§  51.319   Specific unbundling requirements.

   (a) Local loops. An incumbent LEC shall provide a requesting
   telecommunications carrier with nondiscriminatory access to the local
   loop on an unbundled basis, in accordance with section 251(c)(3) of the
   Act and this part and as set forth in paragraphs (a)(1) through (8) of
   this section. The local loop network element is defined as a
   transmission facility between a distribution frame (or its equivalent)
   in an incumbent LEC central office and the loop demarcation point at an
   end-user customer premises. This element includes all features,
   functions, and capabilities of such transmission facility, including
   the network interface device. It also includes all electronics,
   optronics, and intermediate devices (including repeaters and load
   coils) used to establish the transmission path to the end-user customer
   premises as well as any inside wire owned or controlled by the
   incumbent LEC that is part of that transmission path.

   (1) Copper loops. An incumbent LEC shall provide a requesting
   telecommunications carrier with nondiscriminatory access to the copper
   loop on an unbundled basis. A copper loop is a stand-alone local loop
   comprised entirely of copper wire or cable. Copper loops include
   two-wire and four-wire analog voice-grade copper loops, digital copper
   loops (e.g., DS0s and integrated services digital network lines), as
   well as two-wire and four-wire copper loops conditioned to transmit the
   digital signals needed to provide digital subscriber line services,
   regardless of whether the copper loops are in service or held as
   spares. The copper loop includes attached electronics using time
   division multiplexing technology, but does not include packet switching
   capabilities as defined in paragraph (a)(2)(i) of this section. The
   availability of DS1 and DS3 copper loops is subject to the requirements
   of paragraphs (a)(4) and (5) of this section.

   (i) Line splitting. An incumbent LEC shall provide a requesting
   telecommunications carrier that obtains an unbundled copper loop from
   the incumbent LEC with the ability to engage in line splitting
   arrangements with another competitive LEC using a splitter collocated
   at the central office where the loop terminates into a distribution
   frame or its equivalent. Line splitting is the process in which one
   competitive LEC provides narrowband voice service over the low
   frequency portion of a copper loop and a second competitive LEC
   provides digital subscriber line service over the high frequency
   portion of that same loop. The high frequency portion of the loop
   consists of the frequency range on the copper loop above the range that
   carries analog circuit-switched voice transmissions. This portion of
   the loop includes the features, functions, and capabilities of the loop
   that are used to establish a complete transmission path on the high
   frequency range between the incumbent LEC's distribution frame (or its
   equivalent) in its central office and the demarcation point at the
   end-user customer premises, and includes the high frequency portion of
   any inside wire owned or controlled by the incumbent LEC.

   (A) An incumbent LEC's obligation, under paragraph (a)(1)(i) of this
   section, to provide a requesting telecommunications carrier with the
   ability to engage in line splitting applies regardless of whether the
   carrier providing voice service provides its own switching or obtains
   local circuit switching from the incumbent LEC.

   (B) An incumbent LEC must make all necessary network modifications,
   including providing nondiscriminatory access to operations support
   systems necessary for pre-ordering, ordering, provisioning, maintenance
   and repair, and billing for loops used in line splitting arrangements.

   (ii) Line conditioning. The incumbent LEC shall condition a copper loop
   at the request of the carrier seeking access to a copper loop under
   paragraph (a)(1) of this section or a copper subloop under paragraph
   (b) of this section to ensure that the copper loop or copper subloop is
   suitable for providing digital subscriber line services, whether or not
   the incumbent LEC offers advanced services to the end-user customer on
   that copper loop or copper subloop. If the incumbent LEC seeks
   compensation from the requesting telecommunications carrier for line
   conditioning, the requesting telecommunications carrier has the option
   of refusing, in whole or in part, to have the line conditioned; and a
   requesting telecommunications carrier's refusal of some or all aspects
   of line conditioning will not diminish any right it may have, under
   paragraphs (a) and (b) of this section, to access the copper loop or
   the copper subloop.

