When a threat is observed, one of the most important challenges is to choose the most appropriate and adequate timely decisions in response to the current and near future situation in order to have the least consequences and costs. Making the appropriate and sufficient decisions requires knowing what situations the threat has engendered or may engender. In this paper, we propose a quantitative risk-based method called QR-SACP to calculate and project situational awareness in a network based on threat information sharing. In this method, we investigate a threat from different aspects and evaluate the threat's effects through dependency weight among a network's services. We calculate the definite effect of a threat on a service and the cascading propagation of the threat's definite effect on other dependent services to that service. In addition, we project the probability of a threat propagation or recurrence of the threat in other network services in three ways: procedurally, network connections and similar infrastructure or services. Experimental results demonstrate that the QR-SACP method can calculate and project definite and probable threats' effects across the entire network and reveal more details about the threat's current and near future situations.

翻译：当观察到威胁时，最关键的挑战之一是针对当前及近期态势选择最恰当且充分的及时响应措施，以最小化后果与成本。做出恰当且充分的决策需要了解威胁已造成或可能造成的态势。本文提出一种名为QR-SACP的定量风险方法，通过威胁信息共享来计算与预测网络中的态势感知。该方法从不同维度研究威胁，并通过网络服务间的依赖权重评估威胁的影响。我们计算威胁对某项服务的确定性影响，以及该确定性影响对其他依赖服务的级联传播效应。此外，我们从三个方面预测威胁传播或重现的概率：程序层面、网络连接层面以及相似的基础设施或服务层面。实验结果表明，QR-SACP方法能够计算并预测整个网络中的确定性与潜在威胁影响，并揭示威胁当前及近期态势的更详细细节。