1、Alliance for Telecommunications IndustrySolutionsNetwork Reliability Steering CommitteeFixing Facility Outages: Building theTools to Make It HappenFacilities Solution Team ReportResults and RecommendationsNovember 1997Team Leaders: John HealyLouis ScerboBellcore11. Executive SummaryFacility failures
2、 continue to be the leading contributor to outages in the Public Switched Network.Approximately 50% of the FCC-reportable1 service outages and their impact have been caused byfacility outages. The ATIS/NRSC2 Facilities Solution Team was chartered to determine the causesof those facility outages and
3、to recommend ways to reduce their number and impact.The Facilities Solution Team is made up of representatives of telecommunications service providers(InterExchange Carriers and Local Exchange Carriers), several large utilities, the insurance industry,contractors associations, and the Department of
4、Transportation (DOT). One of the major changesimplemented since February of 1996 has been the expansion of the membership to organizationsoutside the telecommunications industry. The major reason for the expansion was thataccomplishing the goals of Facilities Solution Team could not occur without th
5、e cooperation of allthe organizations involved with installing, maintaining, and using facilities. The team was brokeninto four subteams: the Data Analysis Subteam, the Damage Prevention Subteam, the LegislativeSubteam, and the New Technology Subteam.The Facilities Solution Team published a comprehe
6、nsive report of their findings andrecommendations in February 1996. The report entitled Keeping the Network Alive and Well:Solving the Problem of Cable Dig-Ups provided 24 recommendations on ways to reduce thenumber and impact of facility outages. This is the second report aimed at reducing the numb
7、er andthe impact of facility outages.Overall, the number of facility outages is down from the previous year. Of equal interest, the impactof facility outages is down:Report Year 37/1/95 - 6/30/96Report Year 47/1/96 - 6/30/97Number of Facility Outages 100 85Facility Outage Impact(Outage Index3)882 63
8、5Although these changes are not statistically significant, they indicate that progress has been made.The Data Analysis Subteam has developed a new categorization for facility outages. The goal wasto clarify the categories and to reduce the number of outages classified as “Other”. The newcategories a
9、re sub-terrestrial cable dig-ups, sub-terrestrial cable washout, sub-terrestrial cabledamage other, aerial cable cuts, submarine cable cuts, cable placing/removing, splices/connectors,cable electronics, radio facility equipment, and other. With the new categorization, the DataAnalysis Subteam determ
10、ined that cable electronics outages are higher in the last two years than in1 Per Federal Communications Commission CC Docket 91-273.2 Alliance for Telecommunications Industry Solutions/Network Reliability Steering Committee.3 Per Committee T1 Technical Report No. 42, Enhanced Analysis of FCC-Report
11、able Service Outage Data, August1995.2the previous three years and recommended that the Cable Electronics Subteam be resurrected tolook at these outages.The goal of the Cable Damage Prevention Subteam was to develop comprehensive proactiveguidelines which are non-legislative in nature and are aimed
12、at preventing facility outages.The Cable Damage Prevention Subteam completed the following four documents:1. Minimum Damage Prevention Guidelines - Excavation Procedures for UndergroundFacilities2. Minimum Performance Guidelines for One-Call Notification Systems3. Facility Owners Minimum Guidelines
13、for Location and Protection of Below GroundFiber Optic Cable4. Guidelines for Prospective Excavation Site Delineation and Facility Owner Markout.These guidelines define minimum standards for each of the parties with a role in damageprevention.Over 50% of the facility outages are categorized as Fiber
14、 Cut Dig-Ups. Nearly 50% of the Fiber CutDig-Ups occurred because the excavator either failed to notify the facility owner or providedinadequate notification. One-Call legislation is aimed at reducing these outages. The FacilitiesSolution Team recommended federal One-Call legislation in its earlier
15、report. In July, 1996,Casimir Skrzypczak, then President of NYNEX Science and Technology Inc., in his testimony insupport of One-Call legislation before a House Subcommittee, outlined four recommendedprinciples of One-Call legislation that the Facilities Solution Team continue to use today. Thesepri
16、nciples cover 1) notice and responsibility, 2) simplicity and flexibility, 3) broad applicability and4) industry funding.The Facilities Solution Team continues to champion One-Call legislation at the federal level and atthe state level. The Facilities Solution Team endorses the passage of strong and
17、 effective federalOne-Call legislation to set minimum standards for the states to achieve in administering One-Callsystems. There are two One-Call bills before Congress which work to achieve the goal of protectingunderground telecommunications facilities and meet the recommended principles of legisl
