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When deploys the voice communication at first, SONET/SDH now has been serving the supplier network in the deployment to play the influential role, it the pronunciation, the video frequency and the data has carried on the formidable reliable single transmission mechanism the perfect combination. However, deploys now the numerous equipment constructions are unable to carry on the data demand which fully the expansion will satisfy grows unceasingly in the future. In addition, assumes the exponential growth unceasingly along with the node quantity, disposes and manages these networks becomes day by day complex. In pays great attention the low cost now in the service supplier environment, the telecommunication operator is seeking reduces the fund and the operation disbursement method. They need to carry on the seamless expansion to its existing SONET/SDH infrastructure, with the aim of enhancing the capacity unceasingly, meanwhile can with ease provide and maintain each kind of service. Three kind of key technologies’s enhancements will cause to serve the supplier during retention pronunciation income, but can also with ease carry on to its existing SONET/SDH infrastructure adjusts and expands to take the data as the central future world. First, the new exchange structure technology may may reach 160 G, 320 G, 640 G to existing and the new platform - - capacity as well as higher - - provides seamlessly in the service extendibility (in-service scalability), but does not need fundamentally to change the construction. Second, to broadcasts the service and the more nimble port layout aggregate demand increased the connection to supply software’s complexity unceasingly; The numerous system manufacturers are seeking simplify and strengthen supply software’s method, therefore may enhance the entire network performance. Finally, in the SONET/SDH system’s port card and between the exchange structure’s standard interface will promote ASSP and between the ASIC manufacturer interoperability, enables the system design personnel to increase the use standard interface nimbly the unique service, simultaneously simplifies the system administration. The SONET/SDH exchange system uses in two kind of exchange constructions generally one kind: Single stage or multistage. The use single stage construction will usually found the small unblocking structure (grooming fabric). Speaking of the specific technical type, the single stage construction fixes generally in the band width, if does not climb to the multistage constructions, is unable to carry on the expansion. Because only then an exchange element, therefore this system may with ease carry on the implementation. On the other hand, the multistage structures based on the time, spatial, the time third-level construction, may with ease carry on the expansion generally in the physical limit. Although this method can satisfy the band width the extendibility request, but need more component numbers, higher power, will also increase the software complexity. For example, uses the SONET/SDH system which a structural element designs to be possible to provide 160G the exchange capacity. If expands this structure to 640 G needs 12 such exchange elements (to have in three rows four components). Namely, the exchange structure’s system cost and the power will increase 12 times, but will increase generally only 4 times in the accumulation capacity. Another kind of plan uses the lamination construction. The lamination construction may start from a single element construction to carry on the linear expansion, the component number which thus with its multistage structure obviously reduced the construction to be possible to compare favorably with the large-scale structure which needs. Essentially, the lamination construction may between the single stage many parallel exchange element the profile information way, each element (sub-granular level) dredges the current capacity by the Asian granularity level. For example, in above expansion question, we hoped that will exchange the structure the collection capacity to increase from 160 G to 640 G. Further, if between each line tax office outpost and the structure card has four data links, then we hoped the above situation will realize generally then (each link by 622Mbit/s or the 2488Mbit/s speed movement). In the lamination construction, the line tax office outpost’s each data byte may carry on the expansion in four data links, therefore the first link may the load bearing bit (bits) 1 and the bit 2, the second link may the load bearing bit 3 and the bit 4, ex analogia. In the following time slot’s following byte may the similar way carry on the assignment. Because in each link may lay aside each byte two units places, therefore this is called the two-position lamination. Thus, a four structural element time may two two place exchange data, so that is exporting the line tax office outpost (egress line card) place to carry on assembles. Uses this kind of lamination technology, this construction only through uses four structural elements then to be possible the linear expansion to 640 G, but a third-level non-lamination construction will need 12 at least. Has many important discoveries in this construction. First, each structural element is communicates in the general port/time slot exchange data. Therefore, each exchange element may carry out the same task, but may also share the general matrix disposition. Second, each line tax office outpost must be able to mark through many data interface data, and may export the line tax office outpost group to should again the data. Third, this structural element own must be able to carry on the addressing and the exchange by the sub-granularity level. Although this increased the element own design complexity truly, but the overall volume of goods handled and the byte addressable element are the same, namely only increases the exchange granularity; Two-position lamination element (power and size) the physical property and the byte addressable element are similar. Finally, does not change the foundation construction in the promotion process: Because may the parallel processing data, therefore the entire element group may take the single component. Fast and the nimble service provides In the exchange construction design must solve how one of most major problems prevents blocking. when inputs the port/time slot not the output port/time slot which connects requests, even if port this time available, also will present blocking. In double broadcasts the current capacity extremely ordinary (bicast traffic) (e.g. in view of link application) in the SONET/SDH system, this question is especially serious. And so on broadcast the request which to such as the video frequency the service grew day by day to further intensify this question gravity. The exchange structure blocking performance is divided three kinds: Blocking, may rearrange does not have blocking as well as does not have blocking strictly. In the strict non-blocking structure, may carry on the disposition to all connections, but does not need to consider disposes the connection the order. In may rearrange in the non-blocking structure, certain connections are possibly blocked, but has the possibility to carry on the rearrangement throughout to the existing connection to provide the exchange resources. In the blocking structure, the rearrangement will possibly reduce some blocking question, but will be impossible to solve all possible connections. Speaking of above category’s each kind, the blocking behavior to the specific type’s current capacity is specific. For example, speaking of double broadcasts the current