   (A) Line conditioning is defined as the removal from a copper loop or
   copper subloop of any device that could diminish the capability of the
   loop or subloop to deliver high-speed switched wireline
   telecommunications capability, including digital subscriber line
   service. Such devices include, but are not limited to, bridge taps,
   load coils, low pass filters, and range extenders.

   (B) Incumbent LECs shall recover the costs of line conditioning from
   the requesting telecommunications carrier in accordance with the
   Commission's forward-looking pricing principles promulgated pursuant to
   section 252(d)(1) of the Act and in compliance with rules governing
   nonrecurring costs in § 51.507(e).

   (C) Insofar as it is technically feasible, the incumbent LEC shall test
   and report troubles for all the features, functions, and capabilities
   of conditioned copper lines, and may not restrict its testing to voice
   transmission only.

   (iii) Maintenance, repair, and testing. (A) An incumbent LEC shall
   provide, on a nondiscriminatory basis, physical loop test access points
   to a requesting telecommunications carrier at the splitter, through a
   cross-connection to the requesting telecommunications carrier's
   collocation space, or through a standardized interface, such as an
   intermediate distribution frame or a test access server, for the
   purpose of testing, maintaining, and repairing copper loops and copper
   subloops.

   (B) An incumbent LEC seeking to utilize an alternative physical access
   methodology may request approval to do so from the state commission,
   but must show that the proposed alternative method is reasonable and
   nondiscriminatory, and will not disadvantage a requesting
   telecommunications carrier's ability to perform loop or service
   testing, maintenance, or repair.

   (iv) Control of the loop and splitter functionality. In situations
   where a requesting telecommunications carrier is obtaining access to
   the high frequency portion of a copper loop through a line splitting
   arrangement, the incumbent LEC may maintain control over the loop and
   splitter equipment and functions, and shall provide to the requesting
   telecommunications carrier loop and splitter functionality that is
   compatible with any transmission technology that the requesting
   telecommunications carrier seeks to deploy using the high frequency
   portion of the loop, as defined in paragraph (a)(1)(i) of this section,
   provided that such transmission technology is presumed to be deployable
   pursuant to § 51.230.

   (2) Hybrid loops. A hybrid loop is a local loop composed of both fiber
   optic cable, usually in the feeder plant, and copper wire or cable,
   usually in the distribution plant.

   (i) Packet switching facilities, features, functions, and capabilities.
   An incumbent LEC is not required to provide unbundled access to the
   packet switched features, functions and capabilities of its hybrid
   loops. Packet switching capability is the routing or forwarding of
   packets, frames, cells, or other data units based on address or other
   routing information contained in the packets, frames, cells or other
   data units, and the functions that are performed by the digital
   subscriber line access multiplexers, including but not limited to the
   ability to terminate an end-user customer's copper loop (which includes
   both a low-band voice channel and a high-band data channel, or solely a
   data channel); the ability to forward the voice channels, if present,
   to a circuit switch or multiple circuit switches; the ability to
   extract data units from the data channels on the loops; and the ability
   to combine data units from multiple loops onto one or more trunks
   connecting to a packet switch or packet switches.

   (ii) Broadband services. When a requesting telecommunications carrier
   seeks access to a hybrid loop for the provision of broadband services,
   an incumbent LEC shall provide the requesting telecommunications
   carrier with nondiscriminatory access to the time division multiplexing
   features, functions, and capabilities of that hybrid loop, including
   DS1 or DS3 capacity (where impairment has been found to exist), on an
   unbundled basis to establish a complete transmission path between the
   incumbent LEC's central office and an end user's customer premises.
   This access shall include access to all features, functions, and
   capabilities of the hybrid loop that are not used to transmit
   packetized information.

