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Telecom Decision CRTC 2006-34
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Ottawa, 26 May 2006 |
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Follow-up to Finalization of quality
of service rate rebate plan for competitors, Telecom Decision
CRTC 2005-20 – Service intervals
for provisioning CDN services and Type C loops
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Reference: 8638-C12-200505349 |
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In this Decision, the Commission
finalizes the service intervals for Competitor Digital Network (CDN)
services and Type C loops that competitors acquire from the incumbent
local exchange carriers (ILECs). These intervals are based on intervals
for similar services that the ILECs provide to their retail customers. |
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In addition, the Commission determines
that the service confirmation time is part of the service interval for
the delivery of a CDN service or Type C loop, and that noon in the
ILEC's serving territory is the cut-off reference time to calculate
these service intervals. |
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The Commission also adjusts service
intervals for TELUS Communications Company (TCC) so that, as with the
other ILECs' service intervals, they do not differ by the location
(urban/rural) where the CDN services and Type C loops are provisioned.
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Finally, Saskatchewan Telecommunications
and TCC are to review, reduce, and refile their service intervals for
all CDN services within one year of the date of this Decision in order
to align more closely with the other ILECs. |
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Background
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1.
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In Finalization of quality of service
rate rebate plan for competitors, Telecom Decision CRTC 2005-20,
31 March 2005 (Decision 2005-20),
the Commission introduced competition-related quality of service indicator
1.19, Confirmed Due Dates Met – CDN Services and Type C Loops. This
indicator measures the frequency with which the incumbent local exchange
carriers (ILECs) meet confirmed due dates for provisioning Competitor
Digital Network (CDN)1
services and Type C loops2
to competitors. The standard set for this indicator is 90 percent. |
2.
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The Commission notes that the record of
the proceeding that led to Decision 2005-20
did not include service intervals for CDN services or Type C loops.
In Decision 2005-20, the Commission
considered that the ILECs should provide services to their competitors
within timeframes similar to those they provided to themselves – that
is, to their retail customers – and initiated a follow-up process
to seek proposals from the ILECs to define service intervals for provisioning
CDN services and Type C loops. |
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Process
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3.
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The Commission made the following companies
parties to this proceeding: Aliant Telecom Inc. (Aliant Telecom), Bell
Canada, MTS Allstream Inc. (MTS Allstream), Saskatchewan
Telecommunications (SaskTel), and TELUS Communications Inc., now
TELUS Communications Company (TCC)3
(collectively, the ILECs); Société en commandite Télébec (Télébec); and
TELUS Communications (Québec) Inc. (formerly TELUS Québec, now TCC in
its Quebec operating territory). |
4.
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The Commission received proposals from Bell
Canada, MTS Allstream, SaskTel, TCC, and Télébec on 2 May 2005, and from
Aliant Telecom on 3 May 2005. MTS Allstream amended its proposal on 6
May 2005. |
5.
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The Commission received comments from MTS
Allstream (competitive local exchange carrier (CLEC))4
and Bell Canada (CLEC) on 10 and 11 May 2005, respectively. |
6.
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The Commission received reply comments from
Bell Canada, SaskTel, and TCC on 16 May 2005, and from Aliant Telecom on
18 May 2005. |
7.
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The Commission issued interrogatories to
the ILECs on 27 May 2005 and received responses on 10 June 2005 from
Bell Canada, MTS Allstream, SaskTel, and TCC. Aliant Telecom filed its
response on 19 October 2005, with the explanation that the delay was due
to an internal administrative error. |
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Issues
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8.
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In this proceeding the Commission has
considered three issues in order to establish service intervals for CDN
services and Type C loops. These issues are: |
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A. Service interval definition and cut-off time for triggering the
start of a service interval;
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B. Service intervals for CDN services and Type C loops where
facilities are available; and
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C. Service intervals for CDN services and Type C loops where
facilities are not available.
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A. Service interval definition and cut-off time for triggering the
start of a service interval
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Positions of parties
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9.
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All the ILECs except TCC submitted that
service intervals to provision CDN services and Type C loops should be
measured from the time that a firm order was received from the customer.
TCC submitted that the service interval began when it confirmed the
service order with the customer. |
10.
