optical_network_of_SDH__graduate__thesiss毕业设计论文.doc

本科生毕业设计（论文）AbstractIn recent years, with the development of the information society, the global Internet business showed an explosive growth trend. The implementation of the fiber optical network of SDH is on the basis of the transmission platform of ZTE MP320, it can provide a simulation environment for the entire optic transmission network. This paper studies the technique of SDH network, describes the basic principle of SDH mapping multiplexing, structure of frame, categories of topology, and researches the methods of protection of the optic network. According to the instruction requirement, an optic transmission network with 9 nodes is set up, the services between two nodes are configured through the network with the costs or minimum resources of the network. The system time clock is configured and choose node D as primary clock. Office wire is completed and choose node D as controller of the network. Multiplexing section protection and path protection is finished. After careful design, realized simulations, performance tests show that the synchronous digital hierarchy network is reasonable, it can be used for practical engineering.矚慫润厲钐瘗睞枥庑赖。 Key words: SDH; networks; optical transmission; STM-N; networking; multiplexing; optical interface聞創沟燴鐺險爱氇谴净。Table of ContentsChapter 1 Introduction1残骛楼諍锩瀨濟溆塹籟。1.1 Background1酽锕极額閉镇桧猪訣锥。1.2 Characteristics of SDH network1彈贸摄尔霁毙攬砖卤庑。1.3 Research objectives and significance2謀荞抟箧飆鐸怼类蒋薔。Chapter 2 SDH Principles4厦礴恳蹒骈時盡继價骚。2.1 SDH signal frame structure and multiplexing steps4茕桢广鳓鯡选块网羈泪。2.1.1 SDH signal frame structure4鹅娅尽損鹌惨歷茏鴛賴。2.1.2 SDH multiplexing step6籟丛妈羥为贍偾蛏练淨。2.2 SDH equipment logic function blocks5預頌圣鉉儐歲龈讶骅籴。2.3 The basic network topology6渗釤呛俨匀谔鱉调硯錦。2.4 Self-healing network8铙誅卧泻噦圣骋贶頂廡。Chapter 3 SDH Network Architectures10擁締凤袜备訊顎轮烂蔷。3.1 A point-to-point SDH link10贓熱俣阃歲匱阊邺镓騷。3.2 A SDH Ring Network11坛摶乡囂忏蒌鍥铃氈淚。3.3 Multi-Ring SDH Topology12蜡變黲癟報伥铉锚鈰赘。3.4SDH Ring Protection Mechanisms13買鲷鴯譖昙膚遙闫撷凄。3.5The Ring Protection Architectures13綾镝鯛駕櫬鹕踪韦辚糴。Chapter 4 Realization of Optic Transmission Network18驅踬髏彦浃绥譎饴憂锦。4.1 Network topology18猫虿驢绘燈鮒诛髅貺庑。4.2 Networking realization18锹籁饗迳琐筆襖鸥娅薔。4.2.1 Set up the network nodes19構氽頑黉碩饨荠龈话骛。4.2.2 Installation of the boards in nodes20輒峄陽檉簖疖網儂號泶。4.3 System Clock configurations23尧侧閆繭絳闕绚勵蜆贅。4.4 Office wire configurations26识饒鎂錕缢灩筧嚌俨淒。4.6 Service configuration27凍鈹鋨劳臘锴痫婦胫籴。4.6.1 A to I 2mb/s*10 service configuration27恥諤銪灭萦欢煬鞏鹜錦。4.6.2 The results of services of network30鯊腎鑰诎褳鉀沩懼統庫。4.7 Service protection configuration32硕癘鄴颃诌攆檸攜驤蔹。4.7.1 Service protection from A to B32阌擻輳嬪諫迁择楨秘騖。4.7.1 Service protection results35氬嚕躑竄贸恳彈瀘颔澩。4.8 Multiplexing section protection35釷鹆資贏車贖孙滅獅赘。References39怂阐譜鯪迳導嘯畫長凉。Acknowledgements40谚辞調担鈧谄动禪泻類。Appendix I41嘰觐詿缧铴嗫偽純铪锩。IIIChapter 1 Introduction1.1 BackgroundThe SDH is an international standard that is highly popular and used for its high speed data transfer of the telecommunication and digital signals. This synchronous system has been specially designed in order to provide a simple and flexible network infrastructure. This system has brought a considerable amount of change in the telecommunication networks that were based on the optical fibers as far as performance and cost were concerned.熒绐譏钲鏌觶鷹緇機库。1.2 Characteristics of SDH network SDH has been able to rapidly develop and this is its own characteristics are inseparable, and its specific features are as follows: 鶼渍螻偉阅劍鲰腎邏蘞。(1) SDH transmission systems in the world to have a unified frame structure, digital transmission standard rate and standard optical interface is network interworking system, and therefore has good lateral compatibility, it is fully compatible with the existing PDH, and accommodates a variety of new traffic signals, the formation of a global unified standard digital transmission system and improve the reliability of the network; (different levels of the code arrangement) 纣忧蔣氳頑莶驅藥悯骛。(2) SDH access system flow structure of the payload area of the frame is very regular, and the payload is synchronized with the network , which uses software, a direct high-speed signal can drop out of the low-speed tributary signals to achieve the characteristics of a multiplex overcome PDH plesiochronous multiplexed manner for all the high-speed signal multiplexing gradual decomposition and regeneration process is greatly simplified because the DXC, reducing the back- interface multiplex equipment , improved the service delivery network transparency ;颖刍莖蛺饽亿顿裊赔泷。