   (iii) Narrowband services. When a requesting telecommunications carrier
   seeks access to a hybrid loop for the provision of narrowband services,
   the incumbent LEC may either:

   (A) Provide nondiscriminatory access, on an unbundled basis, to an
   entire hybrid loop capable of voice-grade service (i.e., equivalent to
   DS0 capacity), using time division multiplexing technology; or

   (B) Provide nondiscriminatory access to a spare home-run copper loop
   serving that customer on an unbundled basis.

   (3) Fiber loops--(i) Definitions--(A) Fiber-to-the-home loops. A
   fiber-to-the-home loop is a local loop consisting entirely of fiber
   optic cable, whether dark or lit, serving an end user's customer
   premises or, in the case of predominantly residential multiple dwelling
   units (MDUs), a fiber optic cable, whether dark or lit, that extends to
   the multiunit premises' minimum point of entry (MPOE).

   (B) Fiber-to-the-curb loops. A fiber-to-the-curb loop is a local loop
   consisting of fiber optic cable connecting to a copper distribution
   plant that is not more than 500 feet from the customer's premises or,
   in the case of predominantly residential MDUs, not more than 500 feet
   from the MDU's MPOE. The fiber optic cable in a fiber-to-the-curb loop
   must connect to a copper distribution plant at a serving area interface
   from which every other copper distribution subloop also is not more
   than 500 feet from the respective customer's premises.

   (ii) New builds. An incumbent LEC is not required to provide
   nondiscriminatory access to a fiber-to-the-home loop or a
   fiber-to-the-curb loop on an unbundled basis when the incumbent LEC
   deploys such a loop to an end user's customer premises that previously
   has not been served by any loop facility.

   (iii) Overbuilds. An incumbent LEC is not required to provide
   nondiscriminatory access to a fiber-to-the-home loop or a
   fiber-to-the-curb loop on an unbundled basis when the incumbent LEC has
   deployed such a loop parallel to, or in replacement of, an existing
   copper loop facility, except that:

   (A) The incumbent LEC must maintain the existing copper loop connected
   to the particular customer premises after deploying the
   fiber-to-the-home loop or the fiber-to-the-curb loop and provide
   nondiscriminatory access to that copper loop on an unbundled basis
   unless the incumbent LEC retires the copper loops pursuant to paragraph
   (a)(3)(iv) of this section.

   (B) An incumbent LEC that maintains the existing copper loops pursuant
   to paragraph (a)(3)(iii)(A) of this section need not incur any expenses
   to ensure that the existing copper loop remains capable of transmitting
   signals prior to receiving a request for access pursuant to that
   paragraph, in which case the incumbent LEC shall restore the copper
   loop to serviceable condition upon request.

   (C) An incumbent LEC that retires the copper loop pursuant to paragraph
   (a)(3)(iv) of this section shall provide nondiscriminatory access to a
   64 kilobits per second transmission path capable of voice grade service
   over the fiber-to-the-home loop or fiber-to-the-curb loop on an
   unbundled basis.

   (iv) Retirement of copper loops or copper subloops. Prior to retiring
   any copper loop or copper subloop that has been replaced with a
   fiber-to-the-home loop or a fiber-to-the-curb loop, an incumbent LEC
   must comply with:

   (A) The network disclosure requirements set forth in section 251(c)(5)
   of the Act and in § 51.325 through § 51.335; and

   (B) Any applicable state requirements.

   (4) DS1 loops. (i) Subject to the cap described in paragraph (a)(4)(ii)
   of this section, an incumbent LEC shall provide a requesting
   telecommunications carrier with nondiscriminatory access to a DS1 loop
   on an unbundled basis to any building not served by a wire center with
   at least 60,000 business lines and at least four fiber-based
   collocators. Once a wire center exceeds both of these thresholds, no
   future DS1 loop unbundling will be required in that wire center. A DS1
   loop is a digital local loop having a total digital signal speed of
   1.544 megabytes per second. DS1 loops include, but are not limited to,
   two-wire and four-wire copper loops capable of providing high-bit rate
   digital subscriber line services, including T1 services.

