Sumitomo Electric released a new generation TYPE-81C touch screen optical fiber fusion splicer

On August 1, 2012, Sumitomo Electric Group released a message to say, a new generation of core open type TYPE-81C optical fiber fusion splicer to be put on the market. The machine is adhering to the " under any environment speeding fusion " concept developed, with small, light weight, strong features, TYPE-81C to achieve the most rapid welding process. Touch screen operation and through the Internet to achieve the remote technical support to provide users with a great convenience, the operation is more simple, more flexible service. Sumitomo Electric Group's subsidiary in China - for Asian trade ( Shenzhen) Limited company general manager Masuke Katsuya commented: " TYPE-81C is from a 30 optical fiber fusion splicer manufacturing history of Japan Sumitomo Electric Group to develop a new generation of products. It contains many innovative, compared to the current market of welding machine, simplifies the user and the operator's use. Touch screen TYPE-81C operation is simple, durable design and remote technical support have greatly reduced the user maintenance cost. All of these short welding time and improve environmental performance improvement will make this core open type welding machine to enter a new era. " TYPE-81C has started in July 1, 2012 in the Chinese market sales.

Analysis of the ROADM equipment management software based on SNMP

This paper introduced one kind based on the SNMP protocol for ROADM network management agent software design and implementation of the program, the method can simplify the design and implementation of Agent, such that Agent put more resources on equipment management and real-time task coordination operation. This scheme can also be used for other equipment. 1 Introduction In recent years, IP, data, video and other business to carry out a wide range of rapid consumption of the optical fiber bandwidth, already matched wavelength is gradually occupied, business development presents the dynamic characteristics. WDM system in expanding its scale at the same time, bound to a new generation of WDM system ULH+ROADM transformation. ROADM ( reconfigurable optical add-drop multiplexer ) with its convenient configuration, can change the wavelength resource allocation, can meet the dynamic needs of the business, and according to the need for intermediate the upper and lower nodes of the wavelength number and the specific wavelength, can avoid wavelength blocking and constructing end-to-end virtual wavelength path [1]. ROADM is ASON key nodes. In the metropolitan area network construction, selection of ROADM equipment, not only can reduce operating costs, ensure the business flexible development, to ensure that the required bandwidth, provide transparent, efficient transmission and exchange; can realize flexible networking, in favor of ASON flow control; and for a smooth transition to next generation network ready. The realization of ROADM mainly have two kinds of train of thought, broadcast / selection type and demultiplexing / multiplexing / cross. Broadcast / selection type ROADM equipment by tunable filter and wavelength blocking filter component. The demultiplexing / Cross / multiplex ROADM device usually adopts the wave division multiplexer / demultiplexer, coupled with controllable light switch [2]. With the rapid development of hardware chip and processor, ROADM equipment single disk can have more processing. So you can be a specific task processing in single disc, instead of Agent to realize. Following the presentation of a ROADM device design and realization scheme of network management agent. This program on ROADM equipment performance, alarm, configuration and proprietary commands and other special treatment, simplified in the command processing module and the response frame processing modules. This can make Agent design more concise, focusing on equipment management and real-time task coordination operation, so that the ROADM device can real-time response network management needs and timely reporting of network information, in order to better the performance of the work. The 2SNMP protocol Based on SNMP protocol simple network management framework, because of the popularity of Internet and get rapid promotion, becoming one of the important technology of network management. SNMP is in the process of constant development, now has SNMPv1/v2/v3 in three main versions; in addition, remote network monitoring ( RMON ) appear to make SNMP to the distributed management to stride one stride. The network management of SNMP model includes four key components: Management ( Manager ), agent ( Agent ), management information base ( MIB ) and network management protocol ( SNMP ), as shown in figure 1. Manager running SNMP client ( Client ) program and network application software, will be responsible for network management commands to the Agent, extracted from the MIB management information and receive from the Agent abnormal event report. The Agent running SNMP server ( Server ) program and MIB handling procedures, is responsible for receiving network management command and MIB implementation of related operations, reported the incident. MIB: preservation and tissue from the tube being cyber source abstract management information. SNMP:Manager and Agent exchange between management information communication rules, is generally based on the realization of the TCP/IP. 3 design and implementation of software 3.1ROADM equipment network management SNMP protocol based on ROADM equipment network management model as shown in figure 2. Diagram of network management agent ( Agent ) as the ROADM equipment and station between the bridges, is running in the managed devices ( ROADM ) in the software, implementation of management process management operation, direct the operation of the local management information base on [3]. The ROADM device Agent with response management station command, collection ROADM equipment information, configuration of ROADM equipment, ROADM equipment information and command execution results are sent to the management station, send TRAP to the management station, save the configuration information and other functions. ROADM Agent MPC860 was selected as the running equipment software hardware platform, operating system using VxWorks embedded real-time multitask operating system; the MPC860 and equipment of each disc communication through MPC860 SPI port to achieve. It can realize the real-time monitoring of equipment, good management performance. Design and implementation of 3.2MIB According to SNMP agreement [4], all managed objects are arranged in a tree structure, in the leaf position on the object is the actual managed objects, each practical managed objects representing some managed resources, activities or the related information. Tree structure itself defines an object to the set of logically related method. ROADM Agent ROADM equipment equipment management system information ( equipment name, device type, device manufacturers, device address ), the operation status of equipment ( alarm or normal ), slot ( slot type information, slot boards in information ), single disc basic information ( hardware, software version, version of the manufacturer information ), single wheel running ( alarm or normal ), single disc temperature, port basic information and port running state. ROADM MIB as shown in figure 3. 