Tài liệu N ETWORK EQUIPMENT BUILDING docx

N ETWORK E QUIPMENT B UILDING S YSTEM (NEBS) C RITERIA T ECHNICAL B RIEF Introduction As more and more carriers jump into the telecommunications arena providing T1 services, the amount of equipment to supply these services to customers is dramatically increasing. And the number of manufacturers who provide equipment to the carriers is exploding at an even more rapid pace. Some of these new suppliers have never made equipment for the public telecommunications network before. Their equipment has resided only in the highly-controlled environment of computer and data processing rooms, and their inexperience with the rigors of the less controlled Central Office (CO) and outside plant facility environments has resulted in reliability and operability problems. One carrier has even experienced a meltdown due to equipment not properly designed for the facility's environment. Another major concern is that the space to house this new equipment is becoming more and more limited. Rather than build new CO facilities to house the additional equipment, Competitive Local Exchange Carriers CLECs) are collocating their equipment in existing Regional Bell Operating Company (RBOC) and other Incumbent Local Exchange Carriers (ILECs) facilities. This collocation is a result of the industry deregulation started in the early 80's, which forces the ILECs to provide facility and equipment plant space to CLECs. 2 10/97 451 Network Equipment Building System Criteria What are the NEBS Criteria While the RBOCs and other ILECs are required by law to rent space to CLECS, typically in 10 foot x 10 foot increments, the incumbents aren't allowing just any old equipment in their facilities. Their number 1 concern is a fire or other catastrophe, caused by competitor's equipment, disrupting their network operation. To ensure network integrity and equipment compatibility, the incumbents have estab- lished a set of guidelines that service providers and equipment suppliers must comply with before the equipment can be installed in their facilities. These criteria are called Network Equipment-Building System criteria, or NEBS for short. In the 1970's, Bell Laboratories originated the concept of a Network Equipment-Building System document, a set of guidelines aimed at equipment manufacturers to help focus product design. The expectation was that designing equipment to be compatible with a specific set of physical configurations and environmental conditions would ensure network integrity and equipment compatibility, as well as reduce product development, installation, and maintenance costs. Bellcore introduced the original NEBS document in the mid-80's, with its audience the growing number of manufacturers supplying CO equipment to RBOCs. In the latest version of NEBS, two separate documents cover both physical and electrical criteria. Despite the division of physical and electrical criteria into two separate documents, most users consider NEBS criteria as a single family of requirements. GR-63-CORE, Network Equipment Building System (NEBS) Requirements: Physical Protection, Issue 1, October 1995 The physical criteria include the following specifications: · Space Planning: physical envelope and installation requirements · Temperature: safe operating temperature range · Humidity: safe operating humidity range · Fire: fire potential and survivability · Earthquake: performance and survivability during earthquakes, up to and including Zone 4 as demanded by California · Vibration: performance in the presence of 5 to 100 Hertz (Hz) vibrations · Transportation: ruggedness and durability during transportation · Acoustical: acoustic noise generated · Air Quality: performance in the presence of airborne contaminants, both indoor and outdoor · Illumination: amount of surface reflectance and glare produced GR-1089-CORE, Electromagnetic Compatibility and Electrical Safety - Generic Criteria for Network Telecommunications Equipment, Issue 1, November 1994 The electrical criteria include specifications for: · Electrostatic Discharge (ESD): performance in the presence of ESD · Electromagnetic Interference (EMI): amount of EMI generated by the equipment, as well as performance in the presence of EMI · Lightning and AC Power Faults: performance and survivability during lightning surges and AC power faults · Steady State Power Induction: signalling and supervision functions resistance to induction from the electrical currents and voltages supplied by the facility or outside plant Physical Criteria Electrical Criteria 3 10/97 451 Network Equipment Building System Criteria · Corrosion: prevention of accelerated corrosion, caused by mismatched potentials, in the cables from the outside plant or facility · DC Potential Difference: performance during -3VDC potential differences between the equipment and the facility or outside plant · Electrical Safety: personnel protection from the equipment's operating voltages and currents · Bonding and Grounding: all AC and DC equipment grounding issues, such as multi-point grounding and grounding connectors. Many NEBS criteria are based on national and international standards, and/or Federal Communications Commission (FCC) requirements. However, the NEBS family of requirements is unique in that it addresses issues of personnel safety, protection of property, and operational continuity that are of particular concern to network equip- ment and the environment of telecommunications facilities in the United States. The NEBS criteria are intended to accomplish the following: · Protect personnel from injury · Simplify equipment planning and installation · Protect