   (ii) Cap on unbundled DS1 loop circuits. A requesting
   telecommunications carrier may obtain a maximum of ten unbundled DS1
   loops to any single building in which DS1 loops are available as
   unbundled loops.

   (5) DS3 loops. (i) Subject to the cap described in paragraph (a)(5)(ii)
   of this section, an incumbent LEC shall provide a requesting
   telecommunications carrier with nondiscriminatory access to a DS3 loop
   on an unbundled basis to any building not served by a wire center with
   at least 38,000 business lines and at least four fiber-based
   collocators. Once a wire center exceeds both of these thresholds, no
   future DS3 loop unbundling will be required in that wire center. A DS3
   loop is a digital local loop having a total digital signal speed of
   44.736 megabytes per second.

   (ii) Cap on unbundled DS3 loop circuits. A requesting
   telecommunications carrier may obtain a maximum of a single unbundled
   DS3 loop to any single building in which DS3 loops are available as
   unbundled loops.

   (6) Dark fiber loops. An incumbent LEC is not required to provide
   requesting telecommunications carriers with access to a dark fiber loop
   on an unbundled basis. Dark fiber is fiber within an existing fiber
   optic cable that has not yet been activated through optronics to render
   it capable of carrying communications services.

   (7) Routine network modifications. (i) An incumbent LEC shall make all
   routine network modifications to unbundled loop facilities used by
   requesting telecommunications carriers where the requested loop
   facility has already been constructed. An incumbent LEC shall perform
   these routine network modifications to unbundled loop facilities in a
   nondiscriminatory fashion, without regard to whether the loop facility
   being accessed was constructed on behalf, or in accordance with the
   specifications, of any carrier.

   (ii) A routine network modification is an activity that the incumbent
   LEC regularly undertakes for its own customers. Routine network
   modifications include, but are not limited to, rearranging or splicing
   of cable; adding an equipment case; adding a doubler or repeater;
   adding a smart jack; installing a repeater shelf; adding a line card;
   deploying a new multiplexer or reconfiguring an existing multiplexer;
   and attaching electronic and other equipment that the incumbent LEC
   ordinarily attaches to a DS1 loop to activate such loop for its own
   customer. Routine network modifications may entail activities such as
   accessing manholes, deploying bucket trucks to reach aerial cable, and
   installing equipment casings. Routine network modifications do not
   include the construction of a new loop, or the installation of new
   aerial or buried cable for a requesting telecommunications carrier.

   (8) Engineering policies, practices, and procedures. An incumbent LEC
   shall not engineer the transmission capabilities of its network in a
   manner, or engage in any policy, practice, or procedure, that disrupts
   or degrades access to a local loop or subloop, including the time
   division multiplexing-based features, functions, and capabilities of a
   hybrid loop, for which a requesting telecommunications carrier may
   obtain or has obtained access pursuant to paragraph (a) of this
   section.

   (b) Subloops. An incumbent LEC shall provide a requesting
   telecommunications carrier with nondiscriminatory access to subloops on
   an unbundled basis in accordance with section 251(c)(3) of the Act and
   this part and as set forth in paragraph (b) of this section.

   (1) Copper subloops. An incumbent LEC shall provide a requesting
   telecommunications carrier with nondiscriminatory access to a copper
   subloop on an unbundled basis. A copper subloop is a portion of a
   copper loop, or hybrid loop, comprised entirely of copper wire or
   copper cable that acts as a transmission facility between any point of
   technically feasible access in an incumbent LEC's outside plant,
   including inside wire owned or controlled by the incumbent LEC, and the
   end-user customer premises. A copper subloop includes all intermediate
   devices (including repeaters and load coils) used to establish a
   transmission path between a point of technically feasible access and
   the demarcation point at the end-user customer premises, and includes
   the features, functions, and capabilities of the copper loop. Copper
   subloops include two-wire and four-wire analog voice-grade subloops as
   well as two-wire and four-wire subloops conditioned to transmit the
   digital signals needed to provide digital subscriber line services,
   regardless of whether the subloops are in service or held as spares.