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TCC noted that TELUS Québec had not been
a party to the CDN service proceeding leading to Competitor Digital
Network Services, Telecom Decision CRTC 2005-6,
3 February 2005 (Decision 2005-6).
TCC submitted, therefore, that the CDN services and Type C loop service
intervals it proposed in this proceeding would not apply to requests
for service in the former TELUS Québec territory. |
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MTS Allstream (CLEC)'s comments
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11.
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MTS Allstream (CLEC) noted that while the
ILECs generally had proposed that the service intervals for CDN services
and Type C loops would be triggered by the receipt of a firm order, TCC
had proposed that these service intervals should begin once the service
order was entered into its provisioning system. MTS Allstream (CLEC)
argued that this approach could result in unreasonable delays if, for
example, the order entry position were understaffed. MTS Allstream
(CLEC) submitted that, consequently, these service intervals should not
be contingent on the date an order was entered into a particular ILEC's
database but should instead be triggered by the receipt of a firm order. |
12.
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MTS Allstream (CLEC) also submitted that
the time required by an ILEC to issue the confirmation of the firm
installation date for the ordered service should be included in the
service interval, as it was for all other services. |
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Reply comments
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13.
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In response to the comments by MTS
Allstream (CLEC) regarding the start of the service interval, Bell
Canada clarified that it considered day zero to be the calendar day that
the order was received from the customer, if the order was received
before 3 p.m. If the order was received after 3 p.m., the following
business day would be considered day zero. Bell Canada added that the
service intervals it had proposed included the time required to
determine the availability of facilities and provide a confirmed due
date to the customer. |
14.
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In response to MTS Allstream (CLEC)'s
concerns about what event should trigger the service interval, TCC
submitted that Aliant Telecom, Bell Canada, SaskTel, and TCC had all
adopted the position that the service interval started with the receipt
of a firm customer order. TCC also submitted that the period of
discussion and negotiation between the carrier and the customer prior to
the customer issuing a firm service order was clearly before the time
the service interval started. It suggested that the service interval
should only start once the customer had provided sufficient information
to enter the order into the provisioning system. |
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Commission's analysis and determinations
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15.
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The Commission notes that TELUS Québec
and Télébec were not directed to provide CDN services in Regulatory
framework for second price cap period, Telecom Decision CRTC 2002-34,
30 May 2002 (Decision 2002-34)
or in Decision 2005-6. Consequently,
TCC in its Quebec operating territory and Télébec will be required
to submit their provisioning service intervals for CDN services and
Type C loops in a future proceeding, when demand occurs in these operating
territories. |
16.
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The Commission notes that all the ILECs
except TCC proposed that the service intervals for CDN services and Type
C loops be triggered by the receipt of a firm order. TCC differed from
the other ILECs in proposing that the service interval be triggered by
the entry of the service order into its provisioning system. The
Commission considers that the triggering of a service interval should
not be contingent on an ILEC's specific provisioning process and
consequently considers TCC's service interval triggering proposal
inappropriate. |
17.
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With respect to MTS Allstream (CLEC)'s
request that the time required by an ILEC to issue the confirmation of
the firm installation date for the ordered service be included in the
service interval, the Commission considers that it is appropriate to be
consistent with current practice and include this period of time in the
service interval. |
18.
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The Commission notes that it has considered
the cut-off time for provisioning unbundled loops in various past
proceedings. A cut-off time of noon was adopted for local service
requests (LSRs) for migrated unbundled loops with a service interval
of two business days in Incumbent local exchange carrier service
intervals for unbundled local loop orders, Telecom Decision CRTC
2002-14, 8 March 2002 (Decision
2002-14). In addition, the Commission
notes that in an e-mail dated 29 August 2005, Commission staff proposed
to the CRTC Interconnection Steering Committee Business Process Working
Group participants that a cut-off time of noon should be adopted as
the start of the service interval for all services ordered via an
LSR. |
19.
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The Commission considers that a similar
approach should be used by ILECs when provisioning CDN services.
Consequently, if an order for a CDN service or a Type C loop is received
prior to or at noon in an ILEC's serving territory, that day will be
counted as day one. If the order is received after noon in the ILEC's
serving territory, the next business day will be counted as day one. The
Commission has adjusted Bell Canada's proposed service intervals
accordingly, resulting in a one-day increase based on the company's
current "day zero" counting process. These adjusted service intervals
are shown in the Appendix to this Decision. |
20.