3.3 software design ( module ) In accordance with the ROADM device Agent to realize the function of Agent software, will be divided into the following several modules, each module to achieve a specific function, with each other through the function interface link. ROADM equipment Agent software module diagram as shown in figure 4. 3.4 the module realization The communication module: This module to establish socket connection, frame to network management request. From the received UDP packet analyzing the sources of information ( network IP address ). And the data in the UDP header pointer to command parsing module. Response message package module can call the function modules to send Trap or response information to the network management. In embedded systems, will generally be 161 port as the receiving station to the management station sends a request and response information to the port, and the 162 port is used to send Trap to the management station. Command parsing module: This module receives the UDP packet data blocks are analytic, remove community field validation information, to ensure that the legitimate operation; finally will parse out operation object and operation parameters to be passed to the command processing module, a command processing module on the operation of the equipment. The command processing module: This module to realize the management station to ROADM device sends the read, write command analysis and transmission. The process is illustrated in figure 5. First receives the command parsing module pass over the operation object and operation parameters. Then the operation object is analyzed by OID, to find the corresponding device properties ( Equipment, Slot, Card attribute attribute attribute or the Port property ). According to the hardware layer protocol device attributes and attribute values are converted into hardware can identify the sixteen hexadecimal number, packaged into a data frame, was sent to the slave communication module. In response to the frame processing module: This module processing from the lower communication module to report information and response analysis of frame, corresponding managed object properties ( OID ) and managed object attribute values, delivered to the response message package module, and through the interface function to update the database. In alarm and important information to send Trap to Manager. Response message package module: This module will receive the managed object attributes and attribute values ( OID ) bound together, packaged into the appropriate PDU ( protocol data unit ) package, plus the community name and version number, transfer to the upper communication module. Configuration module: network management by the Set command, such as response frame returns to Set news, notice the configuration module will be the new configuration data stored in the database. The system to power up, the module is read out from the database last configuration data, through the command processing module to configure. The communication module: This module establishes a two message queues, one for the ROADM device to send data, another from a ROADM device receives the response frame. The realization of interactive information transparent transmission, completed by Agent software and ROADM communication between devices. The 4 ending ROADM in local / metropolitan area network application, caused various equipment manufacturers and operators of the eager attention. Especially the foreign operators on ROADM cast with high enthusiasm, have wanted to use ROADM to upgrade its infrastructure network idea, and prepare for the future deployment of ROADM technology.

The optical module application characteristics and test parameter values

1 Introduction Today, Ethernet technology has become an indispensable for LAN, also can not be replaced by technology. With the popularization of network, the network scale expanding, Ethernet access technology rapid development, the network transmission rate increase, and the network interconnection and next generation network technology applications, Ethernet transmission method, transmission capacity, service quality more and more attention, in which the transmission distance, transmission rate is the Ethernet transmission ability important reflect, is from the traditional LAN Ethernet technology to the metropolitan area network technology and wide area network technology key. However, from a technical point of view, the transmission rate is higher, limited transmission distance is short; from the application demand, the more high speed, more may be used for transmission, the transmission distance is long. Also because of this pair of contradiction, and high-speed Ethernet to the larger campus backbone and metropolitan area application of rapid expansion, the Ethernet standard transmission distance constraints often encounter challenges: why is the standard distance constraints? In order to meet the actual needs can break through the distance? In this paper, based on the optical media of Gigabit Ethernet standards as reference, emphatically from the media access control method, transmission loss, chromatic dispersion of the transmission of Ethernet transmission distance limitation and breakthrough approach. 