resale or wholesale service when requesting CenturyLink to perform the commingling of such services.  CenturyLink will not deny access to a UNE on the grounds that the UNE or UNE Combination shares part of CenturyLink’s network with access services. 

All variations of commingling of services that include a high capacity loop or channel termination with any CenturyLink provided transport facility or service are subject to the Service Eligibility Criteria listed in the Terms and Conditions section of the Enhanced Extended Loop (EEL).

Services are available for commingling only in the manner in which they are provided in CenturyLink’s applicable product Tariffs, catalogs, and price lists.

Local Interconnection Services (LIS) Entrance Facilities and LIS Mid Span Meet POI facilities obtained pursuant to the Local Interconnection section of your Interconnection Agreement are not available for commingling.

To the extent that a CLEC requests CenturyLink to commingle a UNE or combination of UNEs with one or more facilities or services that the CLEC has obtained at wholesale from CenturyLink pursuant to a method other than unbundling under Section 251(c)(3) of the Telecommunications Act, CenturyLink will not be required to bill that wholesale circuit at multiple rates, otherwise known as ratcheting.  Such commingling will not affect the prices of UNEs or UNE Combinations involved.

An EEL multiplexed facility may be ordered and will be billed at the UNE rate if, and only if, all circuits connected to the multiplexer are UNE (EEL) Loops.  In all other situations the multiplexed facility will be ordered and billed pursuant to the appropriate CenturyLink product tariff, catalog or price list.

When two services are commingled, the service interval for each facility included in the commingled arrangement will apply. Performance measurements and\or remedies are not applicable to the total commingled arrangement but do apply to each facility or service ordered within the commingled arrangement.  Work performed by CenturyLink to provide commingled services that are not subject to standard provisioning intervals will not be subject to performance measures and remedies.  Provisioning intervals applicable to services included within a requested commingled service arrangement will not begin to run until the CLEC provides a complete and accurate service request, necessary CFAs to CenturyLink, and CenturyLink completes work required to perform the commingling that is in addition to work required to provision the service as a stand-alone facility or service.

Technical Publications

Technical characteristics, including Network channel/Network Channel Interface (NC/NCI™) codes, are described in Technical Publications for each specific UNE and/or tariffed product. 


Rate Structure

Monthly recurring rates for UNE-C products are based on the rate for each individual UNE included in the UNE-Combination. Recurring charges arebilled on a month-to-month basis.  Term contracts are not available.  Nonrecurring installation charges will also apply to all UNE-Combinations. 

Commingled arrangements’ recurring and nonrecurring charges will apply to the UNE or UNE-Combination as stated above; and will apply to the tariffed services, as they are offered in CenturyLink’s applicable product Tariffs, catalogs and price lists.


Rates for individual UNEs and currently defined UNE-C product offerings can be found in Exhibit A or the specific rate sheet in your Interconnection Agreement.  Rates for commingled tariffed services can be found in CenturyLink’s Tariffs/Catalogs/Price Lists.

Tariffs, Regulations and Policies

Tariffs, regulations and policies are located in the state specific Tariffs/Catalogs/Price Lists.

Optional Features

Optional features section does not apply to Commingling and Unbundled Network Elements - Combinations (UNE-C).

Features / Benefits

Features/Benefits section does not apply to Commingling and Unbundled Network Elements - Combinations (UNE-C).


Applications section does not apply to Commingling and Unbundled Network Elements - Combinations (UNE-C).



If you are a new CLEC and are ready to do business with CenturyLink, information is available in Getting Started as a Facility-Based CLEC. If you are an existing CLEC wishing to amend your Interconnection Agreement or your New Customer Questionnaire, you can find information in the Interconnection Agreement.

Before requesting a new UNE-Combination, your Interconnection Agreement (ICA) must contain provisional language that allows you to combine UNEs. Also, before submitting a request to commingle, your current ICA must include language that allows commingling. If this language does not currently exist in your Interconnection Agreement an amendment is required.

If your Interconnection Agreement contains combination language, CenturyLink will provision UNE-Combinations without requiring an amendment to your Interconnection Agreement, provided that all UNEs included in your UNE-Combination request and their appropriate recurring and nonrecurring rate elements, are contained in your current Interconnection Agreement.


General pre-ordering activities are described in the Pre-Ordering Overview.

Pre-ordering processes and requirements may vary depending on the combination of UNEs or commingling arrangement requested.


General ordering activities are described in the Ordering Overview.

If you are requesting a combination of UNEs not currently defined as a standard product by CenturyLink, you must use the Special Request (SR) Process.  Ordering processes and requirements may vary depending on the combination of UNEs requested.

Service interval guidelines are located in the Service Interval Guide (SIG).  When commingling circuits of the same or different bandwidth, you will find the intervals for the UNE circuit in the Resale, UNE and Interconnection Services SIG and the intervals for the PLT/SA circuit in the SIG for Access Services.

Specific ordering information for commingling UNEs and tariffed services of the same bandwidth is located in the individual UNE PCATs:

Provisioning and Installation

Provisioning informationand design requirements are described in the individual Technical Publications for each specific UNE and/or tariffed service.

Maintenance and Repair

General maintenance and repair activities are described in the Maintenance and Repair Overview.

CenturyLink recognizes the CLEC does not always have the ability to isolate trouble to the specific circuit when commingling two circuits of the same bandwidth; however, it remains the CLEC's responsibility to isolate the trouble to CenturyLink's network and provide those test results when reporting trouble. The CLEC may authorize optional testing on the commingled UNE circuit. The CLEC must provide overall test results across both circuits or authorize optional testing for the UNE circuit before opening a trouble ticket. Once trouble has been isolated to CenturyLink's network, the CLEC will open a repair ticket and provide the test results on the specific circuit the CLEC has reason to believe is in trouble. The CLEC will also provide the other commingled circuit ID. If no trouble is found on the reported circuit and the problem is isolated to the other commingled circuit, CenturyLink will contact the CLEC and request the CLEC to open a customer report (CR) on the other circuit. There will be no charges if the trouble is found in CenturyLink's network on either of the two commingled circuits: unless a dispatch was requested by the CLEC after no trouble found on the reported circuit.


Billing systems and functionality may vary depending on the combination of UNEs requested.


Local CenturyLink 101 "Doing Business With CenturyLink"

  • This introductory web-based training course is designed to teach the Local CLEC and Local Reseller how to do business with CenturyLink. It will provide a general overview of products and services, CenturyLink billing and support systems, processes for submitting service requests, reports, and web resource access information. Click here for Course detail and registration information.
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CenturyLink contact information is located in Wholesale Customer Contacts.

Frequently Asked Questions (FAQs)

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Last Update: March 30, 2015

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