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In light of the above, the Commission
determines that for a CDN service or Type C loop: |
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i) the service interval to provision a service is triggered by the
receipt by the ILEC of a firm order;
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ii) the interval of time required by the ILEC to confirm a due date
is part of the service interval; and
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iii) for consistency with its determination in Decision 2002-14
regarding LSRs for migrated unbundled loops, noon is the cut-off
reference time to calculate provisioning service intervals.
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B. Service intervals for CDN services and Type C loops where
facilities are available
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Positions of parties
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21.
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The ILECs submitted that where facilities
were available, their proposed service intervals for provisioning CDN
services and Type C loops to competitors were consistent with the
existing service intervals for their retail customers. |
22.
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The ILECs, with the exception of SaskTel,
which remained silent on the issue, added that any associated features
such as channelizing5
and intra-exchange or interexchange channels,6
when ordered with CDN access(es), would be provided within the same
service interval as the access(es), if the facilities required for
channelizing or for channel transport were available. They submitted
further that if these features were ordered separately, the service
intervals for these features alone would be the same as for the
access(es). |
23.
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Aliant Telecom proposed fixed service
intervals of 10 business days for provisioning CDN accesses or channels
at the DS-0 rate and 15 business days for provisioning accesses or
channels at DS-1, DS-3, OC-3, and OC-12 rates,7
within designated areas, where facilities and equipment were available.
It also proposed a service interval of 15 business days for Type C
loops, where facilities and equipment were available. |
24.
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Bell Canada proposed fixed service
intervals of between 7 and 12 business days for provisioning CDN
accesses or channels at DS-0, DS-1, DS-3, OC-3, and OC-12 rates, within
designated areas and where facilities were available. The company
clarified that the service interval of 7 business days was for Type C
loops delivered as an unchannelized DS-1, where facilities were
available. |
25.
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MTS Allstream proposed fixed service
intervals of between 12 and 30 business days for provisioning CDN
services at DS-0, DS-1, and DS-3 rates, where feeder and distribution
facilities were available. It also submitted that it currently does not
provide fixed delivery intervals for CDN services at OC-3 or OC-12 rates
in its territory due to lack of demand, but that it could reassess the
need for a fixed interval should demand for these services increase over
time. |
26.
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SaskTel proposed fixed service intervals
for provisioning CDN services at DS-0 and DS-1 rates of 12 and 20
business days, respectively, where facilities existed and within
designated service areas. SaskTel submitted that due to its lack of
experience in provisioning CDN services at higher rates, the service
interval would be negotiated with the customer. |
27.
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TCC proposed service intervals, where
facilities were available, of between 12 and 35 business days in
major/metro urban areas and minor urban areas, and between 15 and 45
business days in rural areas, for provisioning CDN services (accesses at
DS-0, DS-1 and fractional rates,8
and DS-3 rates), and from 12 to 30 business days in the same areas for
Type C loops. TCC also proposed service intervals in major/metro urban,
minor urban, and rural areas ranging from 20 to 45 business days for CDN
services (accesses) at OC-n rates. Finally, TCC proposed using the same
service intervals as the CDN-equivalent accesses for provisioning
private lines at 56 kb/s, DS-1, and DS-3 rates, and interexchange
channels at OC-n rates. |
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Bell Canada (CLEC)'s comments
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28.
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Bell Canada (CLEC) noted that while there
was a good degree of similarity in the service intervals proposed by the
ILECs, TCC had chosen to categorize service intervals as a function of
location. Bell Canada (CLEC) requested that the Commission require TCC
to propose service intervals for CDN services and Type C loops similar
to those proposed by the other ILECs in order to ensure standardization
of service across all territories where CLECs operated. Bell Canada
(CLEC) requested that, in the alternative, TCC be required to clearly
define the major/metro urban, minor urban, and rural areas by mapping
its own CDN/Digital Network Access (DNA) rate bands to each of the three
areas. |
29.
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Bell Canada (CLEC) also noted that the
service intervals proposed by TCC were almost four times longer than the
service intervals proposed by the other ILECs. Bell Canada (CLEC)
submitted that TCC's provisioning process should be in line with the
provisioning processes of the other ILECs, and that service intervals
for CDN services and Type C loops should be standardized across all
ILECs. |
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Reply comments
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30.
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SaskTel submitted that Bell Canada (CLEC)'s
proposal to standardize service intervals for all ILECs was self-serving
and should be rejected by the Commission since it did not specify which
of the ILECs' service intervals should serve as the standard or what
criteria should be employed to determine the appropriate standard. |
31.
