Wholesale: Products & Services

Product Catalog (PCAT)

Commercial Resale - Integrated Services Digital Network (ISDN) Basic Rate Interface (BRI) - V1.0

History Log

Product Description

CenturyLink™'s retail telecommunications service, Integrated Services Digital Network (ISDN) Basic Rate Interface (BRI) is available for resale by Resale Customers to their end-users. Additional information about resale of CenturyLink's retail services can be found in Commercial Resale – General PCAT.

ISDN is an all-digital communications technology that provides services and capabilities not available through standard analog technology. The ISDN digital architecture provides a high-speed, integrated transfer of voice, data and video over the same line, using the Public Switched Network (PSN). CenturyLink's ISDN BRI is compatible with the National ISDN standards (NI-2) and International Telecommunications Union (ITU) standards and protocols and includes circuit-switched voice, circuit-switched data and packet functionality.

ISDN BRI provides for two simultaneous voice connections and a low speed data connection over existing telephone lines (twisted copper pair) which provides a 2-wire digital connection with a bandwidth of 144 kilobits per second (kbps) which is divided into three channels:

  • Two ‘B' channels capable of 64 kbps each. Each ISDN BRI channel is capable of switched voice and switched data transmissions, allowing two simultaneous separate 64 kbps connections of either type. B channels do not support packet switched data transmissions or out-of-band message signaling. Depending on the end-user's Customer Provided Equipment (CPE), the two B channels can be combined (bonded) into one high-speed 128 kbps link.
  • One ‘D' channel capable of 16 kbps. Each D channel supports out-of-band message signaling and packet data functionality but does not support voice applications. This channel can simultaneously route up to 15 data calls.

In each ISDN capable switch ISDN BRI configuration groups or capability packages are programmed into the ISDN BRI common block according to Telecordia National Standards. Telecordia ISDN Ordering Codes (IOCs) identify the different pre-programmed configuration groups or capability packages. The CPE vendor will work with you to select the appropriate IOC for your needs. If you require an ISDN BRI arrangement that is not supported by an IOC, you can request the specific arrangement of features and functions USOCs and FIDs to accommodate your needs.

The CenturyLink ISDN BRI standard feature package includes all standard features identified in the Tariffs/Catalogs/Price Lists provided the CPE can support the features. Contact the CPE vendor to determine if the CPE can support the standard features and to learn more about how they work with the CPE.


ISDN BRI is available where facilities exist throughout CenturyLink QC.

ISDN BRI is available in certain ISDN capable 5ESS and DMS-100 switches, and in some instances their remote switches. Other types of CO switches (such as DMS -10, Ericsson, etc.) do not have ISDN capability. Information describing how to determine ISDN BRI availability is described in Pre-Ordering.

It is your responsibility to provide CenturyLink with accurate end-user location information for state regulated emergency reasons. Information regarding the Enhanced 911 (E911) system is located in Access to Emergency Services (911/E911).

CenturyLink will accept one white page directory listing for each main telephone number at no charge. Additional information about directory listings is available in White Pages Directory Listings.

Additional terms and conditions, rates and charges can be found for each state in the Tariffs/Catalogs/Price Lists.

You may request a specific foreign serving office from which to receive ISDN BRI even if the end-user's serving wire center is equipped for ISDN BRI. You may request a foreign serving office because the end-user desires a certain prefix or to avoid long distance calls. You will be charged mileage charges for the service between the two wire centers.

Technical Publications

Technical characteristics are contained in the applicable Tariff and may have references to certain Technical Publications.


Rate Structure

CenturyLink retail rates and rate elements and how they apply to ISDN BRI can be found in the state specific Tariffs/Catalogs/Price Lists.

The Tariffs/Catalogs/Price Lists identify which ISDN BRI features CenturyLink defines as part of a standard feature package and which features are optional features. A configuration group or capability package may require some standard and some optional features to provision the required elements. If you require ISDN BRI features exceeding those identified as part of the CenturyLink standard feature package in the state specific Tariffs/Catalogs/Price Lists, the additional features will be charged as optional features.

A non-standard configuration charge applies per button (N3CPB) when establishing an ISDN BRI arrangement that is not supported by an IOC.


Retail rates can be found in the state specific Tariffs/Catalogs/Price Lists.

Tariffs, Regulations and Policies

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

Optional Features

ISDN BRI optional feature availability and pricing may vary according to the state specific Tariffs/Catalogs/Price Lists.

Optional features are available provided the CPE can support the features. Contact the CPE vendor to determine if the CPE can support the optional features and how they work with the CPE.

