基于WDM网络分布式物理层损伤感知数据库

WDM network-based distributed physical layer impairment-aware database

网络向高速率和高容量不断升级,在选路过程中自适应地规避物理层损伤进而实现高质量的传输服务已成为亟待解决的问题,而物理层损伤信息的感知和保留是其中的关键。文章通过分析物理层损伤参数,建立分布式PLID(物理层损伤感知数据库)的信息表征表,借鉴流量工程数据库标准协议,扩展其中的OSPF-TE(基于流量工程开放式最短路径优先算法)协议,定义一个新的Opaque LSA(链路状态通告)类型即PLI-LSA(物理层损伤信息的LSA),实现了PLID的建立和更新。比较数据库不同更新方式的控制开销,发现采用基于阈值的更新方式较合适,可满足不同的服务质量对不同波长信道传输质量的要求。

As networks are constantly upgraded to high speed and high capacity, it has become a problem demanding prompt so- lution to adaptively avoid physical layer impairment in the routing process. To this solution, the perception and retention of the impairment information is the key. This paper sets up an information characterization table for the distributed Physical Layer Impairment-aware Database （PLID） by analyzing the physical-layer impairment parameters, makes reference to the traffic engi- neering database standard protocol and expands the OSPF-TE protocol in it so as to establish and update the PLID. It is found that when the control overheads for different modes of update for the database are compared, threshold-based update is more suitable as it can satisfy the requirements of different QoS for the quality of channel transmissions at different wavelengths.