(3) As a result of the more advanced add-drop multiplexer (ADM), digital cross-connect (DXC), self-healing capabilities and reassembly branch network becomes stronger, with a strong survival. Because SDH frame structure arranged a 5 percent overhead bit signal, it is particularly powerful network management functions , and can be unified into a network management system for automation networks , intelligent, channel utilization and reduce network costs and vascular viability played a positive role;濫驂膽閉驟羥闈詔寢賻。(4) Due to a variety of SDH network topology, the network that it consists of very flexible, it can enhance network monitoring, operation management and auto-configuration capabilities, optimize network performance, but also to network operation and flexible, safe and reliable, so the network is very complete and diverse; 銚銻縵哜鳗鸿锓謎諏涼。(5) SDH transmission and switching performance has free combination of function blocks composed through its family of devices, to achieve a variety of different levels and network topology is very flexible; 挤貼綬电麥结鈺贖哓类。(6) SDH does not belong to a transmission medium which can be used for twisted pair, coaxial cable, but for the transmission of SDH.赔荊紳谘侖驟辽輩袜錈。You need to use high data rate optical fiber. This feature indicates, SDH trunk channels suitable for both, but also for regional channels. For example, Chinas national and provincial trunk cable network is using SDH, and it is also easy to mix compatible with fiber-optic cable network (HFC). 塤礙籟馐决穩賽釙冊庫。(7) SDH is strictly synchronized to ensure that the entire network is stable and reliable, less error, and easy adjustment and multiplexing.裊樣祕廬廂颤谚鍘羋蔺。1.3 Research objectives and significance Over the years, intelligent optical transmission technology has been of concern for the industry, it hopes to build intelligent optical transmission network to solve the problem several aspects of the existing transmission network exist: first, the traditional fast-growing online network is difficult to adapt the data service with unpredictability, dynamic allocation of network bandwidth. Second, the traditional optical transmission network mainly rely on manual configuration of network connections, time-consuming and difficult to adapt to the modern network expansion needs new business. Third, in order to improve the reliability of bearer services, the traditional optical transport networks need to set aside a large amount of spare capacity, reducing the efficiency of the transport network bandwidth usage. 仓嫗盤紲嘱珑詁鍬齊驁。In addition, the traditional way to protect business networks is relatively simple, the lack of advanced protection, restoration and routing functions. Synchronous Digital Hierarchy (SDH) is widely used worldwide metro backbone network, telecommunication network and WAN.绽萬璉轆娛閬蛏鬮绾瀧。SDH transmission system is a combination of high-speed large-capacity optical transmission technology and intelligent network technology. It provides convenient and effective data multiplexing and de multiplexing functions, and can reliably transmit data.骁顾燁鶚巯瀆蕪領鲡赙。Chapter 2 SDH Principles2.1 SDH signal frame structure and multiplexing steps瑣钋濺暧惲锟缟馭篩凉。2.1.1 SDH signal frame structureThe STM-N (Synchronous Transport Module level-1) is the fiber optic network transmission standard. It has a bit rate of 155.52 Mbit/s .Higher levels go up by a factor of 4 at a time: the other currently supported levels are STM-4, STM-16, STM-64 and STM-256. Beyond this we have wavelength-division multiplexing (WDM) commonly used in submarine cabling.鎦诗涇艳损楼紲鯗餳類。Frame structureThe STM-1 frame is the basic transmission format for SDH (Synchronous Digital Hierarchy). A STM-1 frame has a byte-oriented structure with 9 rows and 270 columns of bytes, for a total of 2,430 bytes (9 rows * 270 columns = 2430 bytes). Each byte corresponds to a 64kbit/s channel.栉缏歐锄棗鈕种鵑瑶锬。TOH: Transport Overhead (RSOH + AU4P + MSOH)MSOH: Multiplex Section OverheadRSOH: Regeneration Section OverheadAU4P: AU-4 PointersVC4: Virtual Container-4 payload (POH + VC-4 Data)POH: Path OverheadFrame characteristicsThe STM-1 base frame is structured with the following characteristics:辔烨棟剛殓攬瑤丽阄应。Length: 270 column 9 row = 2430 bytesByte: 1-byte = 64kbit/s speech channelDuration (Frame repetition time): 125 s i.e. 8000 frame/s峴扬斕滾澗辐滠兴渙藺。