18、ation asstated by Mr. Skrzypczak. The Facilities Solution Team supports both bills and is working to ensurethat a One-Call bill is passed which applies to all excavators and facility providers4.The only way to ensure that recommendations are acted on is by constant vigilance and continued,dedicated
19、effort. Past work appears to be paying off. The Facilities Solution Team, as part of theATIS/NRSC, stands ready to help ensure that its recommendations are acted upon, to periodicallyanalyze the effectiveness of its recommendations, and to respond to any new reliability concerns thatarise on telecom
20、munications facilities.4 Update: The One-Call bill S. 1115 (see Appendix G) was passed unanimously by the U.S. Senate on November 9,1997.32. BackgroundIn 1991, the Federal Communications Commission (FCC) chartered the Network ReliabilityCouncil (NRC) to investigate causes of major outages in the tel
21、ecommunications network. Itsmission was to recommend practices aimed at reducing the number and impact of these outages.The NRC first considered seven areas critical to network reliability and created a correspondingfocus group in each area. They concentrated initially on fire, power, switching, sig
22、naling, DigitalCross-connect Systems (DCSs), essential services and fiber cables. In their report, the FiberCable Focus Group stated, “During 1992, fiber cable failures were the single largest cause ofnetwork outages affecting more than 50,000 customers for more than 30 minutes and accountedfor roug
23、hly as many outages as tandem and local switch equipment combined. As networks placeever increasing amounts of traffic over single fiber cables, the need to protect these vital facilitiesbecomes ever more clear and crucial to the industrys goal of raising system reliability.”The Fiber Cable Focus Gr
24、oup developed a set of recommendations aimed at reducing cable dig-ups. In June 1993, the NRC first published Network Reliability: A Report to the Nation thatcontained a description of all the recommendations from the focus groups including those fromthe Fiber Cable Focus Group. In addition, as foll
25、ow up to one of their recommendations, theTelecommunications Industry Benchmarking Consortium was formed and published their reportNetwork Protection Practices for Subsurface Facilities through the Alliance forTelecommunications Industry Solutions (ATIS) in June 1994.The NRC also chartered the Netwo
26、rk Reliability Steering Committee (NRSC) to monitor majornetwork outages on an ongoing basis. The NRSC is a standing committee of ATIS. The NRSChas published quarterly reports since 1993 and four annual reports.In the first years after the formation of the NRSC, the number and impact of facility out
27、agescontinued to grow at an alarming rate. As a response to this growth, a major recommendation ofthe 1994 NRSC Annual Report was to establish a Facilities Solution Team as an entity under theNRSC. The Facilities Solution Team was chartered in January 1995 by the NRSC to determinethe major causes of
28、 facility outages and recommend ways to reduce their number and impact.The Facilities Solution Team published a comprehensive report of their findings andrecommendations in February 1996. The report entitled Keeping the Network Alive and Well:Solving the Problem of Cable Dig-Ups provided 24 recommen
29、dations on ways to reduce thenumber and impact of facility outages. Appendix A provides a list of the recommendations fromthat earlier report.The following chart, published in Keeping the Network Alive and Well: Solving the Problem ofCable Dig-Ups and in the NRSC 1995 Annual Report, shows that at th
30、e time these reports cameout the number of facility outages was growing.4FCC-Reportable Service Outages (7/1/92-6/30/95) Number of Outages by Failure Category 613138187 51472202416951 1803418 17140 0301020304050607080Facility LocalSwitchCCS TandemSwitchCOPowerNaturalDisasterOther OverloadNumber of O
31、utages Baseline Year (7/1/92 - 6/30/93)Report Year 1 (7/1/93 - 6/30/94)Report Year 2 (7/1/94 - 6/30/95)Figure 1: Failure Categories vs. Number of OutagesThe recommendations in Keeping the Network Alive and Well: Solving the Problem of CableDig-Ups were aimed at turning around this trend of increasin
32、g outages. This report discusses thecurrent status of facility outages. It also discusses the results from three of the subteams aimed atcontinually reducing the number and impact of facility outages. First it discusses the newcategorization of facility outages, which was the major activity of the D
33、ata Analysis Subteam.The report then covers the work of the Damage Prevention Subteam which developed guidelinesfor the various groups involved in preventing damage to buried cable. The report also discussesthe ongoing work of the Legislative Team to get comprehensive federal One-Call legislationpas