2 Gigabit Ethernet standard distance limit Since the 1998 June IEEE 802.3z Gigabit Ethernet standard ( about 1000 Base-SX, 1000 Base-LX and 1000 Base-CX interface ) formally adopted since, has passed the IEEE 802.3ab ( about 1000 Base-T interface ) Gigabit Ethernet standard and IEEE 802.3ae ( about 10 GBase-SR, 10 GBase-LR, 10 GBase-ER, 10 GBase-SW, 10 GBase-LW, 10 GBase-EW and 10 GBase-LX4 10 G Ethernet interface ). But on the long distance transmission of Gigabit Ethernet, the main concern is with the fiber medium related Gigabit Ethernet standard -- IEEE 802.3z. According to the IEEE 802.3z standard, the different optical fiber bandwidth corresponding to the wavelength, the maximum transmission distance as shown in table 1. Wherein, wavelength of 850 nm corresponding to 1000 Base-SX, 1310 nm 1000 Base-LX wavelength corresponding. Table 1 Gigabit Ethernet optical fiber types, corresponding to different wavelength of maximum transmission distance Optical fiber type wavelength ( nm ) mode bandwidth ( MHz• km ) maximum transmission distance ( m ) 62.5 μm multimode 850160220 62.5 μm multimode 850200275 50 μm multimode 850400500 50 μm multimode 850500550 62.5 μm multimode 1310500550 50 μm multimode 1 310400/500550 10 μ m single mode 1 310N/A5 000 In Table 1, and the transmission distance limit is closely related to an important parameter is the modal bandwidth, is a section of the fiber can be adopted by the maximum modulation frequency pulse modulation frequency and the length of the fiber product, it is the embodiment of optical fiber transmission of information capacity, mainly embodies the dispersion on optical fiber system transmission rate, transmission distance effects. Table 1 the relevant parameters in the given condition analysis:①using LD light source rather than low rate system that uses LED light source;②considered the different types, different levels of fiber, especially the traditional optical fiber, the optical fiber emerging not listed but it will provide a better performance;③single-mode fiber mode dispersion can be ignored no, the corresponding mode bandwidth value high enough; the maximum transmission distance without relay amplifying means, dispersion compensation of time distance. 3 key factors influence the transmission distance Effects of Ethernet transmission distance of many factors, such as noise, crosstalk, which is the key factors are the main media access control method, signal transmission attenuation and signal transmission dispersion. The following are their principle, effect analysis, improvement measures. 3.1 media access control method for transmission distance Ethernet media access control method for CSMA/CD is to restrict the transmission distance is the most basic factor, it appears with the Ethernet technology, and with the transmission rate limiting distance shorter. The basic idea of CSMA/CD is to say after hearing, when interference when looking for a chance to say, namely, for each node on the same network, sharing the same transmission medium, monitoring the same network segment of the state, and may try to send data, but at the same time there can be only one node can send all data, other nodes can receive the transmitted data, if the node transmits the data signals are confounded by other signals, that have been in conflict, using backoff algorithm for collision avoidance. Typical backoff is truncated binary exponential backoff algorithm ( Truncated Binary Exponential Backoff ): ( 1 ) when sending a first data when there is a conflict, and m=2; ( 2) give time for r time slices, each slice of time equal to network end-to-end round-trip propagation delay, R 0~2m random number; ( 3) n times when there is a conflict, m (=min n, 10); ( 4) n the maximum value is set to 16, exceeded discard data instead of retransmission. In 10 Mbps, 100 Mbps Ethernet, the minimum frame length of 64 bytes, time slice to send 512 bits required for the 1 Gbps Ethernet, delay, minimum frame length is 64 bytes, time slice is to send 4096 bits required delay. The minimum frame length constant is to ensure that the Gigabit Ethernet Compatibility, but based on CSMA/CD, to ensure that conflicts can instant, effective detection, the round-trip distance must be small enough so that the short frame, first in the last one before sending back the entire network, according to the signal transmission speed of 200000 km/s calculation, for 10 Mbps, 100 Mbps and Gigabit Ethernet round-trip distance were 10240 m, 1024 m and 102.4 M. Considering the delay caused by the connectors and other equipment, especially rate to send the short frame shorter time, thereby greatly reducing the collision domain diameter, segment length becomes unacceptable tens of meters. A solution to this problem is in the Ethernet frame is increased after a data phase difference extended field, whose length is equal to the time slice can send bits minus the minimum number of bits of the frame. This also resulted in Gigabit Ethernet transmission efficiency reduction, solution is introduced into the frame of the emergency mechanism, i.e. once successfully sent a frame, the station can not need to compete and continue to send other frames, the maximum burst size is limited to 65536 bits. 3.2 signal attenuation on the transmission distance Signal on the transmission medium, the energy will gradually loss, thus determines the signal in the absence of the relay when the maximum transmission distance. When the signal propagating in the fiber, is transmitted to theL average light power and incident when the average optical power exponentially decreasing, namely P ( L ) =P ( 0) 10 -α L/10, attenuation coefficientαunit is the dB/km. For Gigabit Ethernet, in Table 1, the maximum transmission distance is determined according to the corresponding transmission system loss characteristics, including the fiber loss, insert loss, optical path penalty, transmission power, sensitivity, rich degree. In IEEE802.3z, based on the worst conditions considered, given in the maximum transmission distance when the link power budget, see table 2. The implementation of the project, if the relevant parameters are consistent with the data in Table 2, the standard distance within the application is sure to succeed. In practical engineering, there are often beyond the standard distance application requirements, Table 2 the worst conditions of link power budget Parameters of 850 nm, 62.5 μ m850 nm, 50 μM1, 300 nm, 62.5 μM1, 300 nm, 50 μM1, 300 nm, 10 μ m, SMF Link power budget ( dB ) 7.57.57.57.57.57.57.58.0 Link distance ( m ) 2202755005505505505505 000 Channel insertion loss ( dB ) 2.382.603.373.562.352.352.354.75 Link power price ( dB ) 4.274.294.073.573.485.083.963.27 Minimum average transmit power ( dBm ) -9.5-11.5-11.5-11.5-11.0 Receiver sensitivity ( dBm ) -17-19 