基于路由状态因果链的域间路由不稳定溯源检测方法

Interdomain routing instability traceable detection method based on route state causal chain

针对现有域间路由不稳定溯源检测方法中检测时间受限于路由更新时延、溯源信息可能被篡改的问题,提出一种基于路由状态因果链的域间路由不稳定溯源检测方法。通过分析路由状态间存在的因果关系,定义能够刻画路由状态及其转移过程的路由状态变更标识,将其随路由更新传播发布并存储于区块链,从而构建去中心化、防篡改的路由状态因果链;通过分析本地路由状态因果链判断路由不稳定类型,追溯失效链路或策略冲突自治域序列,完成路由不稳定的溯源检测。理论证明了所提方法能够追溯导致收敛时延的失效链路和导致路由振荡的策略冲突自治域序列,并基于软件路由器在经典拓扑中进行验证。实验结果表明,所提方法可在不改变BGP的前提下及时检测策略与拓扑动态变化导致的路由不稳定现象并确定其源头。

To solve the problem of detection time limitation caused by route update delay and the possible tampering of traceability information in existing route instability traceable detection methods,an interdomain routing instability traceable detection method based on route state causal chain was proposed.By analyzing the causal relationship of route states,the route state update token that can describe the route state change and transfer process was defined.Route state update tokens were published and stored in the blockchain during the route update propagation to construct the decentralized and tamper-resistant route state causal chain.By analyzing the route state causal chain,the type of route instability was judged,and the failed links or policy-conflict AS sequences were located to achieve route instability traceable detection.The capability of proposed method to trace the failure link and the policy-conflict AS sequence which could lead to convergence delay and persistent route oscillation respectively was proven theoretically,and validating experiment based on software routers in typical topology was carried out.The experimental results demonstrate that the proposed method can timely detect route instability caused by the dynamic changes of both policy and topology,and determine type and root cause of route instability without modifying BGP.