WAC 480-120-401
Network performance standards. (1) All
companies must meet the applicable network performance
standards set forth in this section. The standards applied to
each service quality measurement are the minimum acceptable
quality of service under normal operating conditions. All
performance standards apply to each central office
individually and must be measured at or below that level. The
performance standards do not apply to abnormal conditions,
including, but not limited to work stoppage directly affecting
provision of service in the state of Washington, holidays,
force majeure, or major outages caused by persons or entities
other than the local exchange company (LEC) or its agents.
(2) Switches. End-office switches, in conjunction with
remote switches where deployed, must meet the following
standards:
(a) Dial service. For each switch, companies must meet
the following minimum standards during the switch's average
busy-hour of the average busy season:
(i) Dial tone must be provided within three seconds on at
least ninety-eight percent of calls placed; and
(ii) Ninety-eight percent of calls placed must not
encounter an intraswitch blocking condition within the central
office, or blocking in host-remote, or interoffice local
trunks.
(b) Intercept. Central office dial equipment must
provide adequate access to an operator or to a recorded
announcement intercept to all vacant codes and numbers. Less
than one percent of intercepted calls may encounter busy or
no-circuit-available conditions during the average busy-hour,
of the busy-season.
(3) Interoffice facilities. Blocking performance during
average busy-hour for ninety-nine percent of trunk groups for
any month must be less than one-half of one percent for
intertoll and intertandem facilities and less than one percent
for local and EAS interoffice trunk facilities. The blocking
standard for E911 dedicated interoffice trunk facilities must
be less than one percent during average busy-hour of the
average busy season. Two consecutive months is the maximum
that a single trunk group may be below the applicable
standard.
(4) Outside plant.
(a) Local loops. Each LEC must design, construct, and
maintain subscriber loops to the standard network interface or
demarcation point as follows:
(i) For voice grade, local exchange service loops must
meet all performance characteristics specified in Section 4 of
the Institute of Electrical and Electronic Engineers (IEEE)
Standard Telephone Loop Performance Characteristics.
Information about this standard regarding the version adopted
and where to obtain it is set forth in WAC 480-120-999.
(ii) For voice grade service, the circuit noise level on
customer loops measured at the customer network interface must
be equal to or less than 20.0 dBrnC, except that digitized
loops and loops in excess of 18,000 feet must have a noise
level objective of less than 25.0 dBrnC, and noise levels must
not exceed 30 dBrnC.
(b) Special circuits. Off-premise station circuit loss
must not exceed 5.0 dB at 1004 Hz when measured between the
customer switch demarcation and the customer station
demarcation. LECs with over fifty thousand access lines must
maintain design criteria for special circuits. Companies must
make channel performance criteria available to customers upon
request.
(c) Digital services. LECs must meet the availability
objectives for digital private line circuit performance
specified in the American National Standards for
Telecommunications, "Network Performance Parameters for
Dedicated Digital Services - Specifications." Information
about this standard regarding the version adopted and where to
obtain it is set forth in WAC 480-120-999. Upon request of a
customer, a LEC may provide to that customer digital services
that do not meet the performance standards set forth in (b) of
this subsection.
(5) Service to interexchange carriers. LECs must provide
service to interexchange carriers at the grade of service
ordered by the interexchange carrier. At a minimum, each
interexchange carrier must order sufficient facilities from
each LEC such that no more than two percent of all calls are
blocked at the LEC's switch.
(6) Companies must monitor the network performance of the
equipment they own, operate, or share at frequent intervals so
that adequate facilities can be designed, engineered and
placed in service when needed to meet the standards of this
section.
(7) Each Class A LEC must arrange and design incoming
trunks to the primary repair service center so that traffic
overflows during service interruptions can be redirected or
forwarded to an alternate repair or maintenance service center
location.
[Statutory Authority: RCW 80.01.040 and 80.04.160. 03-01-065
(Docket No. UT-990146, General Order No. R-507), §
480-120-401, filed 12/12/02, effective 7/1/03.]