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In response to Bell Canada (CLEC)'s
comments, TCC submitted that the service intervals it offered to its
retail and wholesale customers varied depending on the geographic region
in which it was asked to provide the service. TCC indicated that it had
technical staff residing in major urban areas who were readily available
to undertake new service requests, but that in rural areas it relied on
itinerant staff who undertook new service requests on a weekly or
biweekly basis, or as specifically scheduled. TCC indicated further that
provisioning equipment to deliver higher speed services was a more
lengthy process in rural areas than in urban areas. |
32.
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TCC submitted that it had divided its home
territory into three sub-areas in order to organize its workload and to
provide retail and wholesale customers with a reasonable expectation of
the time required to implement service. TCC submitted that it saw no
particular reason that it should accede to Bell Canada (CLEC)'s request
to offer the same service interval to a customer in downtown Edmonton as
to a customer requesting service in a newly discovered oil patch 100
kilometres outside the city. |
33.
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With respect to Bell Canada (CLEC)'s
request that TCC be required to clearly define its three geographic
areas by mapping its CDN/DNA rate bands to each of the three areas, TCC
noted that the major/metro urban areas were defined as the downtown
sections of Vancouver, Calgary, and Edmonton; the urban areas were
defined as the cities and locations within cities other than the three
specified above; and the rural areas encompassed the remaining parts of
its territory. TCC submitted that it would be prepared to clearly define
these areas by mapping its CDN/DNA rate bands to each of the three areas
once the Commission had ruled on its proposed sub-areas in this
proceeding. |
34.
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Concerning Bell Canada (CLEC)'s request to
standardize service intervals nationally, TCC submitted that a national
standardized service interval would not reflect local geography,
resource demographics, and other structural limitations that existed
within each company. TCC also submitted that the standardized approach
suggested by Bell Canada (CLEC) would not recognize the unique
circumstances faced by each company and was therefore impractical and
unworkable. |
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Commission's analysis and determinations
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35.
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The Commission notes that the ILECs
considered that the service intervals they proposed, where facilities
were available, were consistent with the service intervals they provided
to their retail customers for comparable services. MTS Allstream and
SaskTel did not propose service intervals for Type C loops. |
36.
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As noted earlier in this Decision, a Type C
loop is not a CDN service but is used to support DS-1 CDN service. The
Commission therefore considers it reasonable that the service intervals
for Type C loops should be equivalent to those for CDN services at the
DS-1 rate. |
37.
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Accordingly, the Commission determines that
MTS Allstream and SaskTel are to provision Type C loops within the same
service intervals as those approved in this Decision for CDN services at
the DS-1 rate, where facilities are available. |
38.
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The Commission notes that most ILECs, except
SaskTel, submitted that in the provisioning of CDN services, any associated
features such as channelizing and intra-exchange or interexchange
channels, when ordered with CDN access(es), would be provided within
the same service interval as the access(es), if the facilities required
for channelizing or channel transport were available. The Commission
also notes that for Bell Canada, two additional business days are
required to channelize a DS-1 access. The Commission further notes
that most ILECs submitted that if the associated features were ordered
separately, the applicable service interval would be the same as the
one that applied to the provisioning of the access(es). The Commission
notes that SaskTel's proposed service intervals for CDN services were
filed three months after Decision 2005-6
was issued and should therefore normally include the associated features. |
39.
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Accordingly, the Commission determines that
SaskTel is to provision associated features such as channelizing and
intra-exchange or interexchange channels within the same service
interval as access(es), in the same manner as most other ILECs, whether
these features are ordered with CDN access(es) or separately. |
40.
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The Commission notes further that where
facilities are available, MTS Allstream and SaskTel proposed that, due
to lack of demand or experience in provisioning high-rate CDN services,
service intervals be negotiated for high-rate accesses and interexchange
channels, which included OC-3 and OC-12 rates for MTS Allstream, and
DS-3, OC-3, and OC-12 rates for SaskTel. Parties to the proceeding did
not object to this proposal. The Commission agrees that service
intervals for OC-3 and OC-12, in the case of MTS Allstream, and for
DS-3, OC-3, and OC-12, in the case of SaskTel, should be negotiated when
these services are ordered in their operating territories. |
41.
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The Commission notes that if competitors'
attempts to negotiate such service intervals should fail, the
competitors may bring the matter before the Commission for resolution. |
42.