Extinction ratio ( dB ) 9 Affluence ( dB ) 0.840.600.050.371.670.071.190.16 Of or based on the cost and other factors to consider, need to adopt the standard distance shorter but low cost plan, therefore, it is necessary to analyze table parameters: (1 ) standard numerical determination of the premise: considering a variety of possible situations, such as different manufacturers, different types of connectors, different manufacturers, different types of optical transmission characteristics vary widely, such as the early optical fiber. ( 2) the standard on the transmission distance of extended leave " backdoor ": if consistent with other standard conditions, beyond the range is acceptable. ( 3) the table parameters: ①link power budget and transceiving equipment: link power budget values for the minimum average transmission power and receiver sensitivity difference, therefore, if the actual sending and receiving devices with different parameter values in the table, as long as the difference with the link power budget requirements, should also be able to meet the actual needs. ②channel insertion loss: including the link section of optical fiber connection loss, line loss. ③link power price with the exception of the link loss related, and link dispersion, noise and the sending end of the extinction ratio and so on, its reason is the waveform distortion resulting receiver sensitivity decline. ④link power budget and rich degree: a segment to be successfully implemented, is to meet the requirement of bit error rate signal transmission, the link power budget should be large enough, or the channel insertion loss and link power price should be small enough, in order to make the system power is rich and non insufficient, should meet: Margin = link power budget - channel insertion loss - link power price > 0 ( 4) : data in the table for further analysis: In Table 1 channel insertion loss value should contain at least two of the connector insertion loss and optical fiber line loss. With MT-RJ joint each on the maximum insertion loss value of 0.75 for dB, two for maximum insertion loss value of 1.5 dB, 62.5μ m if the use of multimode optical fiber in the 850 nm band transmission signal, according to the maximum optical attenuation 3.75 dB/km calculation, the maximum distance is 220 m 0.825 dB loss, so a total of 2.325 dB channel insertion loss, still meet the 2.33 dB channel insertion loss budget. For the commonly used SC, ST and FC models of the connector, the insertion loss is much smaller, with a company of Wuhan product as an example, the insertion loss of single mode::≤ 0.3 dB, multimode:≤ 0.1 dB, even MT-RJ connector, its actual insertion loss: single-mode:≤ 0.7 dB, multimode:≤ 0.45 dB; on the other hand, a new multimode fiber attenuation has also been reduced in 850, NM < 3 dB/km, 1300 nm < 1 dB/km. Thus, a single channel insertion loss value, the actual power budget has quite rich. ②table link power budget for 7.5 dB or 8 dB, the actual equipment to provide greater link power budget, it means that the system can provide farther transmission distance. The 3.3 dispersion on Ethernet transmission distance The dispersion of fiber for optical signals of different frequency components and different patterns of components caused by the different transmission speed, it makes the optical fiber bandwidth is narrowed, thus limiting the optical fiber transmission capacity, but also limits the optical signal without electric relay transmission distance. The dispersion of fiber are the main mode of chromatic dispersion, dispersion and polarization mode dispersion, which in the fiber type, the transmission rate of the system, light source, modulation mode of different systems have different effects on. At a high rate, long distance optical fiber transmission system, dispersion of the system has significant effect on. As for the 10 G Ethernet, if the G.652 single-mode optical fiber ( NDSF ), and the EA modulator, only 1550 nm wavelength, light source for chirped single longitudinal mode laser source, at this time, dispersion limited distance is mainly composed of frequency chirp power price and the chromatic dispersion power, its dispersion limited distance of about 34 km; the same environment for the 2.5 Gb/s system, its corresponding dispersion limited distance of about 600 km

Optical module and optical fiber connector application guide

One, the optical transceiver module definition The optical transceiver module is composed of optoelectronic devices, circuits and optical interface components, optoelectronic device includes transmitting and receiving the two part. Transmitting part is: input a certain rate of the signal through the internal drive chip processing after driving a semiconductor laser ( LD ) or a light emitting diode ( LED ) emitted from corresponding rate modulated optical signal, its interior with automatic optical power control circuit, the output power of the optical signal to maintain the stability of. The receiving part is: a certain rate optical signal input module by the light detecting diode is converted to electrical signals. The preamplifier output corresponding rate signal, the output signal is generally PECL level. At the same time in the input optical power is less than a certain value will output a warning signal. In two, the optical transceiver module classification In accordance with the rate: Ethernet 100Base ( 100m ), 1000Base ( GPA), 10GE Application of SDH 155M, 622M, 2.5G, 10G In accordance with the package : 1× 9, SFF, SFP, GBIC, XENPAK, XFP, a variety of packaging. 