Teleservice segmentation and reassembly 電信業(yè)務(wù)的分段和重組
Segmentation and reassembly 分段和重組子層
Also , to achieving stability , internal speedup is needed . compared to fixed length switch , by supporting variable length packet switch , there is no need for segmentation and reassembly circuits , and no speedup is necessary to support sar . this dissertation first studies variable length packet switch in unbuffered crossbar 另外,變長交換不需要在數(shù)據(jù)交換前和交換后進(jìn)行分割和組合操作,因此在入端口處不需要一個(gè)額外的切割模塊,而在出端口處則不需要一個(gè)額外的組合定長信元的模塊,節(jié)省了存儲(chǔ)器資源以及信元重排序的規(guī)模。
Secondly , the paper describe the principle of atm network , and the function of ' sar " ( segmentation and reassembly ) and the format of packet aal5 , and introduce the basic idea of ipoa , and the design project and implementing of the control chip . later , the paper introduce the logic function and operational principle of packet buffer control chip and prove the feasibity and correctness of the arithmetic . at last the paper introduce crc - 32 arithmetic based on look up and implement it with hardware 接著詳細(xì)論述了核心路由器atm網(wǎng)絡(luò)實(shí)現(xiàn)的原理,包括“ sar ” ( segmentationandreassembly )功能和aal5報(bào)文的格式, ipoa基本思想,以及控制芯片的設(shè)計(jì)方案和實(shí)現(xiàn)途徑等。然后又論述報(bào)文緩存區(qū)控制芯片的工作原理和邏輯功能等,并對(duì)算法的可行性,正確性等進(jìn)行論證。最后介紹了一種基于查表的crc - 32算法的原理及其硬件實(shí)現(xiàn)。
百科解釋
Segmentation and Reassembly refers to the process used to fragment and reassemble variable length packets into fixed length cells so as to allow them to be transported across Asynchronous Transfer Mode networks or other cell based infrastructures. Since ATM's payload is only 48 bytes, nearly every packet from any other protocol has to be processed in this way.