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Date Submitted Fri. Aug. 2nd, 2013 7:32 AM
Revision 1
Syntax Master claireling
Tags 5e | cable | Category | fiber | optic | optical | splitter
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Fiber To The X (FTTx) is different from a traditional fiber optic network that would be used for a local area network (LAN) application. In most FTTX applications, only one optical fiber is used. That single optical fiber passes data in both directions. This is very different from a LAN application where the transmit optical fiber sends data in one direction and the receive optical fiber sends data in the other direction. In a LAN application, both optical fibers can have data passing through them at the same time.
In an FTTX single optical fiber application, full-duplex operation is typically not possible; Usually only half-duplex operation takes place. This means that part of the time the optical fiber is carrying a signal in one direction, and the rest of the time, it is carrying a signal in the other direction.
FTTx systems typically use multiple wavelengths. The downstream laser is always a different wavelength than the upstream laser. The downstream is typically the longer wavelength, such as 1480nm or 1550nm (or both), and the upstream laser is typically 1310nm.

FTTX is possible with optical fiber distances up to 20km because optical fiber is capable of transmitting information with a very low level of loss. The typical loss for an FTTX optical fiberat 1550nm is 0.25dB/km and 0.35dB/km at 1310nm.

Figure 1 A schematic illustrating how FTTX architectures vary ¡ª with regard to the distance between the optical fiber and the end-user
Fiber To the Home
A fiber-to-the-home (FTTH) PON uses optical fiber from the central office to the home; At the home, a converter box changes the optical signal from the optical fiber into electrical signals. Theconverter box interfaces with existing home cabling such as coaxial cabing for cable TV, twisted-pair cabling for telephone, and Category 5e or 6 cabling for Internet connectivity.
Fiber to the Building
A fiber-to-the-building (FTTB) PON is very similar to an FTTH PON. It uses optical fiber from the central office to the building and there are no electronics helping with transmission in between. The ptical signal from optical fiber is converter into electrical signals in a converter box at the building. The converter box interfaces with existing cabling such as coaxial cabling for cable TV, twisted-pair cabling for telephone, and Category 5e or 6 cabling for Internet connectivity.
Fiber optic setups enable higher speeds of delivery and greater bandwidth than some other kinds of infrastructure. Some of the fiber networks deploying signals to the most sophisticated equipment can benefit from a multimode fiber connection, where a specific kind of fiber optic cable may be used for optimal speed.
Fiber to the Curb
"Fiber to the curb" (FTTC) refers to the installation and use of Fiber Optics Cable directly to the curbs near homes or any business environment as a replacement for "plain old telephone service" (POTS). In a fiber-to-the-curb PON, optical fiber runs from the central office and stops at the curb. The "curb" may be right in front of the house or some distance down the block. The converter box is located where the optical fiber stops, and it changes the optical signal from the optical fiber into electrical signals. These electrical signals are usually brought into the home through the existing copper cabling. The electrical signal may need to be processed by another converter in interface with existing twisted pair cabling for phone, and cat 5e or 6 cabling for Internet connectivity.
Fiber to the Node
Fiber to the node (FTTN) is sometimes referred to as fiber to the neighborhood. A FTTN PON only has optical fiber from the central office to the node. The node is typically telecommunications cabinet that serves a neighborhood or section of a neighborhood. The optical signal from the optical fiber is converted into electrical signals inside the telecommunications cabinet. These electrical signals are distributed throughout the neighborhood through existing copper cables to the houses.
One of the main benefits of fiber to the node and similar systems is the ability to deliver data over more efficient fiber optic lines, rather than other lines with greater speed restrictions. The remaining area from the node to an individual destination, often called "last mile" service, can be achieved with copper or other types of wire. FTTN systems often use coaxial or twisted-pair cable in order to achieve delivery to multiple customers.
The Major Outside Plant Components for an FTTX PON
The outside plant components make up the PON infrastructure and are all designed for installation exterior to buildings. The cables connect different access points in the PON. Everything is initiated from the central office or central switching point.
* Cables
There are feeder, distribution, and drop cables are employed in an FTTX PON.
Feeder cables: Feeder cables run from the central switching point to the local convergence point. These cables typically contain multiple ribbons of 12 single mode optical fibers each. A common feeder cable will contain 18 ribbons for a total of 216 single mode optical fibers.
Distribution cable: Distribution cables run from the local convergence point to the network access point. A distribution cable can have as few as 12 optical fibers or as many as 144. A typical distribution cable has 72 optical fibers.