1 x 9 package -- welding type optical module, the general speed of not more than thousand, use SC interface The SFF package­-- welding small packaged optical module, the general speed of not more than thousand, use LC interface The GBIC package -- hot pluggable Gigabit interface optical module, using SC interface The SFP package -- hot plugging of small package module, the highest rate of up to 4G, using LC interface The XENPAK package -- Application in Gigabit Ethernet, using SC interface XFP -- 10G optical module package, available in Gigabit Ethernet, SONET and other systems, uses the LC interface According to the laser types: LED, VCSEL, FP LD, DFB LD In accordance with the emission wavelength: 850nm, 1310nm, 1550nm etc. According to the using modes: non hot-plug ( 1 ×9, SFF ), hot pluggable ( GBIC, SFP, XENPAK, XFP ) In three, a fiber optic connector classification and main specifications and parameters Optical fiber connector is in a section of the fiber ends are mounted on the connecting head, mainly for the use of light distribution. According to fiber type: single mode optical fiber connector ( usually G.652 fiber optical fiber diameter: 9um, diameter 125um), multimode optical fiber connector According to the optical fiber connector is connected to the head form: FC, SC, ST, LC, MU, MTRJ and so on, the current commonly used with FC, SC, ST, LC, Type FC -- the earliest by Japan NTT development. External reinforcement using metal sleeve, fastening means for turnbuckles. Test equipment selection of the joint more. Type SC -- from the development of Japanese NTT company molded plug coupling connector. Its shell with molding with a mold made of plastic, glass fiber, is rectangular; pin by precision made of ceramic, metal slotted sleeve coupling sleeve structure. The fastening way adopts plug pin type, does not require rotation. Type LC -- company's design. The outer diameter of the sleeve is 1.25mm, are usually used in FC-SC, ST 2.5mm half casing outside diameter. Improved application of density. According to the optical fiber connector head pin end points: PC, SPC, UPC, APC According to the optical fiber connector: diameterΦ 3,φ2,φ0.9 Optic fiber connector mainly optical properties, mechanical properties, interchangeability, environmental performance and life. The most important of which is the insertion loss and return loss of the two indicators. In 1, the optical module transmission rate: fast, Gigabit Ethernet, 10GE etc. In 2, the optical module transmitting optical power and receiver sensitivity: transmitting optical power refers to the transmitting terminal of the light intensity, receiving sensitivity can detect the intensity of light. Both in dBm as a unit, is the effect of the transmission distance is an important parameter. The optical module can transmit distance mainly by loss and dispersion two limited. Loss limit according to the formula: loss restricted distance = ( transmitting optical power - receiving sensitivity ) / optical fiber attenuation to estimate. Optical fiber attenuation and the actual selection of optical fiber. The general current G.652 fiber can achieve 1310nm band 0.5dB/km, 1550nm band 0.3dB/km even better. 50um multimode optical fiber in 850nm band 4dB/km 1310nm band 2dB/km. For fast, gigabit optical module dispersion Limited far outweigh the loss is limited, can not be considered. In 3, 10GE optical module according to 802.3ae standard, the transmission distance and the selection of optical fiber type, Hikarumo Hikaru performance. 4, saturated optical power values of light module receiving end maximum detectable optical power, generally -3dBm. When the received optical power greater than the saturation power time can also lead to error code generation. So the emission light power laser module without attenuation loopback test error phenomenon will appear. In five, the optical module failure reason The optical module failure for transmitting end and receiving end failure analysis failure, the specific reasons, most often a problem focused on the following several aspects: 1 of light pollution and damage Due to the pollution and damage caused by the optical interface of optical link loss becomes larger, resulting in optical link. The reasons are: A. optical module, light exposure in the environment of light pollution, dust entering; B. use of optical fiber connector end face have pollution, light pollution two optical module; C. pigtail optical connector end face used improperly, surface scratch; D. use inferior optical fiber connector;

Analysis on the development and Prospect of optical fiber communication technology

Abstract: analysis of the development of optical communication technology history and current situation of the development, and the development trends of optical fiber communication technology are prospected. One, the development of optical communication technology and present situation Optical fiber communication is the birth and development of an important history of the telecommunications revolution. Fiber made from theory to technology and today's high speed optical fiber communication only several years. From the overseas development process we can see, nineteen sixties metaphase, developed the best optical fiber loss in more than 400 DB 1966, British Standard Institute of telecommunications Kao and Hockham theoretically predicted fiber loss can be reduced to 20 dB / km below, Japan in 1969 developed the first root communications with fiber loss of 100 dB / km, 1970 Corelle ( Corning ) using the " powder " has won the loss is less than 20 dB / km and 4 dB / km of low loss fiber, 1974 Baer Lab ( Bell ) using a modified chemical vapor deposition of a better performance than the Corelle company's fiber products. By 1979, germanium doped silica fiber in the 1.55 kilometers of the loss has been reduced to 0.2 dB / km, it has very close by Rayleigh scattering is decided by the quartz fiber loss limit theory. At present the domestic optical fiber and cable production overcapacity, oversupply. Special optical fiber for fiber such as FTTH still needs to be imported, but the total amount of domestic production of optical fiber and cable, with the international market price of no difference, the cost could not be lower, is already zero profit, in the international market competitiveness is not strong, export volume is very small. Twenty years of light technology two major development, WDM and PON, the two have been relatively mature. Multi service transmission platform for the development of two aspects, one is more effective carrier Ethernet service, data service, on the other hand, is to the development of business. The status of AS0N is the current system only within the device, or is in the network to achieve a number of functions, but some of the core role has not been reached. Two, the tendency and prospects of optical fiber communication technology At present, in the field of optical communication has several hot topic for the development of very high speed transmission system, large capacity WDM system, optical transmission network technology, a new generation of optical fiber and optical access network technology, IPoverOptical. ( a ) to high speed system development The current 10Gbps system has begun mass equipment network, mainly in North America, in Europe, Japan and Australia have also started a large number of applications. However, the 10Gbps system for optical fiber polarization mode dispersion