the network from service outages caused by incompatible equipment · Prevent interference to licensed radio transmitters and cross-aisle equipment · Minimize the risk of fires to network facilities and equipment · Ensure equipment operation under the range of temperature, humidity, vibration, and airborne contamination present in network facilities · Ensure equipment and service survivability in the event of earthquake · Ensure equipment compatibility with the network's electrical environment Bellcore, and most established service providers, feels that compliance with NEBS criteria is critical for network integrity, and NEBS compliance is a major requirement to RBOCs, ILECs, and CLECs who are evaluating the suitability of products for use in their networks. However, assuring NEBS compliance can be a complex matter. Compliance can be affected by the specific nature of the criterion and the intended application of the equipment. Service providers and equipment suppliers have expressed a desire to reduce the time and expense in certifying NEBS compliance. To this end, Bellcore has grouped the NEBS criteria into three functional groups, or levels. This grouping allows the broad range of NEBS requirements to be judiciously applied to equipment based on the its intended application and impact on network operation. NEBS Levels 4 10/97 451 Network Equipment Building System Criteria The minimum acceptable level of environmental compatibility needed to preclude hazards and degradation of the network facility and hazards to personnel. Equipment that may be certified under Level 1 includes prototype equipment for field trials, limited deployment used for non-vital services, and Competitive Access Provider collocated equipment. Conformance to Level 1 does not assure equipment operability or service continuity, however, which are covered in Levels 2 and 3. Level 1 includes the following criteria: GR-63 Physical Protection Criteria · System Fire Test and Material/Components Criteria: fire cause and spread potential and resistivity to fire GR-1089 Electromagnetic Compatibility Criteria · Electrical Safety: personnel protection from existing voltages and currents · Listing Requirements: registration with a nationally-recognized testing laboratory · Bonding And Grounding: types of grounding and grounding connectors · EMI Emissions: containment of radiated electric and magnetic fields for class A and B digital devices, and conducted emissions for all leads · Short Circuit Test: in the event of a short circuit, equipment will not be damaged or become a fire, fragmentation, or electrical safety hazard · Lightning Immunity (Second Level): in the event of a second level lightning surge, equipment will not be damaged or become a fire, fragmentation, or electrical safety hazard · Current Limiting Protector Test: in the event that allowable time-current limits are exceeded, current-limit protectors are required · AC Power Fault Immunity (Second Level): in the event of a second level AC power fault, equipment will not be damaged or become a fire, fragmentation, or electrical safety hazard · Voltage Limiting Protector Test: document any special voltage protection required The minimum acceptable level of environmental compatibility needed to provide limited assurance of equipment operability within the controlled or normal network facility environment. Equipment that may be certified under Level 2 includes equipment deployed in highly-controlled environments such as data centers, and widespread or long-term deployments of equipment performing non-critical network service where loss of equipment operation under environmental extremes can be tolerated. Level 2 includes all the criteria in Level 1 plus all the following criteria: GR-63 Physical Protection Criteria · Operational Thermal (Operating Conditions): a temperature range of 5 to 40 degrees C and a relative humidity range of 10% to 85% · Earthquake (Zone 2 Level): a Zone 2 earthquake is 40% of the Zone 4 intensity and covers 90% of the US · Office Vibrations: low level vibrations in the 5 to 100 Hz range · Airborne Contaminants (Indoors Levels): gases and dust found indoors GR-1089 Electromagnetic Compatibility Criteria · ESD (Normal Operations): proper operation under normal facility ESD levels · EMI Emissions: containment of radiated electrical and magnetic field emissions, and conducted emissions on all power and signal leads · EMI Immunity: proper operation in radiated electrical and magnetic fields, and conducted RF signals on all power and signal leads · Lightning Immunity (First Level): proper operation in the event of a first level lightning surge Level 1 Level 2 5 10/97 451 Network Equipment Building System Criteria · AC Power Fault Immunity (First Level): proper operation of ports in the event of a first level AC power fault · Steady State Power Induction Requirements: proper operation of signaling and supervisory functions during power inductions from the loop and outside plant The minimum acceptable level of environmental compatibility needed to provide maximum assurance of equipment operability within the network facility environment. The Level 3 criteria provide the highest assurance of product operability, and are suited for equipment applications that demand minimal service interruptions over the equipment's life. Equipment that may be certified under Level 3 includes critical network equipment such as digital switches, transport products, and power systems. Level 3 includes all the criteria in Levels 1 and 2, plus all the following criteria: GR-63 Physical Protection Criteria · Operational Thermal (Short-Term Conditions): a