Drop Cables: A drop cable is a single optical fiber cable that is terminated at the factory, typically with SC connectors on both ends. The cable is environmentally sealed and the connectors are sealed when they are mated.

Figure 2 shows sc connector
* Local Convergence Point

The local convergence point (LCP) is the access point where the feeder cables are broken out into multiple distribution cables. Depending on the architecture of the PON, the local convergence point may or may not be the place where the optical signals are split. The optical signals may be split at the network access point with a Fiber Optic Splitter like the one shown in Figure.

Figure 3 shows optical fiber field rated local convergence cabinet

Figure 4 shows optical splitter
* Network Access Point
The network access point (NAP) is located close to the homes or buildings it services. This is the point where a distribution cable is broken out into multiple drop cables. The NAP is a terminal that serves as a connection point for drop cables. The NAP is a terminal that serves as a connection point for drop cables. It may be installed in an aerial installation, in a pedestal, or in a hand hole.
* Network Interface Device
The drop cable runs from the NAP to the network interface device (NID). The NID is typically mounted to the outside of the house or building. It is an all-plastic enclosure designed to housethe electronics that support the network. The SC connector on the end of the drop cable mateswith the connector in the NID.
0
Date Submitted Fri. Jul. 26th, 2013 4:16 AM
Revision 1
Syntax Master claireling
Tags 6 | cable | Category | fiber | optic | outdoor | products
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Introduction
With the spread of computer applications, along with the rapid development of network technology, the campus network has become an essential school information infrastructure. The implementation of the campus network, for schools to adapt to new developments and make fuller use of existing teaching resources for teching, management has provided a guarantee. Construction of intelligent building network as the physical basis. Using a variety of transmission media of the communication management device and the terminal connected. Its performance can affect the normal operation of the network and the length of life. Therefore, the design of a scientific and rational, optimized campus cabling system is to further play a variety of network equipment functions, the information and communication technologies to achieve the school a good development, improve the level of application management key.
The Campus Cabling System Overview
According to GB/T 50314 "Intelligent Building Design Standards" about the demarcation of ten categories of building regulations, school buildings, including ordinary full-time colleges and universities, high schools and senior vocational schools, junior and primary schools, nurseries and kindergartens school buildings, etc. Different levels of the school, its size, environment, personnel are different, so the campus cabling system requirements will be different.
The Campus Cabling System Features
In China, a full time ordinary institutions of higher learning, the campus area (not including campuses district), in general, nearly acres, some even a few acres. Distribution of number of buildings on campus and many species has a teaching building, comprehensive building, laboratory buildings, art building (including the campus theater, dance halls on campus, campus cultural centers), libraries, teachers' apartments, student apartments, gymnasium, conference centers, schools' hospitals, canteens and so on. Their application also includes teaching, testing, physical, network, accommodation, living, health care and other aspects. For colleges and universities this area, building scattered places different functions in the design of cabling, to be able to meet all of these different buildings, different application requirements, we need the entire cabling system to conduct a comprehensive in depth design considerations.
Figure 1: Campus network design