Rate (Frame capacity): 2430 8 8000 = 155.520 Mbit/s詩叁撻訥烬忧毀厉鋨骜。Payload = 2349bytes 8bits 8000frames/sec = 150.336 Mbit/s则鯤愜韋瘓賈晖园栋泷。Fig. 2.1 Structure of SDH frameSDH frame structure used to carry a block of information , each frame is composed of longitudinal and transverse rows 9 columns 270 N bytes , each byte containing 8bit, the frame structure is divided into a section overhead (Section Overhead, SOH) area , STM- N payload area and snap- pointer (AU PTR) three regional district.胀鏝彈奥秘孫戶孪钇賻。The above method can be obtained when N is an arbitrary value when the rate 14, 16, 64, 256. As can be seen from Figure 1, the entire frame structure is divided into three regions: the section overhead (SOH) to the information payload area and snap pointer. Section overhead (SOH) is the SDH frame structure in order to ensure the normal transmission of information and additional bytes for network operation, management and maintenance of use, its location in the STM-N frame structure is the first 1 9 N columns the first.鳃躋峽祷紉诵帮废掃減。The figure describes basic SDH frame consisting of 9 rows and 90 columns. SDH frame is composed of 810 octets (bytes). Transmission is carried out row wise from left to right and from top to bottom. Bits are transmitted serially.稟虛嬪赈维哜妝扩踴粜。The STS-1 frame of SDH is composed of section overhead, transport overhead, payload overhead and data part. The frame starts with fixed A1/A2 bit pattern of 0xf628 used for bit/octet synchronization. SDH is referred as octet synchronous. The first three columns of SDH frame is referred as transport overhead. The next 87 columns of the frame are referred as Synchronous payload envelope (SPE). Payload overhead is part of SPE.陽簍埡鲑罷規呜旧岿錟。51Fig. 2.2 Section overheadSTS-1 data rate is about 51.84 Mbps. Let us examine how this has been achieved. Every SDH frame repeats once every 125 micro-sec. 90 columns in 9 rows and 8000 times per second and 8 bits per octet give us data rate of 51.84 Mbps. STS is the abbreviation of Synchronous Transport Signal. STS-1 is referred as OC-1(Optical Carrier) after scrambling is done on STS-1.沩氣嘮戇苌鑿鑿槠谔應。2.1.2 SDH multiplexing stepThe multiplexing principles of SDH follow:Mapping - A process used when tributaries are adapted into Virtual Containers (VCs) by adding justification bits and Path Overhead (POH) information.钡嵐縣緱虜荣产涛團蔺。Aligning - This process takes place when a pointer is included in a Tributary Unit (TU) or an Administrative Unit (AU), to allow the first byte of the Virtual Container to be located.懨俠劑鈍触乐鹇烬觶騮。Multiplexing - This process is used when multiple lower-order path layer signals are adapted into a higher-order path signal, or when the higher-order path signals are adapted into a Multiplex Section.謾饱兗争詣繚鮐癞别瀘。Stuffing - SDH has the ability to handle various input tributary rates from PDH. As the tributary signals are multiplexed and aligned, some spare capacity has been designed into the SDH frame to provide enough space for all these various tributary rates. Therefore, at certain points in the multiplexing hierarchy, this space capacity is filled with fixed stuffing bits that carry no information, but are required to fill up the particular frame. 呙铉們欤谦鸪饺竞荡赚。Functions to achieve include; reuse the is a low-cost channel layer multiple signals through the code to make it into the high-speed adjustment channel or multiple high-speed channel layer code signals through the process of adjustment to make it into the multiplex layer. Among them, reuse is reuse roadmap, roadmap ITU-T has a variety of provisions, but a national and regional use only one. Chinas use of SDH signals are multiplexed with the line 10 shown in Figure 2.3.莹谐龌蕲賞组靄绉嚴减。Fig. 2.3. SDH mapping multiplexing principleThe figure on the previous page illustrates the ITU-T SDH multiplexing structure. The notations in the boxes, such as C-1, VC-3, and AU-4, are explained in the table after the figure.麸肃鹏镟轿騍镣缚縟糶。At the lowest level, containers (C) are input to virtual containers (VC). The purpose of this function is to create a uniform VC payload by using bit-stuffing to bring all inputs to a common bit-rate ready for synchronous multiplexing. Various containers (ranging from VC-11 at 1.728 Mbit/s to VC-4 at 139.264 Mbit/s) are covered by the SDH hierarchy. Next, VCs are aligned into tributary units (TUs), where pointer processing operations are implemented.納畴鳗吶鄖禎銣腻鰲锬。