temperature range of -5 to 50-55 degrees C and a relative humidity range of 5% to 90% · Storage Environments and Transportation and Handling: requirements for effects of storage in high and low temperatures and high humidity, handling during transporta tion and installation, and transportation vibration · Earthquake (Zone 4 Level): fastening and performance during Zone 4 earthquakes, the highest severity level in the US · Airborne Contaminants (Outdoor Levels): outdoor pollutants and contaminants GR-1089 Electromagnetic Compatibility Criteria · ESD (Installation and Repair): proper operation under ESD that may be experienced during installation and repair · EMI Emissions (Open Doors): radiated electric field emission levels when the cabinet doors are opened or removed · EMI Immunity (Open Doors): ability to withstand radiated electric fields of 10V/m with and without doors/panels · Steady State Power Induction Requirements: proper operation of signaling and supervisory functions during power inductions from the loop and outside plant The criteria that deal with equipment installation and improving the overall equipment environment do not readily fit into the three levels defined above. These criteria may be applied in conjunction with any of the three levels previously described, and may be specific for a given application or for special circumstances. Examples include: GR-63 Physical Protection Criteria · Spatial Requirements: all physical dimensions and space requirements · NEBS-2000 Framework Requirements: physical design of cabinets and frameworks consistent with national and international standards · Altitude: proper operation at altitudes up to 4000 m · Thermal Heat Dissipation: maximum internal and surface temperatures · Acoustic Noise: emitted noise · Illumination: minimum level of illumination required, surface reflectance and glare, and use of energy efficient components Level 3 6 10/97 451 Network Equipment Building System Criteria GR-1089 Electromagnetic Compatibility Criteria · DC Potential Difference: proper operation in the presence of a -3 VDC difference between loop ends · Lightning Surge Characterization: voltage, current and time duration of test generators used to perform the lightning and AC power fault tests · Corrosion: polarity of the network facility battery and magnitude of the applied potential Arranging requirements in this fashion helps simplify and expedite product analyses by focussing on the most critical areas first. Testing to a basic level of environmental requirements expedites equipment deployment without compromising the integrity of the network. This is particularly beneficial to emerging technologies, where rapid deployment is necessary to maintain competitive efficiencies. As products are refined and deployed more widely, manufacturers can then address conformance to the other NEBS levels as required. However, the levels are not implications of relative importance. Bellcore feels that all the NEBS criteria are important for efficient equipment deployment, and reliable and safe operation. The RBOCs and other ILECs are using the NEBS standards to regulate the quality and operability of equipment collocated by CLECs in incumbent facilities. Carriers must now have proof of NEBS compliance before their equipment can be located in any incumbent CO facilities or outside plant. Thus, all service providers - RBOCs, CLECs, and ILECs - are demanding that products be fully NEBS tested and compliant before they will commit to the purchase and installa- tion of this equipment in their network facilities. Manufacturers such as ADC must be able to provide certificates of compliance to the service providers, verifying that their equipment meets the NEBS criteria. In response, more and more manufacturers, including ADC, are implementing the NEBS criteria early in the product design phase, and testing for NEBS compliance during the development cycles to obtain NEBS certification as easily as possible. Designing to meet all applicable NEBS levels from the beginning of the design process provides the fastest product deployment and the most cost-effective network service. ADC's Soneplex ® platform is the lowest total-cost solution for carriers to expand their T1-based business services. As the growth of T1 explodes, the Soneplexr system provides the most efficient and cost-effective method of delivering T1-based services over copper or fiber facilities. The intelligence built into the Soneplexr platform provides integrated management capabilities for improved visibility and troubleshooting. The Soneplex platform accepts a wide variety of transport modules, including High-bit-rate Digital Subscriber Line (HDSL) and standard T1 repeaters, as well as modules for fiber optic lines, thus providing carriers one integrated platform for all T1-based services. This flexibility and integrated network management guarantees carriers the lowest total-cost solution for the entire network, from first cost to provisioning and turn-up, through operations and maintenance. ADC's Approach Impact on Carriers and Suppliers 7 10/97 451 Network Equipment Building System Criteria Issues Concerning Other Existing Equipment Summary and Conclusions Every Soneplex product is designed in full compliance with all NEBS criteria,in mind. At the beginning of the design process for a particular product, a set of "design-to" requirements are specified, including all applicable sections of both GR-63-CORE and GR-1089-CORE, up to and including Level 3 criteria, along with several other docu- mented standards. ADC engineers then incorporate these criteria in the product design as it evolves up