On campus cabling system, according to the classification of schools located in differnet, differnet mission, teaching different functions, as well as regional and other characteristics of different regions, each school has a different more or less cabling place. However, there are several points which can be used as colleges campus cabling system to explore the commonalities, but also can be used as a variety of colleges and universities can learn from campus cabling system solutions.
1. Campus Cabling diversity
a. Building diversity
We also mentioned earlier, in the campus, especially college a wide variety of buildings, each building its building types and architectural features may vary. Some twenty or thirty or more layers of tall buildings (such as the school's main building, complex building, etc.), while others are one, two dwarf room (such as canteens, etc.); Some large bay, less information building (such as school gymnasium, etc.); While others are small spaces, intensive information construction (such as multimedia classrooms or computer training room, etc.). For such floor height varies, of various sizes, the number of different information points, we have to make different plans. For high rise buildings, for the convenience and savings trunk cable laying wires, equipment room locationi will need to be carefully considered, such as computer room location is set to the middle of the building. And you do not need low building special consideration. For information point-intensive construction, telecommunications room on each floor of its location also needs attention. Because if you set reasonable, we can save a lot of horizontal cable; What's more, if too much information points in the same layer, also need to consider setting up multiple telecommunications rooms. For large bays place, not only to consider the distribution of information points, but also consider wheter there is the level of information points length over 90 meters, if there are more than 90 meters of the situation, we need to consider the use of fiber optic cable or increase between telecommunications solutions. Also, in some campus gymnasium, auditorium and other places, also need to consider whether to set CP boxes and other issues.
b. Application of diversity
In colleges and universities, the diversity of buildings, each building determines the variety of applications. Such as teachers' apartments, student dormitories, school comprehensive building, administration building, a variety of different teaching building, laboratory building used for research, data storage and computing centers. Applications and their information needs are very different. So many applications need not buildings and places, they must be designed according to different requirements. Teachers apartments, student dormitories according to ordinary residential buildings can be cabling design; househole classroom or every student dormitory apartment, basically meet a data point, a voice can be. Comprehensive building, administration building can be carried out according to the way commercial office planning and design; In addition to meet the demand of each office's basic data, voice, consider increasing the internal campus network information in a specific department, such as education private network information point requirements. A variety of conferentce rooms, reception and other areas, need to consider adding wireless AP points. Data storage and computing centers can be designed according to the data center, to meet a variety of information throughout the campus switching, aggregation and storage. The experimental and research laboratory building as an important place, which may have strong radiation, corrosive material existence, there may exist high temperature, humidity, shock and vibration environments, there may be the most dangerous biological virus. Therefore, their application and requirements may be much more than we usually say ten categories of construction areas, so for special programs. To take into account not only the electromagnetic interference, environmental impact, but also consider the potential life safety issues. Therefore, these sites suggest using the whole screen or fiber class industrial grade high flame retardant wiring products, such as using fire-retardant grade reach CMP / OFNP grade, industrial grade reaches IP67 cabling products.
2. High-speed transmission of information
High speed transmission of information for campus cabling system is already a pressing task. A variety of multimedia transmission, video transmission and other large flow of data communication more and more. For school on the high speed network transmission channel is essential. Including multimedia educational system, remote network education system, digital libraries, data centers and other places, is information is very concentrated, at least to ensure Gigabit to the desktop, Gigabit backbone. Under the condition of the budget allows, it is best able to do Gigabit to the desktop, 40G/100G as the backbone for future development needs. For classroom apartment or student residence, it should try to make Gigabit to the desktop requirements. Because who knows, in the next 5-10 years, or longer period of time, how fast development of the Internet? telematics what would happen to the great changes? Campus Network what will change? So in product planning, to do not only meet the existing information and communication needs, but also to do with a certain forward looking.
3. Stability and security of information
In the campus network, the reliability and security of information transmission is very important, because it not only directly related to the use of campus communications network, but also to the entire campus of internal and external education system problems. Which may affect the security of network communications to the national education system. Instability in the event of information or information leaks, not only caused the affected education, and may bring significant social problems. Such as school entrance examination system due to system instability problems, or important information or test data within the education sector was stolen during transmission and so on. So campus intranet for information requirement is in any case have to ensure that the information transmitted high reliability, high security. In the planning and design of the campus cabling must be to choose a good quality cabling products, but also in fiber optic cabling system to avoid interference or disclosure of information. Achieve stable performance, reliable transmission of information security.
The Campus Cabling System Considerations
1. Disaster preparedness
Disaster prevention, for any cabling system is need, and also is necessary. On campus cabling system, pay attention to disaster prevention and many, such as earthquakes, lightning, flood, fire, etc. Around the school to the actual situation may have different, but in the integrated wiring system, the following two disasters have a very important relationship.
a. Lightning Stroke
Campus cabling system is different from general cabling system is one of the local architecture is numerous, wide distribution. Each building and interconnection of information between, or the information architecture and data center interconnection, must pass a variety of outdoor communication cables, so the campus backbone cable corresponding increase, which gives the outdoor cabling lightning protection challenges. Because once a root trunk cable struck by lightning, and the grounding system in case of a problem or did not do, when hundreds of thousands of volts high voltage transient will pass along the cables between devices, resulting in equipment damage, data lost, resulting in significant losses. So into the line of good grounding system and surge protection is very important. Of course, if you want to achieve more secure, avoid outdoor cables in danger of being struck by lightning can also be used outdoors in all non-metallic reinforcing Outdoor Optical Fiber Cable.
b. Fire Disaster
In addition to natural disasters, the current fire casualties and property loss is caused by the most serious disasters. On campus, most of the buildings are crowded places. In addition to selecting a variety of fire related materials and good fire prevention measures, cabling system cables fire retardant also has become essential. Because as the demand for information transmission, communications cable in the building has more than the number of number of strong electric cables trend, but the communication cable fire retardant has not been given due attention.
In addition, for campus cabling system, others, such as the computer room of the need to guard against seismic reinforcement, cables rat bite, etc., also need to pay attention.
2. Management
For school cabling systems, too much applications, and wide distribution of information points, application and needs vary, which brought the system management and maintenance of a great test. The traditional label drawing and handwriting management, or use the computer for documentation and preservation of the way, for such a large cabling systems, it has become beyond their grasp. In particular, to achieve a change to the information point and preservation of records in a timely manner, it is very difficult. Therefore, within the scope of the budget allows, it is recommended universities such as large scale cabling system uses intelligent infrastructure management system to improve cabling system maintenance and management, and enhance network security.
3. Intelligent Building digitized
In campus intelligent cabling, in addition to our previously mentioned, but also includes the campus radio systems, fire alarm systems, electronic fence system, monitoring system, LED large screen display systems, etc. These systems are in the transition to digital. Because of a digital campus will be teaching, research, management, technical services, services life and campus information collection, processing, integration, storage, transmission and application, so that the use of digital resources are fully optimized. By implementing from the environment (including equipment, classrooms, etc.), resources (such as books, handouts, courseware, etc.) to the application (including teaching, learning, management, service, office, etc.) all digitized, in the traditional campus built on a digital space to improve the operating efficiency of the traditional campus, expanding the traditional campus business functions, and ultimately the overall educational process information, so as to improve the management level and efficiency. Therefore, the campus all variety of intelligent system based on transmission channel will also jumped to Gigabit, and even Gigabit network requirements. In the design and planning, and perhaps to consider the application of digitization. In which the product can be selected copper Cat6 Patch Cord, cat 6a, cat 7 products, fiber optic cable in OM4 Cable and other fiber optic products. However, for fire alarm systems, campus broadcasting system, and its products should be chosen to meet the high flame retardant properties, if possible, it is best to choose a high fire retardant cables. Because it does not lead to a fire occurs due to the rapid combustion of the cable causes the system to malfunction.
Figure 2: 305m Bulk Cat6 550MHz Cable UTP