Optional feature descriptions and ordering information can be found in the Optional Features Ordering Information.

Additional information describing listings is available in White Pages Directory Listings.


    ISDN BRI provides three types of applications:
  • Voice only (circuit switched voice)
  • Voice and Data (includes circuit switched voice, circuit switched data, and packet switched data)
  • Data Only (includes circuit switched data and packet switched data)


Product Prerequisites

If you are a new Resale Customer and are ready to do business with CenturyLink, view Getting Started as a Commercial Reseller.


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

Requirements for pre-ordering are described in Local Service Ordering Guidelines (LSOG) Pre-Order.

New ISDN BRI telephone numbers can not be reserved in EASE-LSR. CenturyLink will return telephone numbers to you on the Firm Order Confirmation (FOC).

If your end-user wants to convert an existing non-ISDN telephone number to Resale ISDN BRI, check with your CenturyLink Service Manager to see if the telephone number can be converted. Even though the end-user's serving office has ISDN BRI available, not every prefix in the office may be compatible.

CenturyLink strongly suggests that you complete the ISDN loop qualification pre-ordering process in addition to the CO ISDN availability pre-ordering process. That way you will be able to determine if the ISDN BRI service is available to your end-user and if there are facilities available to provision the service.

ISDN BRI pre-qualification is a two step process.

Step one:

Verify the availability of ISDN BRI in the end-user's CO by referring to the Network Disclosures. Select the state for the end-user's CO location. If the ISDN BRI DATE column is populated with “Deployed,” ISDN BRI is available.

Step two:

Verify the ISDN loop availability of facilities at the end-user's address as described in the EASE-LSR User's Guide.

Please note that you can order ISDN BRI even if facilities are not available, however your order may be delayed.

Service is not guaranteed until the ISDN has actually been installed. There could be a rare instance where Facility Check cannot determine a design problem that would prevent installation of the single line service (SLS). In this situation, you would be notified by the receipt of a jeopardy notice. Additional information on the jeopardy process can be found in the Provisioning and Installation Overview.

Backhauling provides dialtone from an ISDN equipped switch that is not the end-users local serving wire center to the end-users local serving wire center. All backhauling requests should be referred to your CenturyLink Service Manager.


It is important to understand Commercial Resale - General procedures before ordering ISDN BRI.

General ordering activities are described in the Ordering Overview.

    ISDN BRI service requests are submitted using the following LSOG forms:
  • Local Service Request (LSR)
  • End User (EU)
  • Resale Service (RS)
  • Directory Listing (DL), if applicable

Field entry requirements are described in the LSOG.

Service requests should be placed using EASE-LSR Extensible Markup Language (XML) or EASE-LSR Graphical User Interface (GUI).

When requesting new ISDN BRI service enter the ISDN Ordering Code (IOC) obtained from the CPE vendor. The IOC must be entered in the FEATURES field on the RS form.

If an IOC is not available, you must enter the USOC and FID information required for your ISDN BRI arrangement in the FEATURE and FEATURE DETAILS fields of the RS form. For assistance in ordering refer to 5ESS Ordering Information or DMS-100 Ordering Information and Optional Features Ordering Information

To request Loop Conditioning, in the REMARKS field of the LSR form, include an entry of “Loop Conditioning authorized”. Without an entry in REMARKS, you have not authorized Loop Conditioning. If the service does not loop qualify and if you have not authorized Loop Conditioning the order will be rejected.

Provisioning and Installation

General provisioning and installation activities are described in the Provisioning and Installation Overview.

Upon receipt of an accurate and complete LSR including authorization of Loop Conditioning, you will receive a Firm Order Confirmation (FOC) based on the standard interval found in the Service Interval Guidelines (SIG). If at any time after you receive the FOC, and prior to the scheduled due date, CenturyLink determines that loop conditioning is required, CenturyLink will apply the Loop Conditioning interval and will re-FOC your LSR reflecting the new scheduled due date. The interval will begin on the date CenturyLink determines that loop conditioning is necessary and a supplemental LSR is not required.

If at any time after you receive the FOC, and prior to the scheduled due date, CenturyLink determines that the loop cannot be conditioned to loop qualify, you will receive a jeopardy notification via EASE-LSR. The jeopardy notification will provide you information on how to proceed.

Maintenance and Repair

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


Customer Records and Information System (CRIS) billing is described in Billing Information – Customer Records and Information System (CRIS).


View CenturyLink courses by clicking on Course Catalog.


CenturyLink contact information is located in Wholesale Customer Contacts.

Last Update: October 20, 2020