is more sensitive, and has laid the cable does not necessarily can satisfy the opening and use of the 10Gbps system requirement, need the actual testing, certification before installation of the opening. Its practical outlet steering light multiplexing mode. An optical way has many kinds, but at present only the wavelength division multiplexing ( WDM ) mode in the large-scale commercial stage, while the other is still at the stage of experimental study. ( two) to the large capacity WDM system evolution Using electricity time division multiplexing system expansion potential has been tried, however optical fiber 200nm available bandwidth resources only with utilization rate of less than 1%, there are 99% resources are still to be discovered. If a plurality of transmission wavelength of staggered light signals at the same time the level of optical fiber transmission, can greatly increase the fiber transmission capacity, this is the wave division multiplexing ( WDM ) is the basic train of thought. Based on the WDM application huge benefits and in recent years the major breakthrough on the technology and market driven, wavelength division multiplexing system development is very rapid. The current global actual laying WDM system has more than 3000, and the practical system for maximum capacity has reached 320Gbps ( 2× 16 × 10Gbps ), the United States of America lucent company has announced that it will launch 80 wavelengths of WDM system, the total capacity up to 200Gbps ( 80 × 2.5Gbps ) or 400Gbps ( 40 × 10Gbps ). Laboratory of the highest level have reached 2.6Tbps ( 13 × 20Gbps ). Predict before long in the future, the practical capacity of the system can achieve 1Tbps level. ( three) to realize optical networking The utility of WDM technology in spite of the great transmission capacity, but basically is to point to point communication based system, the flexibility and the reliability is not ideal. If in the light path can also achieve similar SDH circuit in the transplanting function and cross connect function words, will add a new layer of power. According to this one main train of thought, optical networking can realize large capacity optical network and the network scalability, reconstruction, transparency, and allows the network nodes and the continuous increase in business volume, interconnecting any system and different system signal. Because the optical networking has potential huge advantage, the United States and Europe and Japan and other developed countries put a lot of manpower, material resources and financial resources for research, particularly the United States Department of Defense Advanced Research Agency ( DARPA ) has funded a series of optical interconnection project. Optical networking have become SDH electric network after another new development climax of optical communication. The construction of a maximum transparent, highly flexible and large capacity of the national backbone optical network, not only for the future of the national information infrastructure ( NJJ ) to lay a solid foundation, but also to our country first Century the information industry and national economic development and national security has the extremely important strategic sense. ( four ) the development of new generation optical fiber The traditional G.652 single-mode optical fiber in the adaptation of the super high speed long distance transmission network development needs have been exposed to the output does not from the heart of the situation, the development of new fiber has become the development of the next generation network infrastructure is an important component of. At present, in order to adapt to the backbone and man 's different development needs, has appeared two kinds of novel optical fiber, i.e. non zero dispersion ( G.655 fiber ) and percutaneous absorption optical fiber ( all wave fiber ). Among them, all wave fiber will be the future development focus, is also a research hotspot now. In the long run, BPON indisputably will be the future of broadband access technology development direction, but from the current technology development, cost and application needs of the actual situation, its distance is widely used in Telecom Access Network this one ultimate goal will have a longer development process. ( five) IPoverSDH and IpoverOptical In the business of lP based data services is the current world information industry development of the main driving force, which can effectively support JP business has become a new technology can have long-term technical life logo. At present, ATM and SDH were able to support lP, respectively called IPoverATM and IPoverSDH both each has its own merits. But from long-term look, when IP business volume increased gradually, need above 2.4 gigabit per second link capacity, it may eventually leaves out middle layer SDH, IP directly in a light path runs, form is very simple and unified IP network structure ( IPoverOptical ). Three kinds of IP transmission technology will be in the development of the telecommunication network in different periods and different parts of the network to play its due role in history. But from the perspective of the future. IPoverOptical will be the most long-term vitality of the technology. Especially with the IP business has gradually become the dominant business network, the JP business ideal transmission technology will become the future network especially the backbone leading transmission technology. ( six ) to solve the network bottleneck by means of optical access network In recent years, the core part of network happened to turn the world upside down changes, whether the exchange, or transmission have been updated for several generations. Soon, this part of the network will become the digital control and master, software, network integration and intelligent, but on the other hand, the existing access is still dominated by twisted-pair copper ( more than 90%), primitive simulation system. The technology has the tremendous contrast, restricting the further development of the entire network. In order to fundamentally solve this problem, we must vigorously develop the optical access network technology. Because the optical access network has the following advantages: ( 1) reduce the maintenance cost and failure rate; ( 2) cooperate with local network structure, reducing node, expand the coverage; ( 3) make full use of optical fiber has brought about a series of benefits; ( 4) building a transparent optical network, meet the multimedia era.