   (i) Point of technically feasible access. A point of technically
   feasible access is any point in the incumbent LEC's outside plant where
   a technician can access the copper wire within a cable without removing
   a splice case. Such points include, but are not limited to, a pole or
   pedestal, the serving area interface, the network interface device, the
   minimum point of entry, any remote terminal, and the
   feeder/distribution interface. An incumbent LEC shall, upon a
   site-specific request, provide access to a copper subloop at a splice
   near a remote terminal. The incumbent LEC shall be compensated for
   providing this access in accordance with § § 51.501 through 51.515.

   (ii) Rules for collocation. Access to the copper subloop is subject to
   the Commission's collocation rules at § § 51.321 and 51.323.

   (2) Subloops for access to multiunit premises wiring. An incumbent LEC
   shall provide a requesting telecommunications carrier with
   nondiscriminatory access to the subloop for access to multiunit
   premises wiring on an unbundled basis regardless of the capacity level
   or type of loop that the requesting telecommunications carrier seeks to
   provision for its customer. The subloop for access to multiunit
   premises wiring is defined as any portion of the loop that it is
   technically feasible to access at a terminal in the incumbent LEC's
   outside plant at or near a multiunit premises. One category of this
   subloop is inside wire, which is defined for purposes of this section
   as all loop plant owned or controlled by the incumbent LEC at a
   multiunit customer premises between the minimum point of entry as
   defined in § 68.105 of this chapter and the point of demarcation of the
   incumbent LEC's network as defined in § 68.3 of this chapter.

   (i) Point of technically feasible access. A point of technically
   feasible access is any point in the incumbent LEC's outside plant at or
   near a multiunit premises where a technician can access the wire or
   fiber within the cable without removing a splice case to reach the wire
   or fiber within to access the wiring in the multiunit premises. Such
   points include, but are not limited to, a pole or pedestal, the network
   interface device, the minimum point of entry, the single point of
   interconnection, and the feeder/distribution interface.

   (ii) Single point of interconnection. Upon notification by a requesting
   telecommunications carrier that it requests interconnection at a
   multiunit premises where the incumbent LEC owns, controls, or leases
   wiring, the incumbent LEC shall provide a single point of
   interconnection that is suitable for use by multiple carriers. This
   obligation is in addition to the incumbent LEC's obligations, under
   paragraph (b)(2) of this section, to provide nondiscriminatory access
   to a subloop for access to multiunit premises wiring, including any
   inside wire, at any technically feasible point. If the parties are
   unable to negotiate rates, terms, and conditions under which the
   incumbent LEC will provide this single point of interconnection, then
   any issues in dispute regarding this obligation shall be resolved in
   state proceedings under section 252 of the Act.

   (3) Other subloop provisions--(i) Technical feasibility. If parties are
   unable to reach agreement through voluntary negotiations as to whether
   it is technically feasible, or whether sufficient space is available,
   to unbundle a copper subloop or subloop for access to multiunit
   premises wiring at the point where a telecommunications carrier
   requests, the incumbent LEC shall have the burden of demonstrating to
   the state commission, in state proceedings under section 252 of the
   Act, that there is not sufficient space available, or that it is not
   technically feasible to unbundle the subloop at the point requested.

   (ii) Best practices. Once one state commission has determined that it
   is technically feasible to unbundle subloops at a designated point, an
   incumbent LEC in any state shall have the burden of demonstrating to
   the state commission, in state proceedings under section 252 of the
   Act, that it is not technically feasible, or that sufficient space is
   not available, to unbundle its own loops at such a point.