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The Commission notes that CDN services and
Type C loops are critical unbundled network elements required by CLECs
to compete with ILECs in the local service market in both rural and
urban areas. The Commission is concerned about the disparity that exists
between the service intervals TCC has proposed for CDN services and
those the other ILECs have proposed. TCC's proposed service intervals in
rural areas are in some cases more than twice as long as those in
major/metro urban areas and almost four times as long as other ILECs'
service intervals for similar services. |
43.
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The Commission notes that in Decision 2002-14,
it stated that it was satisfied that service intervals to provide
unbundled local loops should be the same for both urban and rural
areas since no rationale had been provided to justify longer service
intervals in rural areas. In addition, the Commission noted in that
decision that the ILECs had not demonstrated that service intervals
for their own customers in rural areas were longer than those in urban
areas. |
44.
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The Commission notes that in an
interrogatory dated 27 May 2005, it gave TCC an opportunity to provide
service intervals throughout its operating territory under the same two
categories as other ILECs. TCC's response was similar to its original
proposal in that service intervals for CDN services where facilities
were available were split into the same three previously proposed
geographic areas based on rate groups. TCC supported its unique proposal
using arguments such as geography and equipment delivery timeframes,
which might be equally applicable to the other ILECs, in addition to its
argument regarding specific workforce arrangements involving itinerant
workers. |
45.
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The Commission notes that, where facilities
are available, no differentiation was made in provisioning service
intervals between urban and rural areas by i) Aliant Telecom and Bell
Canada for CDN services at DS-n and OC-n rates, and for Type C loops;
ii) MTS Allstream for CDN services at DS-n rates and for Type C loops;
and iii) SaskTel for CDN services at DS-0 and DS-1 rates. TCC was the
only ILEC that proposed different service intervals for urban and rural
areas based on diverse geography, equipment availability and delivery
timeframes, and workforce arrangements. |
46.
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The Commission considers that the ILECs
generally face similar operating issues, including equipment
availability and delivery timeframes, diversity of geography, and
resource management. As a result, the Commission is not persuaded that
any ILEC requires a basis for establishing service intervals that is
completely different from the one used by the other ILECs to propose
service intervals for the same services. |
47.
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Consequently, the Commission determines
that where facilities are available, TCC is to use its proposed service
intervals for CDN services and Type C loops in major/metro urban areas
as the default for all of its operating territory outside Quebec. The
Commission has adjusted TCC's proposed service intervals accordingly, as
shown in the Appendix to this Decision. |
48.
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The Commission considers that with this
change, ILECs operating as CLECs in other ILECs' territories will
benefit from service intervals for unbundled network elements that are
similar to those they provide to CLECs operating in their own
territories. |
49.
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The Commission notes that even with this
change, TCC's service intervals for CDN services at rates higher than
DS-1 still remain longer than those proposed by all other ILECs. |
50.
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The Commission also notes that MTS
Allstream's and SaskTel's service intervals for CDN services at all
rates, and MTS Allstream's Type C loop service intervals, are
significantly longer than those proposed by Aliant Telecom and Bell
Canada for similar services. |
51.
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Consequently, the Commission determines
that MTS Allstream, SaskTel, and TCC are to review and reduce their
service intervals for CDN services and Type C loops that they provide to
their competitors to align more closely with the other ILECs. The
Commission directs MTS Allstream, SaskTel, and TCC to refile proposed
reduced service intervals within one year of the date of this Decision. |
52.
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In light of the above, the Commission
determines that where facilities are available: |
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i) the service intervals for CDN services and Type C loops, as
adjusted by the Commission and indicated in the Appendix to this
Decision, are approved, with an implementation date of 1 June 2006;
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ii) MTS Allstream and SaskTel are to provision Type C loops within
the same service intervals as those approved in this Decision for
their CDN services at the DS-1 rate;
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iii) SaskTel is to provision associated features such as
channelizing and intra-exchange or interexchange channels within the
same service interval as access(es), in the same manner as most other
ILECs, whether these features are ordered with CDN access(es) or
separately;
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iv) TCC is not permitted to adopt different service intervals for
urban and rural areas for CDN services and Type C loops, but is to
adopt the service intervals it proposed for its major/metro urban
areas as the default for all of its operating territory outside
Quebec. This has resulted in an adjustment of TCC's proposed service
intervals; and
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v) MTS Allstream, SaskTel, and TCC are to review, reduce, and
refile, within one year of the date of this Decision, the service
intervals for CDN services and Type C loops that they provide to their
competitors to align more closely with the other ILECs.
