1、 International Telecommunication Union ITU-T L.81TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (11/2009) SERIES L: CONSTRUCTION, INSTALLATION AND PROTECTION OF CABLES AND OTHER ELEMENTS OF OUTSIDE PLANT Monitoring systems for outside plant facilities Recommendation ITU-T L.81 Rec. ITU-T L.81 (11/2
2、009) i Recommendation ITU-T L.81 Monitoring systems for outside plant facilities Summary Natural disasters such as those caused by strong wind, flood, landslide, and earthquake happen more frequently than ever and their damage is increasing. Human-caused disasters such as those caused by fire, explo
3、sion, and collapse also happen on a large scale. Outside plant facilities including telecommunication buildings are exposed to these disasters and may be affected adversely, which implies that preventive measures are needed. Recommendation ITU-T L.81 deals with monitoring systems to mitigate damage
4、and to secure outside plant facilities against disasters. History Edition Recommendation Approval Study Group 1.0 ITU-T L.81 2009-11-13 15 Keywords Disaster, emergency management, monitoring system, structural health monitoring (SHM), wireless sensor network (WSN). ii Rec. ITU-T L.81 (11/2009) FOREW
5、ORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying
6、technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups wh
7、ich, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO an
8、d IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (t
9、o ensure e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words
10、 does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position conce
11、rning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by pa
12、tents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2010 All rights reserved. No part of this pub
13、lication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T L.81 (11/2009) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this Recommendation . 1 4 Abbreviations and acronyms 2 5 Conventi
14、ons 2 6 Disasters and emergency management for outside plant facilities . 2 6.1 Typical disasters . 2 6.2 Emergency management 2 6.3 Emergency management programs for outside plant facilities 3 6.4 Monitoring flow diagram . 4 7 Monitoring system for outside plant facilities 4 7.1 Objectives . 4 7.2
15、General requirements 5 7.3 Design considerations . 5 Appendix I Korean experience . 8 I.1 Monitoring system for outside plant facilities using WSN 8 I.2 Examples 8 Bibliography. 10 Rec. ITU-T L.81 (11/2009) 1 Recommendation ITU-T L.81 Monitoring systems for outside plant facilities 1 Scope This Reco
16、mmendation: describes typical emergency management for outside plant facilities; describes monitoring systems for outside plant facilities using wireless or wired network; provides an overview of disaster monitoring systems for outside plant facilities; provides design considerations for disaster mo
17、nitoring systems for outside plant facilities. It should be noted that fire disasters are not considered in this Recommendation because disaster management concerning fire is described in ITU-T L.20, ITU-T L.21 and ITU-T L.22. 2 References The following ITU-T Recommendations and other references con
18、tain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate t
19、he possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a
20、 Recommendation. ITU-T L.11 Recommendation ITU-T L.11 (1988), Joint use of tunnels by pipelines and telecommunication cables, and the standardization of underground duct plans. ITU-T L.20 Recommendation ITU-T L.20 (1996), Creation of a fire security code for telecommunication facilities. ITU-T L.21
21、Recommendation ITU-T L.21 (1996), Fire detection and alarm systems, detector and sounder devices. ITU-T L.22 Recommendation ITU-T L.22 (1996), Fire protection. ITU-T Y.1271 Recommendation ITU-T Y.1271 (2004), Framework(s) on network requirements and capabilities to support emergency telecommunicatio
22、ns over evolving circuit-switched and packet-switched networks. 3 Definitions 3.1 Terms defined elsewhere This Recommendation does not use any terms defined elsewhere. 3.2 Terms defined in this Recommendation This Recommendation defines the following terms: 3.2.1 disaster: Disasters are characterize
23、d by the scope of an emergency. An emergency becomes a disaster when it exceeds the capability of the local resources to manage it. Disasters often result in great damage, loss, or destruction. 3.2.2 early warning: The provision of timely and effective information, through identified institutions, t
24、hat allows individuals exposed to a hazard to take action to avoid or reduce their risk and prepare for effective response. 2 Rec. ITU-T L.81 (11/2009) 3.2.3 emergency: An emergency is a sudden, urgent, usually unexpected occurrence or event requiring immediate action. 3.2.4 structural health monito
25、ring (SHM): The process of continuously monitoring the status of a structure to detect damage. 3.2.5 wireless sensor network (WSN): A wireless network consists of spatially distributed autonomous devices using sensors to cooperatively monitor physical or environmental conditions, such as temperature
26、, sound, vibration, pressure, motion or pollutants, at different locations. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations: GSM Global System for Mobile Communications LAN Local Area Network SHM Structural Health Monitoring WAN Wide Area Network WSN Wireless Sensor
27、 Network 5 Conventions None. 6 Disasters and emergency management for outside plant facilities 6.1 Typical disasters Disasters are categorized into natural disasters and human-caused disasters. Natural disasters include those unplanned events that occur as a result of natural processes such as stron
28、g wind, flood, severe storm, landslide, earthquake, and tsunami. Human-caused disasters are those unplanned events or accidents that result from human activity or human developments, including urban fire, utility failures, collapse, explosion, and environmental disasters. 6.2 Emergency management Em
29、ergency management activities can be grouped into four phases as follows: Mitigation (Prevention): Activities that actually eliminate or reduce the probability of a disaster. Preparedness: Activities prior to an emergency that are used to support the prevention of, mitigation of, response to, and re
30、covery from emergencies. In this phase, plans are developed to save lives and minimize disaster damage (for example, installing early warning systems). Response: Activities following an emergency or disaster. These activities are designed to provide emergency assistance for victims, to stabilize the
31、 situation and to reduce the probability of secondary damage. Recovery: Activities necessary to return all systems to normal or better (for example, rebuilding destroyed property, or the repair of other essential infrastructure). Rec. ITU-T L.81 (11/2009) 3 6.3 Emergency management programs for outs
32、ide plant facilities To make outside plant facilities more reliable and stable against disasters, it is recommended that emergency management programs be provided. Typical examples of emergency management programs are listed in Table 1. Table 1 Typical examples of emergency management programs for o
33、utside plant facilities Disasters Potential consequences Possible preventive measuresa)Phaseb)Strong wind Overturning of telecommuni-cation poles or towers. Disconnection of cables. Observe design criteria for protection against strong wind. M Installation of supports (i.e., struts or guy line). P F
34、lood Immersion of telephone office and cable tunnels. Restrict installation in potential flood zones. M Installation of waterproof doors, water pump or monitoring system. P Landslide Duct bursts and disconnection of cables. Damage to outside plant facilities. Failures of earth retaining structures.
