Tài liệu HDSL2/HDSL4 LoopShield™ Feature ppt

Overview DS1-based business services are under increased competitive price and customer service pressures. Many tariffs now contain Service Assurance Warranties that refund part or all of monthly service fees based on the length and number of DS1 service outages. Wireline service providers are also challenged with maintaining and improving the quality of T1 business services while facing aging copper facilities, outside plant weather conditions and reductions in force. The LoopShield ICT Fault Sectionalization feature for HDSL 2/4 circuits offers service providers the ability to remotely test and identify the distance to outside plant copper facility faults. HDSL technology has enabled the ability to isolate faults at locations 1,2, 5 and 6 for some time. The LoopShield ICT feature allows service providers to identify distance-to-fault in locations 3 and 4 as well which results in more accurate dispatch and shorter repair times. When a fault is detected, a command places the HDSL line unit in a single-ended metallic test to identify and localize the copper loop fault. Identify Distance-to-Faults for Opens, Shorts and Grounds Internal Cable Test (ICT) fault analysis methodology is deployed in the CO line unit. Using information from the HDSL2/HDSL4 transceiver chipsets, the CO line unit is capable of locating loop short and open conditions for loop fault analysis. The fault location distance from the CO will be returned when this test is initiated. Refer to the tables below for a summary on the distance accuracy to the detected fault. HDSL2 Fault Sectionalization Distance Accuracy HDSL4 Fault Sectionalization Distance Accuracy The main use of the LoopShield ICT feature is to determine whether the fault lies within the CO or in the outside plant. The higher resolution for the short loops will allow the operator to determine if the detected fault is within the Main Distribution Frame (MDF) or in the outside plant, and make the correct dispatch decision. For faults at longer distances, the resolution is lower. For faults beyond 9000ft on HDSL4, the fault type and distance are difficult to ascertain. Faults beyond 9000 feet are reported as a bad loop at 9000+ feet. The distance figure is given as a 26AWG equivalent length. The ICT response can also indicate the status of the system: if there is ground fault on the loop or no fault detected on the loop; if a locally powered remote unit is detected or if a bad remote unit is detected in the system. When the line unit receives the ICT command, the line unit will enter a test mode to perform Outside Plant HDSL2/HDSL4 LoopShield ™ Feature Fault Sectionalization APPLICATION NOTE www.adc.com • +1-952-938-8080 • 1-800-366-3891 The new HDSL2/4 Internal Cable Test (ICT) fault analysis feature enables greater dispatch accuracy that reduces Mean Time to Repair (MTTR) and operating expenses for DS1 circuits. Distance from CO Accuracy 0-1 kft ±100 ft 1-9 kft ±500 ft Distance from CO Accuracy 0-1 kft ±100 ft 1-9 kft ±500 ft over 9 kft not specified Central Office 3 4 6 Remote Unit Line Unit MDF 2 5 1 DS1 HDSL HDSL DS1 the loop fault test. If the power condition is a ground fault, the ICT algorithm cannot determine the location of the fault. A ground fault indicates a low ohm path-to-earth ground exists on at least one of the loops. This path-to-earth ground adversely affects the ICT results. Access Information Through Remote Network Management The LoopShield Fault Sectionalization feature is flexible and easy to use. There are four major interfaces on the HDSL2/4 line cards that can be used to access the ICT feature. • Facility Data Link (FDL) TL1 • Front panel Craft Screen • Management Card Screen • Management Card TL1 The FDL TL1 command can be accessed remotely by adding scripts to a network management system such as Telcordia’s INTAS ™ that has test head access to FDL or via ADC’s HiGain and LoopStar HDSL remote management capabilities. With easy access to the LoopShield ICT feature from a remote Network Operation Center, overall customer service will significantly improve. Dispatch Appropriate Technician to Improve Repair Time and Reduce OPEX Many trouble tickets for DS1 failures are often dispatched twice. A ticket is dispatched to a CO technician who cannot fix the problem but only isolates the trouble in the outside plant cable facility. The ticket is then turned back in and re-dispatched to an outside technician. This double dispatching greatly increases overall repair time as well as maintenance operating costs. Furthermore, many outside technicians go to the CO or customer location first to try and isolate the trouble. When they receive a reasonably accurate distance-to-fault initially, they are more likely to determine the source of the problem sooner with less travel time. By eliminating double dispatches and trips to multiple locations along the cable route, service providers can significantly reduce their MTTR and operating expenses associated with maintaining DS1 business services. Improved MTTR will also reduce the number of Service Assurance Warranty refunds that service providers have to pay. Summary The LoopShield HDSL2/4 ICT Fault Sectionalization feature offers Wireline service providers the ability to determine approximate distances to opens, shorts and grounds for their DS1circuits easily and remotely. Using this feature to eliminate double dispatches and travel time enables them to greatly improve MTTR and reduce operating expenses for some of their most critical customers. ADC Telecommunications, Inc., P.O. Box 1101, Minneapolis, Minnesota USA 55440-1101 Specifications published here are current as of the date of publication of this document. Because we are continuously improving our products, ADC reserves the right to change specifications without prior notice. At any time, you may verify product specifications by contacting our headquarters office in Minneapolis. ADC Telecommunications, Inc. views its patent portfolio as an important corporate asset and vigorously enforces its patents. Products or features contained herein may be covered by one or more U.S. or foreign patents. An Equal Opportunity Employer 1324716 5/05 Original © 2005 ADC Telecommunications, Inc. All Rights Reserved Web Site: www.adc.com From North America, Call Toll Free: 1-800-366-3891 • Outside of North America: +1-952-938-8080 Fax: +1-952-917-3237 • For a listing of ADC’s global sales office locations, please refer to our web site. APPLICATION NOTE . command, the line unit will enter a test mode to perform Outside Plant HDSL2/HDSL4 LoopShield ™ Feature Fault Sectionalization APPLICATION NOTE www.adc.com • +1-952-938-8080. Sectionalization feature is flexible and easy to use. There are four major interfaces on the HDSL2/4 line cards that can be used to access the ICT feature. •