   (c) Network interface device. Apart from its obligation to provide the
   network interface device functionality as part of an unbundled loop or
   subloop, an incumbent LEC also shall provide nondiscriminatory access
   to the network interface device on an unbundled basis, in accordance
   with section 251(c)(3) of the Act and this part. The network interface
   device element is a stand-alone network element and is defined as any
   means of interconnection of customer premises wiring to the incumbent
   LEC's distribution plant, such as a cross-connect device used for that
   purpose. An incumbent LEC shall permit a requesting telecommunications
   carrier to connect its own loop facilities to on-premises wiring
   through the incumbent LEC's network interface device, or at any other
   technically feasible point.

   (d) Dedicated transport. An incumbent LEC shall provide a requesting
   telecommunications carrier with nondiscriminatory access to dedicated
   transport on an unbundled basis, in accordance with section 251(c)(3)
   of the Act and this part, as set forth in paragraphs (d) through (d)(4)
   of this section. A "route" is a transmission path between one of an
   incumbent LEC's wire centers or switches and another of the incumbent
   LEC's wire centers or switches. A route between two points (e.g., wire
   center or switch "A" and wire center or switch "Z") may pass through
   one or more intermediate wire centers or switches (e.g., wire center or
   switch "X"). Transmission paths between identical end points (e.g.,
   wire center or switch "A" and wire center or switch "Z") are the same
   "route," irrespective of whether they pass through the same
   intermediate wire centers or switches, if any.

   (1) Definition. For purposes of this section, dedicated transport
   includes incumbent LEC transmission facilities between wire centers or
   switches owned by incumbent LECs, or between wire centers or switches
   owned by incumbent LECs and switches owned by requesting
   telecommunications carriers, including, but not limited to, DS1-, DS3-,
   and OCn-capacity level services, as well as dark fiber, dedicated to a
   particular customer or carrier.

   (2) Availability.

   (i) Entrance facilities. An incumbent LEC is not obligated to provide a
   requesting carrier with unbundled access to dedicated transport that
   does not connect a pair of incumbent LEC wire centers.

   (ii) Dedicated DS1 transport. Dedicated DS1 transport shall be made
   available to requesting carriers on an unbundled basis as set forth in
   paragraphs (d)(2)(ii)(A) and (B) of this section. Dedicated DS1
   transport consists of incumbent LEC interoffice transmission facilities
   that have a total digital signal speed of 1.544 megabytes per second
   and are dedicated to a particular customer or carrier.

   (A) General availability of DS1 transport. Incumbent LECs shall
   unbundle DS1 transport between any pair of incumbent LEC wire centers
   except where, through application of tier classifications described in
   paragraph (d)(3) of this section, both wire centers defining the route
   are Tier 1 wire centers. As such, an incumbent LEC must unbundle DS1
   transport if a wire center at either end of a requested route is not a
   Tier 1 wire center, or if neither is a Tier 1 wire center.

   (B) Cap on unbundled DS1 transport circuits. A requesting
   telecommunications carrier may obtain a maximum of ten unbundled DS1
   dedicated transport circuits on each route where DS1 dedicated
   transport is available on an unbundled basis.

   (iii) Dedicated DS3 transport. Dedicated DS3 transport shall be made
   available to requesting carriers on an unbundled basis as set forth in
   paragraphs (d)(2)(iii)(A) and(B) of this section. Dedicated DS3
   transport consists of incumbent LEC interoffice transmission facilities
   that have a total digital signal speed of 44.736 megabytes per second
   and are dedicated to a particular customer or carrier.

   (A) General availability of DS3 transport. Incumbent LECs shall
   unbundle DS3 transport between any pair of incumbent LEC wire centers
   except where, through application of tier classifications described in
   paragraph (d)(3) of this section, both wire centers defining the route
   are either Tier 1 or Tier 2 wire centers. As such, an incumbent LEC
   must unbundle DS3 transport if a wire center on either end of a
   requested route is a Tier 3 wire center.

   (B) Cap on unbundled DS3 transport circuits. A requesting
   telecommunications carrier may obtain a maximum of 12 unbundled DS3
   dedicated transport circuits on each route where DS3 dedicated
   transport is available on an unbundled basis.