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C. Service intervals for CDN services and Type C loops where
facilities are not available
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Positions of parties
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53.
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The ILECs proposed that where facilities
are not available, service intervals should be negotiated with the
requesting competitor, similar to the current process with retail
customers. |
54.
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Aliant Telecom submitted that when network
construction was required, it would coordinate with equipment suppliers
and its construction department to establish the installation due date. |
55.
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SaskTel submitted that where facilities are
not available to provide DS-0 and DS-1 CDN services, the service
interval would be negotiated with the customer. SaskTel submitted
further that, due to its lack of experience in provisioning CDN services
at DS-3, OC-3, and OC-12 rates, the associated service intervals would
also have to be negotiated with the customer. |
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CLECs' comments
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56.
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The CLECs did not provide comments with
respect to cases where facilities are not available to provide CDN
services and Type C loops. |
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Commission's analysis and determinations
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57.
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The Commission notes that where facilities
are not available, all ILECs agreed that the service intervals should be
negotiated. |
58.
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The Commission notes that all ILEC tariffs
relative to the provision of unbundled loops and CDN services contain a
caveat that the provision of these facilities and services is contingent
on suitable facilities being available. |
59.
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The Commission notes that where facilities
required for CDN service or Type C loops are not available, ILECs need
to conduct economic studies before deciding to invest in a network
extension. They also need to design work plans, secure rights of way and
permits, and order equipment before building, testing, and putting the
new network into service. The Commission notes that many of these steps
are not completely within the ILECs' control. The Commission considers
that this supports the need for the ILECs and their customers to
negotiate the in-service date. |
60.
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As a result, the Commission considers that
it would not be appropriate to impose predetermined service intervals
where facilities are not available. |
61.
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The Commission notes that if competitors'
attempts to negotiate service intervals for CDN services or Type C loops
should fail, the competitors may bring the matter before the Commission
for resolution. |
62.
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In light of the above, the Commission
determines that where facilities are not available, service intervals to
provision CDN services and Type C loops should be negotiated between the
ILEC and its customer. |
63.
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Finally, the Commission notes that, as determined
in Decision 2005-6, ILECs have
included in their tariffs a provision to allow them to recover special
equipment costs and unusual expenses when installing equipment to
provide CDN services for competitors where facilities are not available. |
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Secretary General |
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This document is available in alternative
format upon request, and may also be examined in PDF
format or in HTML at the following Internet site: http://www.crtc.gc.ca
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Footnotes:
A Type C loop is a digital transmission path that can be used to support
a DS‑1 CDN service that connects an end customer to its service
provider's network. It is often ordered by competitive local exchange
carriers (CLECs) for other purposes and through a process that is
different from the one used to order the almost identical DS‑1 CDN
services.
"Rate" refers to a volume of bits over a unit of time [Kilo‑bits/s
(kb/s) or Mega‑bits/s (Mb/s)]. The term "speed" is often incorrectly
used instead of the word "rate."
"DS‑n" (Digital Signal Level n) is a signal format that operates at n
kb/s. DS‑n is the basic building block in the international digital
hierarchy. The number n is equal to 0 (DS‑0) when the signal format is
64 kb/s (or 56 kb/s), which is equivalent to a voice frequency channel.
It is equal to 1 (DS‑1) when the signal format is 1.544 Mb/s, which is
equivalent to 24 DS‑0s. It is equal to 3 (DS‑3) when the signal format
is 44.736 Mb/s, which is equivalent to 672 DS‑0s.
"OC‑n" (Optical Carrier Level n) is a term
used in the SONET (Synchronous Optical Network) hierarchy to identify
the transmission rate of the optical signals, transported in multiples
of 51.84 Mb/s. The SONET hierarchy is a North American standard for
synchronous optical networks having minimum transmission rates of 51.84
Mb/s. The number n is equal to 1 (OC‑1) when the system carries the
basic building‑block transmission of 51.84 Mb/s. It is equal to 3 (OC‑3)
when the transmission rate is 155.52 Mb/s, or three times OC‑1. It could
also be equal to 12, 48, 192, or 768.
8 In this case, the term "fractional rates" refers to two,
four, or eight DS‑0s.
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