35、Restrict installation in potential landslide zones. M Periodic inspection. Monitoring by measurement. Installation of monitoring system. P Earthquake Destruction of telephone office including outside plant facilities. Breakdown of telecommunication equipments including Internet server. Duct bursts a
36、nd disconnection of cables. Secondary damages such as fire, shutting off electricity. Restrict installation in active earthquake fault. Legislation that requires earthquake-resistant building codes. M Installation of vibration controlling or mitigating system. Installation of SHM. P Lightning Breakd
37、own or failure of telecommunication equipments. Protection of outside plant against lightning-induced surges. P Collapse Destruction of telephone office and cable tunnels. Duct bursts and disconnection of cables. Observe building design criteria. Restrict new construction adjacent to existing outsid
38、e plant facilities. M Periodic inspection. Monitoring by measurement. Installation of SHM. P Excavation Disconnection of cables. Restrict new construction adjacent to existing underground cables. M Terror Fire. Explosion. Duct burst. Control entry personnel. Installation of monitoring system for sec
39、urity. P a)The above list of preventive measures is not exhaustive. b)M: Mitigation, P: Preparedness. Other emergency management phases such as response and recovery are not considered. 4 Rec. ITU-T L.81 (11/2009) 6.4 Monitoring flow diagram Manually operated monitoring procedures for outside plant
40、facilities are described in Figure 1-a. Patrolling and visual inspections are carried out by facility member staffs, and a detailed investigation follows when any defects are detected. If critical factors which may cause an accident are detected at this stage, additional safety assessment is carried
41、 out. As shown in Figure 1-b, monitoring systems by sensor network omit some of these stages, and thus make it labour-saving and efficient to maintain the outside plant facilities. In addition, monitoring systems allow facility member staffs to quickly find critical data that ensure outside plant fa
42、cilities operate 24 hours a day. Figure 1 Monitoring flow diagram: (a) manually operated monitoring method; (b) monitoring systems 7 Monitoring system for outside plant facilities 7.1 Objectives The objective of the monitoring system is to detect defects in an early stage, and to deliver warning mes
43、sages to disaster managers rapidly when the defects are not tolerant. These activities can be performed by persons, but it may cost much time and effort when the structures or facilities to be monitored are big and spatially scattered over a wide area. In addition, small defects that may cause great
44、 disasters are apt to be overlooked by only manual inspection. Therefore, it is required to establish more sophisticated countermeasures such as an early-warning monitoring system. Yes Monitoring systems No No No Yes Yes Yes Patrolling and visual inspections Detailed investigation Additional safety
45、assessment Response and action Problems ? Problems ? Problems ? Yes Additional safety assessment Response and action Problems ? No Problems ? (a) (b) NoRec. ITU-T L.81 (11/2009) 5 7.2 General requirements It is recommended that the monitoring system for outside plant facilities be: designed to carry
46、 out proper response action rapidly in the emergency; implemented by reliable, stable and proven technology not to give a false alarm; operated in real-time or near real-time manner; designed to provide alerting without delay for facility staff members; tested and verified before application and reg
47、ularly checked. 7.3 Design considerations 7.3.1 Wired/wireless systems Monitoring system for outside plant facilities is to sense the physical or environmental conditions by sensors, and then to notify facility staff members through the way of wired or wireless system. Comparisons between wired and
48、wireless systems are presented in Table 2. Wired system is recommended when a higher reliability is required. Table 2 Comparisons between wired and wireless system Type Advantages Disadvantages Wired system stable and proven technology. involves many long lengths of cable to cover the large spatial
49、distances; expensive to install; cables can fail due to exposure to the environment or potential damage during extreme events; long cables result in sensor signal degradation. Wireless system no cables are required for data transfer; system setup and maintenance cost can be remarkably reduced; in the case of partial system failure, the rest of the system is capable of performing its task independently. power and communication bandwidth a