Conclusion
Campus cabling system though complex, but as long as we grasp the core features of cabling system, clear the standard cabling system the basic requirements, specifically the various buildings, the application of the various systems and functions. It is not difficult to design and planning. Even the school have dozens, hundreds buildings, even if there are many school of information and communication applications, the final analysis are inseparable from the basic principles of cabling. Therefore, cabling system in the school, in order to maximize long as we grasp little less to more of the principles from the point to the line, from a line to a plane unfold. You will find, and then a big projects, the final show in front of us or our common and often do a single type of building cabling system, just follow their individual needs and applications for planning and design, you can complete set of perfect school cabling system.
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Date Submitted Thu. Feb. 22nd, 2007 4:14 PM
Revision 1
Helper BerndSchiffer
Tags Category | Inlinetest | RegExp | SwingBuilder
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Ein Kilometerfresser mit Groovy Console, Inlinetests, Groovy Beans, der Meta-Objekt-Programmierung, Swing, GStrings, Regulären Ausdrücken und Closures gebaut. Läuft mit Groovy 1.0 in der Groovy Console.

A Mile-Eater build with Groovy Console, inline tests, Groovy Beans, Meta-Object-Programming, Swing, GStrings, regular expressions und closures. Runs with Groovy 1.0 in the Groovy Console.