34、sed.3. Team MembershipThe Facilities Solution Team is made up of representatives of telecommunications serviceproviders (InterExchange Carriers and Local Exchange Carriers), several large utilities, theinsurance industry, contracting organizations and the Department of Transportation (DOT). Oneof th
35、e major changes in the Facilities Solution Team has been the expansion of the membershipto leaders at National Utility Locating Contractors Association (NULCA), National UtilityContractors Association (NUCA), So-Deep, and the DOT. The major reason for the expansionwas that accomplishing the goals of
36、 Facilities Solution Team could not occur without thecooperation of all the organizations involved with installing, maintaining, and using facilities. Inaddition, many of the new members provided valuable new perspectives on ways to reduce cabledamage. A complete list of the team members is given be
37、low:5Name Company Name CompanyStu Megaw AGCA Don Brown CNA InsuranceCarolyn Gatov Ameritech Mary Jo Cooney DOTRick Canaday AThence the need for a new categorization.The need for a new categorization is best illustrated by an example. Figure 9 below shows the oldsubcategories of facility outages. It
38、is instructive because of its flaws. One of the largestcategories is entitled Other. In fact, 18% of the outages are classified as Other. In one NRSCquarterly report, the largest number of outages fell in the Other category. Generally, this is a clearindication that the current way of categorizing o
39、utages is ineffective. There is no clear pathforward when Other is an important category. It is impossible to come up with recommendationsto reduce Other outages.Facility Outages by Failure Subcategory Fiber Cut DU50%Fiber Cut NDU24%Other18%DCS5%Internal Power2%Synchronization1%Figure 9: Number of O
40、utages by Facility Failure SubcategoryFigure 9 also shows another major flaw in the old categorization of facility outages. For years,we had been using a category entitled Fiber Cut Non Dig-Up. In Figure 9 the number of FiberCut Non Dig-Ups is about 24% of all the outages. Unfortunately, this catego
41、ry is actually ahodgepodge of aerial cable cuts, washouts of underground cable, etc. Generally, categoriesshould be self-explanatory.12There were also several subcategories for which there were infrequent outages. An example isSynchronization. When the current categorization was developed, the plann
42、ers felt thatsynchronization problems might develop into a major cause of outages; this has not materialized.The solution is to eliminate Synchronization as a subcategory.The final problem with the facility categorization is related to Digital Cross-connect Systems(DCSs). DCS outages have been a sub
43、category of facility outages. Several experts have arguedfor the last few years that DCSs are complex network elements which are more similar toswitches than they are to components of transport facilities. In fact, one of the recommendationsof the first Network Reliability Council was to treat DCSs
44、like switches. If we accept thisreasoning, DCSs should have their own separate category just like local switches do.5.2 The New CategorizationThe new categorization of facility outages is: Sub-terrestrial cable dig-ups (DU) Sub-terrestrial cable “washout” Sub-terrestrial cable damage other (e.g., ro
45、dents, fire, vehicular accident) Aerial cable cuts Submarine cable cuts Cable placing/removing Splices/connectors (e.g., Lightguide Stranded Cable Interconnection EquipmentLSCIE) Cable electronics (e.g., repeaters, multiplexers add/drop, M31, SONET, etc.,demultiplexers, regenerators timing source in
46、terface unit, BITS interface card, voltagecontrol oscillator VCXO fuses, power unit) Radio facility equipment Other.The new categories are generally quite easy to understand. The new categorization reduces thenumber of outages that fit in the Other category. The new categorization eliminates the cat
47、egoryFiber Cut Non-Dig-Up which was relatively difficult to explain. In the new categorization, DCSoutages are no longer a subcategory of facility outages. DCS outages have their own category.Finally, synchronization no longer is a subcategory of facility outages.The results of applying the new cate
48、gorization are shown in the following pie chart:13Facility Outages by New Failure Subcategory Sub-terrestial DU56%Sub-terrestial Washout8%Radio3%Other1%Splices2%Aerial6%Submarine1%Cable Placing3%Sub-terrestial Damage Other8%Cable Electronics12%Figure 10: Percentage of Outages by New Facility Subcate
49、goriesNote that the percentage of outages in the Other subcategory has been reduced to 3%.The Facilities Solution Team will continue to examine the new categorization to ensure that itworks well. The new categorization should be used for all Network Reliability SteeringCommittee (NRSC) reports.Recommendation 2: Track and analyze facility outages using the new categorization offacility outages. Take action if any substantial negative trend arises or persists.Since 12% of the outages fell into the Cable Electronics subcategory, the Data Analysis Subteamlooked into this subcateg
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