capacity, the structure possibly is may rearrange non-blocking, but regarding broadcast possibly is blocking. In the individual element structure, may with ease solve the blocking problem through the use sharing core memory element. In the memory element, each output port/time slot may simultaneously visit all output port/time slot, therefore it belongs in view of all current capacity form strict non-blocking type. The sharing memory element also has other superiority, namely disposes extremely simply, you only need in view of each output port/time slot disposition source port/time slot then, this enormously reduce software’s complexity. But, just like above discusses, carries on the expansion to the individual element structure to be difficult. In the multistage structures, very difficult to block or the non-blocking performance in reality carries on the confirmation. Even if single structure element oneself belongs to the strict non-blocking type, this also does not need to expand as the whole to this structure. In the past, through the port layout limit, broadcast the limit, the connection rearrangement as well as the internal structure acceleration and so on carries on the perfect union, the SONET/SDH system design personnel founded the practical multistage structure implementation. Along with the latent connection number’s unceasing growth, needs to eliminate this kind of limit based on the data SONET/SDH system. A lamination construction’s important attribute is exchanges the element group whole to be possible to take the individual element. This and the multistage methods are different, if each independent element oneself is a 160G sharing memory element, then this group as the capacity will be the 640G single sharing memory element. The lamination construction has can the single chip memory element the superiority which to the high-capacity, the multi-chip construction expands, simultaneously maintains the disposition the simplicity as well as the single chip design broadcasts the function willfully. This will realize obviously in the software complex aspect saves, simultaneously will also realize is quicker, the more definite supply time. The supply time may reduce to through the microprocessor connection the time which writes down in the new disposition consumes. The standard interface may simplify the system development and the management May divide into the SONET/SDH network element four basic function planes: Data, control, fixed time and expenses. Although majority of mainly applies in the data plane, but when the network element expands to is larger capacity, other function plane must carry on the expansion. For example, the numerous SONET/SDH systems use by based on the single line tax office outpost microprocessor (may the controller combination which with central processor hard connection) is composed. The micro controller may process local disposes with the interrupt processing, and may to the central processor report statistical data and the event. The central processor carries out the disposition management and the exception handling in turn on the network element level. Along with data plane collection capacity’s unceasing increase, also day by day increases to the controller complex demand. Usually, the controller itself lacks the complexity, needs to carry on the expansion. The similar analysis is suitable for SONET/SDH in the expenses DCC byte signal transmission. When port quantity increases, the signal transmitting system’s burden will then aggravate, should need to carry on the redesign. The numerous system design personnel integrate this achievement each function plane to an general connection good opportunity, other function subsystem may share this general connection, is similar to each kind of PC the function subsystem shares one to share the main line to be the same general. This kind of motive hides in the expansion SONET/SDH serial interface or ESSI. ESSI may define uses in the SONET/SDH system’s signal transmission standard, and may control, fixed time and the expenses management integrates in the general physical interface. May define three function levels OIF TDM to 5 level of structure connection (TFI-5) ultra collection ESSI: Frame, transmission and way. The frame level may define like between the SONET/SDH framing and the exchange structure the serial line’s physical operations. Is similar with in SONET/SDH Duan Ceng, the frame level only exists in the physical vertex, for example from framing on transmitting end to exchange element on receiving end. The electrical signal signaling, the framing, Canada harass, the link wrong monitoring and the frame synchronization insert in the frame level. The frame level’s use is provides the reference point physical interoperability for the network element various modules’ between. At present, the ESSI frame level may define by 622.08 Mbit/s and 2488.32 Mbit/s speed movement serial link. The ESSI frame level may be compatible with the widespread serial technology, including CML and LVDS. The ESSI transmission level may define based on between the ESSI byte transparency system’s, and may correspond in system’s STS-N connection directly. The logical level may aim at each client signal to carry on the definition, and may to export the locator/mapping from the entrance locator/mapping expansion. ESSI transmission level’s all modules may the end through the exchange matrix, including the expenses. If uses gives the matrix lamination pattern, then may also carry on the definition in the transmission level to this pattern. This indicated that the transmission level may carry on the definition in many physical links, generally is 2 power powers of exponent. ESSI way level including H1-H3 indicator byte, entire STS-N actual load and related way expenses. In view of the way recognition, the device status and the way condition may carry on the definition to other bytes. May define the ESSI in many expenses byte as the general port, its may use in implementing in view of other function subsystem’s appropriation signal transmission (proprietary signaling). Because visits the ESSI expenses based on the ESSI component permission, therefore (framing and exchange structure) place may withdraw and insert the transmission expenses in the frame level source and the sink. These technology’s application scope including DCC byte’s centralism gathering, processing and the production, or the controller synthesizes channel’s implementation. From the small CPE equipment to large-scale MSPP and DXC, this method was designing and manages the SONET/SDH network element aspect to provide a bigger flexibility, simultaneously retained the standard interface, will permit future expansion. Increases the band width request which unceasingly along with the system capacity caters to grows day by day, uses the lamination memory construction the new exchange technology becomes these systems more economical highly effective. The expansion SONET/SDH serial interface standardization or ESSI will reduce further system’s cost and the complexity, will thus be many function subsystem to concentrate to a physical subsystem. Will use these key technologies the multi-services to supply platform (MSPP) to provide unprecedented in the service extendibility, the dynamic service supply and the higher network manipuility. The new generation will unblock the construction to cause the SONET/SDH system capacity to be possible promotes from small optical fiber turning on and the edge network to the large-scale city territory optical fiber core network, thus simplified the disposition, the management and the protection cut needs |
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