   (iv) Dark fiber transport. Dark fiber transport consists of unactivated
   optical interoffice transmission facilities. Incumbent LECs shall
   unbundle dark fiber transport between any pair of incumbent LEC wire
   centers except where, through application of tier classifications
   described in paragraph (d)(3) of this section, both wire centers
   defining the route are either Tier 1 or Tier 2 wire centers. An
   incumbent LEC must unbundle dark fiber transport if a wire center on
   either end of a requested route is a Tier 3 wire center.

   (3) Wire center tier structure. For purposes of this section, incumbent
   LEC wire centers shall be classified into three tiers, defined as
   follows:

   (i) Tier 1 wire centers are those incumbent LEC wire centers that
   contain at least four fiber-based collocators, at least 38,000 business
   lines, or both. Tier 1 wire centers also are those incumbent LEC tandem
   switching locations that have no line-side switching facilities, but
   nevertheless serve as a point of traffic aggregation accessible by
   competitive LECs. Once a wire center is determined to be a Tier 1 wire
   center, that wire center is not subject to later reclassification as a
   Tier 2 or Tier 3 wire center.

   (ii) Tier 2 wire centers are those incumbent LEC wire centers that are
   not Tier 1 wire centers, but contain at least 3 fiber-based
   collocators, at least 24,000 business lines, or both. Once a wire
   center is determined to be a Tier 2 wire center, that wire center is
   not subject to later reclassification as a Tier 3 wire center.

   (iii) Tier 3 wire centers are those incumbent LEC wire centers that do
   not meet the criteria for Tier 1 or Tier 2 wire centers.

   (4) Routine network modifications. (i) An incumbent LEC shall make all
   routine network modifications to unbundled dedicated transport
   facilities used by requesting telecommunications carriers where the
   requested dedicated transport facilities have already been constructed.
   An incumbent LEC shall perform all routine network modifications to
   unbundled dedicated transport facilities in a nondiscriminatory
   fashion, without regard to whether the facility being accessed was
   constructed on behalf, or in accordance with the specifications, of any
   carrier.

   (ii) A routine network modification is an activity that the incumbent
   LEC regularly undertakes for its own customers. Routine network
   modifications include, but are not limited to, rearranging or splicing
   of cable; adding an equipment case; adding a doubler or repeater;
   installing a repeater shelf; and deploying a new multiplexer or
   reconfiguring an existing multiplexer. They also include activities
   needed to enable a requesting telecommunications carrier to light a
   dark fiber transport facility. Routine network modifications may entail
   activities such as accessing manholes, deploying bucket trucks to reach
   aerial cable, and installing equipment casings. Routine network
   modifications do not include the installation of new aerial or buried
   cable for a requesting telecommunications carrier.

   (e) 911 and E911 databases. An incumbent LEC shall provide a requesting
   telecommunications carrier with nondiscriminatory access to 911 and
   E911 databases on an unbundled basis, in accordance with section
   251(c)(3) of the Act and this part.

   (f) Operations support systems. An incumbent LEC shall provide a
   requesting telecommunications carrier with nondiscriminatory access to
   operations support systems on an unbundled basis, in accordance with
   section 251(c)(3) of the Act and this part. Operations support system
   functions consist of pre-ordering, ordering, provisioning, maintenance
   and repair, and billing functions supported by an incumbent LEC's
   databases and information. An incumbent LEC, as part of its duty to
   provide access to the pre-ordering function, shall provide the
   requesting telecommunications carrier with nondiscriminatory access to
   the same detailed information about the loop that is available to the
   incumbent LEC.

   [ 68 FR 52295 , Sept. 4, 2003, as amended at  68 FR 64000 , Nov. 12, 2003;
    69 FR 54591 , Sept. 9, 2004;  69 FR 77953 , Dec. 29, 2004;  70 FR 8953 ,
   Feb. 24, :78 2005 FR 5746 , Jan. 28, 2013]