to the development stage. Once in the development stage, ADC tests the initial prototypes and final pre-production models using the applicable test methods as specified in the NEBS documents. Over 20 different tests are performed on each and every Soneplexr product. ADC is equipped to conduct many of these tests in-house, while the remainder are conducted by independent third-party testing laboratories, such as Underwriters Laboratories (UL). Full test reports containing all the test data and verification of compliance to NEBS criteria are produced at the completion of these tests. ADC uses these reports as certify- ing documentation to Bellcore to verify that the products meet the applicable NEBS standards, and obtain NEBS compliance certificates in the quickest and most cost- effective manner. ADC customers thus have full NEBS certification documentation for each and every Soneplex product. Service providers are becoming increasingly aware that compliance to NEBS standards can mean faster and more cost-effective deployment of their equipment, especially the new emerging technologies where quick deployment can mean an increased competi- tive edge. However, customers may not be aware that much older and extensively-deployed equipment is not NEBS compliant. Newer products, although certified NEBS compliant by themselves, can be compromised when used with this older equipment. Such an installation must be considered suspect, and should be evaluated and tested for compli- ance as a total system. All Soneplex products have been designed using an integrated systems approach, and are designed in accordance with the NEBS standards from the very beginning. In addition, ADC has also prepared installation procedures for the Soneplexr products so that compliance to NEBS criteria is maintained after the equipment is installed in a network facility. This attention to detail gives customers the choice of a total system that is fully NEBS compliant. To obtain the lowest total cost solutions for the delivery of T1-based services, carriers must look for a supplier capable of understanding the critical details of the problems and issues they face, such as conformance to the NEBS criteria. The RBOCs and other ILECs, as well as newer CLECs, are now requiring full NEBS compliance for all equip- ment that will be installed in their facilities. 451 10/97 Original © 1997 ADC Telecommunications, Inc. All Rights Reserved An Equal Opportunity Employer 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. ADC Telecommunications, Inc. P.O. Box 1101 Minneapolis, Minnesota 55440-1101 FAX: (612) 946-3292 From North America, Call Toll Free: 1-800-366-3891, Ext. 3223 Outside of North America: 612-938-8080 Home Page Address: http://www.adc.com International Sales Offices: Belgium 32-2-712-6500 • United Kingdom 44-734-441955 • Montreal, Quebec (514) 677-9166 • Vancouver, BC (604) 270-1675 • Toronto, Ont. (905) 629-3104 • Ottawa, Ont. (613) 723-2171 • Singapore 65-225-8228 •Venezuela 58- 2-286-1444 • Mexico City, Mexico 525-658-4519 • Buenos Aires, Argentina (541) 449- 2669 • Sao Paulo, Brasil 55-11-3040-0666 • Sydney, Australia 61-2-9975-1499 • Melbourne, Australia 61-3-9585-3931 • Beijing, China 86-10-6500-7001 • Dusseldorf, Germany 49-211-530-6550 Network Equipment Building System Criteria The Soneplex Total Solution ADC's Soneplex system is the lowest total cost solution for carriers to grow their T1- based business services. Focused on providing flexible, end-to-end solutions, the Soneplex system saves carriers money on T1-based services over copper or fiber, using HDSL, ADSL, traditional T1 repeater or Optical DS2 technology, in a single platform. From operations, maintenance, provisioning and high-speed backbone connections to central office space and cabling, the Soneplex system is designed to take costs out of today's T1 delivery approach, adding profit to your bottom line. As a set of physical and electrical specifications developed and released by Bellcore, NEBS guidelines help equipment manufacturers like ADC to focus the product design process on compatibility of their equipment with the physical and environmental conditions that exist within network facilities. Conformance to these criteria ensures personnel safety, property protection, and network operational continuity, as well as help reduce product development, installation, and maintenance costs. All ADC Soneplex products are designed to be fully compliant with all applicable NEBS criteria from the beginning of the design process through final installation in the network facility. ADC certifies full NEBS compliance on every product in the Soneplex family, from modules to mounting, thus providing total system NEBS compliance. Companies that aren't concerned with the total costs of delivering T1-based services won't remain in business for long. ADC's thorough understanding of the issues confront- ing the industry, along with its expertise in systems integration, access technology, transmission systems, physical connectivity, and network management, enables ADC to give carriers the lowest total cost solutions for providing these services. Carriers must look for a supplier capable of understanding the critical details of the problems they face. ADC, in close cooperation and partnership with the carriers, is that supplier. . multi-point grounding and grounding connectors. Many NEBS criteria are based on national and international standards, and/or Federal Communications Commission (FCC). humidity, handling during transporta tion and installation, and transportation vibration · Earthquake (Zone 4 Level): fastening and performance during Zone 4