最大缓存时间限制、时延粒度限制、光分组长度限制3大限制因素,对传统光缓存器的前馈型和反馈型两种结构进行了分析。分析表明,影响光缓存器性能的3大限制因素在两种结构中的相互制约关系限制了光缓存器性能的进一步提高。在此基础上提出的一种自适应弹性环光缓存器(E-FLOB)结合了两种传统结构的优势,并分离了3大限制因素间的相互制约关系。结构分析显示,E-FLOB在缓存级数为16时可减少反馈型光缓存器噪声积累约3个数量级。网络性能仿真表明,弹性环结构比前馈型结构使用更少的缓存级数,获得比两种传统结构更低的分组丢失率。
Two traditional types of optical buffers,the feed-forward(FF) type and the feed-back(FB) type,are analyzed based on the maximum buffering time restriction,the delay granularity restriction,and the packet length limitation,which affect the optical buffer performance.Analysis results demonstrate that these limitations restrict each other and prevent the optical buffer performance from being further improved.An adaptive elastic fiber loop optical buffer(E-FLOB) is put forward,which has merits of both FF and FB buffers and decouples the restrictions.Structural analyses show that ASE noise accumulation can be reduced by three orders of magnitude using 16-buffering-stage E-FLOB.Network simulations indicate that the E-FLOB can achieve lower packet loss possibility than both FF and FB buffers with fewer buffering stages than FF buffer.