These initial functions allow the payload to be multiplexed into TU groups (TUGs). As the figure illustrates, the xN label indicates the multiplexing integer used to multiplex the TUs to the TUGs. The next step is the multiplexing of the TUGs to higher level VCs, and TUG-2 and TUG-3 are multiplexed into VC-3 (ANSI mappings) and VC-4. These VCs are multiplexed with fixed byte-stuffing to form administration units (AUs) which are finally multiplexed into the AU group (AUG). This payload then is multiplexed into the Synchronous Transport Module (STM).風撵鲔貓铁频钙蓟纠庙。The information structure level SDH multiplexing step is called Synchronous Transport Module using STM-N (Synchronous Transport, N = 14, 16, 64), in fourfold module, the basic module STM-1. Four STM-1 synchronous multiplexing constitute STM-4, 16 个 four STM-1 or STM-4 synchronous multiplexing constitute STM-16, the structure shown in Figure 2.4.灭嗳骇諗鋅猎輛觏馊藹。Fig. 2.4 Structure of SDH synchronous multiplexingSDH transmission network is composed of different types of network elements connected via fiber-optic cables composed of different network element SDH network to complete the transfer function: up / down operations, cross-connect services, such as self-healing network failure.铹鸝饷飾镡閌赀诨癱骝。TM - Terminal Multiplexer Terminal: terminal multiplexer used on the site of the network, such as the two endpoints of a chain which is a dual-port device, shown in Fig. 2.5.攙閿频嵘陣澇諗谴隴泸。Fig. 2.5 Terminal MultiplexerADM - Add / Drop Multiplexer: add / drop multiplexer for SDH transmission network adapter at the site, such as the chain of intermediate nodes, or SDH node on the ring is the most used online, the most important one network element, which is a three-port device, as shown in Figure 2.6.趕輾雏纨颗锊讨跃满賺。Fig.2.6 Add/drop multiplexerREG - regenerative repeater: optical transmission network, there are two regenerative repeater, and a purely optical regenerative repeater, the main power amplifier to extend the optical distance of the optical transmission; other is for pulse regeneration shaping the electric regenerative repeater, mainly through the optical / electrical conversion, sampling the electrical signal, reproduction judgment plastic, electrical / optical conversion, line noise does not accumulate in order to achieve and ensure transfer of the signal waveform on line integrity. After talking here is a regenerative repeater, REG is a two-port device, only two line ports - W, E, shown in Figure2.7.夹覡闾辁駁档驀迁锬減。Fig.2.7 Regenerative repeaterDXC - digital cross-connect equipment: digital cross-connect equipment to complete the main cross-connect function STM-N signal, it is a multi-port device, it is actually equivalent to a cross-matrix, to complete the cross-connect between the various signals, such as Figure 2.8.视絀镘鸸鲚鐘脑钧欖粝。Fig.2.8 Digital cross-connect equipment2.2 SDH equipment logic function blocksSDH equipment logic function blocks is shown as figure 2.9.偽澀锟攢鴛擋緬铹鈞錠。SPI: SDH physical interface TTF: transfer terminal functions RST: regenerator section termination HOI: high-level interfaces MST: multiplex section termination LOI: low-level interfaces MSP: MSP HOA: high-level assembler MSA: multiplex section adaptation HPC: high-end channel connection PPI: PDH Physical Interface OHA: overhead access function LPA: low-level channel adapter SEMF: synchronous equipment management function LPT: lower-order channel terminal MCF: messaging feature LPC: low-level channel connection SETS: Synchronous Equipment Clock Source HPA: high-end channel adapter SETPI: Synchronous Equipment Timing Physical Interface 緦徑铫膾龋轿级镗挢廟。HPT: higher-order channel terminalFig. 2.9 SDH equipment logic function blocks2.3 The basic network topology SDH network element SDH network is interconnected via optical cable from the device, the network node (NE) and the geometric arrangement of the transmission line on the configuration of the network topology. The effectiveness of the network (channel utilization) reliability and economy is largely related to its topology. The basic 騅憑钶銘侥张礫阵轸蔼。 Fig. 2.10 basic network topologyLinear structure: To make the point between two adjacent non- connection function can be realized, which requires that all points should have the connection. This is an economical topology. Intermediate points should be used (ADM) drop multiplexer, both ends of the first and last use (TM) terminal multiplexers. Chain -l