Unified Communications: computer technology with traditional communication technologies

Unified communication means, the computer technology and traditional communication technology one of the new communication mode, both the integration of computer networks and the traditional communication network in a network platform, telephone, fax, data transmission, audio and video conferencing, call center, instant communication and many other application service. In the fusion of communication, the telephone network ( VoIP ) is one of the key. It is also called the "three networks convergence ". Triple play is a generalized, social view, at this stage, it does not mean that the telecommunication network, computer network and cable television network network physical one, but mainly refers to senior business application integration. The performance of technology convergence, network layer can achieve interoperability, to form a seamless coverage, the business layer of mutual penetration and cross, the application layer tends to use a unified IP protocol, in the operation of mutual competition, mutual cooperation, toward the human to provide diversified, multiple media, personalized service of the same target gradually converge, industry regulation and policy also tends gradually to unity. The big three network through technical transformation, to provide voice, data, image and multimedia communications business. This is the so-called triple play. Convergence, in concept from different angles and levels of analysis, can be related to the technology, business integration, industry, terminal and network fusion fusion fusion. At present, more important is the application of level to each other using an unified communication protocol. Optimization of IP optical network is a new generation telecommunication network based, is what we call the convergence of combination. The rapid development of digital technology and the comprehensive use of, make the call, and image signal data are available through the unified coding transmission and exchange, all operations in the network will become a unified "0 " or " 1 " bit stream. The development of optical communication technology, integrated delivery of various business information to provide the necessary bandwidth and transmission of high quality, become the ideal business platform network. The development of software technology makes the big three network and terminal through software changes, the final support for various user desired characteristics, functions and operations. The most important is the unified TCP/IP protocol widely used, will make all kinds of IP based on different online business can realize the intercommunication. The first human has uniform for the three network can receive the communication protocol, from a technical for the convergence of three networks laid the solid foundation. However, if according to the traditional approach to integration will be a long-term and arduous process, how to bypass the traditional networks to achieve fusion purpose, that is to find the revolution of telecommunication system of the road, we must grasp the development trend of the technology, combined with China's actual situation, to choose our own road of development. Our actual situation is data communication compared with the developed country starts late, the traditional data communication business size, compared with the developed countries, the protocol multi-service burden is much smaller, therefore, can be as soon as possible towards IP based system, using IP optimization in optical cable optical network, broadband IP network construction, the acceleration of China's Internet network development, and make the Chinese traditional communication network coexist for a long time, saving expenses and make full use of the existing cyber source.

In order to transport network transition to full service broadband revolution

Broadband bearer all kinds of information application is becoming the business income of the main point of growth. Consumers hope that through mobile phone, computer and television screen whenever and wherever possible to enjoy every kind of integrated broadband services, namely the " full service broadband ". Due to the fierce competition, the bandwidth of the price is the rapid decline. Therefore, in the full service broadband consumer demand is excited at the same time, the operator facing data traffic growth is far greater than the business income growth of the enormous challenges. In the severe market environment, competitive, operators must reasonable planning, construction and operation of networks, including CAPEX ( by reducing network construction costs ) and OPEX ( network operation cost, total cost of ownership ) network, realize the full service broadband health development. Advance of optical transmission network has become one of the important measures of transition part. Full service broadband 3 changes Full service broadband to the operator brings out the 3 dimension change: First of all, the operator must face huge challenges to the network data throughput. Statistical data shows, the second quarter of 2009, the global mobile data bandwidth usage increased by nearly 30%, among them Asian growth at 36%. This also means that the rapidly increasing transmission bandwidth increased room and site operation cost, energy consumption. Therefore, operators must improve the data throughput per dollar, and ensure the lowest construction and operation cost, optimize the network, reduce the total cost of ownership. Secondly, the operator must be able to pass fixed and wireless network seamlessly provides various services. In fact, a full service broadband business users, hope to be able to seamlessly use fixed access or wireless access, from the Internet access to the same content and services. Once again, IP business, will promote the network leading the change of the type of business, from TDM to IP packet based transformation. IP networks can make the operator management cost is reduced, and effectively improve the quality of service and profit, has become a full service broadband operation foundation. Transmission network transformation Reasonable selection of equipment needs hierarchy Massive data, business integration and network IP based on optical transport network, raised new requirement, this expression is in: transmission technique choice and product definition should be able to effectively reduce the construction cost, and can simplify the maintenance management, reduce the OPEX; transport network must be able to adapt to the broadband services refers to the level of growth, to network transmission capacity expansion; transmission network can adapt to all kinds of business efficient bearing demand for bandwidth is provided, and a fast and flexible service scheduling; transmission network can meet a variety of business on the transport properties and QoS requirements, and efficient service protection and recovery. However, it is emphasized, transport network function is to provide for the long-term (based on month or year ) connection, and can provide for network fault service restoration. Operations of the IP and the " IP network ", does not mean that the network will use the traditional IP technology, does not mean that the transmission network by router network will be replaced, but the means that should choose to suit IP business efficient, economic and delivery methods. For the evolution of networks, different operators face the situation varies, depending on whether both wired and wireless network, it is a monopoly operators or new entrants, and policy control and operator organization structure. Relative to the router technology, studies have shown that: using hierarchical lower equipment networking, each down two layer, network TCO will be reduced by more than 30 times. In the particular port capacity, the lower layer device to replace the upper device network, will save CAPEX 3～ 7 times. However, greater savings from OPEX. This is because, first of all, the low layer network equipment, for the same capacity, the equipment used on the lower chip power requirements, the size of the device is substantially reduced, power consumption and air conditioning costs will be substantially reduced; second, the low layer equipment configuration and management of maintenance easier, so the maintenance staff technology level is low lower cost, maintenance, low layer device simplifies the operating means that configuration errors may occur in smaller, more easy to fault location and service recovery; in addition, the operator on the optical network equipment depreciation rate is less than the routing device. These are MSTP and Ethernet is still attractive factor. In certain circumstances, strengthening the routing node transfer function to reduce the optical transmission equipment investment is of great significance. It is mainly applied in the operation of new entrants to the market or small scale network ( enterprise network ), but when the expansion of network scale, equipment number up to hundreds of thousands, network total cost of ownership will benefit greatly from a reasonable level of equipment selection. To manage IP bearing evolution At present, in the transport network of metropolitan area level, operators are widely deployed SDH/MSTP. The advantage of SDH technology in network management, protection, at the same time with the economy. Based on the SDH MSTP will have a packet service capacity. However, SDH/MSTP VC based particle scheduling, limiting its bearing IP business efficiency, therefore, operators have begun to PTN evolution. However, although some operators have expressed to stop the SDH deployment, but considering the network continued evolution requires PTN and the mature market still remain time, MSTP will be in 3 to 5 years continue to be deployed and used. At the same time WDM system a large number of applications, and to enter into various levels of network deployment. Wave division multiplexing ( WDM ) extended fiber optic capacity, and reduce the optical fiber transmission cost, solve the scarcity of resources, by using the optical amplifier, single wave rate to 10G WDM transmission distance can reach 4000 kilometers. Along with the high-speed router port, 40G technology has been widely deployed; 100G is also actively promote, and is expected to in 2011 after beginning to mature. Most of the current deployed WDM system is a point-to-point network, based on reconfigurable optical add-drop multiplexing system ( ROADM ), WDM network can evolve into a mesh network, as the SDH in the original transmission network evolution process. From polycyclic to mesh can obtain 20%～ 30% cost savings, while the network deployment scenarios are also from long distance backbone network to the core, convergence and access network WDM network evolution, widely deployed that can better serve the router network, but can also network with You Bo wins business functions provide direct services, to achieve the simplified network level, saving TCO. IP business direct upload to WDM network will face networking, protection and maintenance management deficiencies. In view of this, a new generation of WDM system through the comprehensive support G.709 function, to achieve IP network and optical network maintenance and management as well as network protection system organic union, OTN will, to achieve IP network and optical network in transport plane uniform. The ASON/GMPLS control plane with reconfigurable ROADM has wavelength scheduling function can further enhance the business recovery ability and service deployment capability and resource management. Through further integration of ROADM and the introduction of OTN/ packet cross will generate new device type -- Based on packet optical transport platform ( POTP ). POTP capacity in hundreds of G to several T to support the fixed broadband and mobile data services in packet transmission, will play an important role in. In short, full service broadband era, in order to optimize the network life cycle cost, enhance the network control and management, network service oriented network flexibility and robustness will be transport network evolution of overall objectives and requirements, thus transmitting network evolution strategy not only focus on the promotion business processing hierarchy and Realization of IP routing, whereas the need from the point of business development and network continuity starting to develop based on network performance and cost ( TCO ) optimal overall development strategy and plan, to achieve the IP oriented economic, efficient, reliable and flexible transmission network.