The study of network vulnerability seeks to identify the critical elements with respect to a variety of measures. Generally speaking, a network is robust if external pertubations do not significantly impair its functionality. In this area, we seek to design methods to identify the critical elements. One measure we study is the vulnerability of network clustering to node failure; another is the vulnerability of Quality of Service (QoS) in a communication network to node and link failures.

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Objectives:
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- Identify critical elements for network infrastructure measurements, such as the degree of network clustering
- Design comprehensive vulnerability measure for communication networks capable of utilizing any QoS metric

**Publications:**

- “Assessing Attack Vulnerability in Networks with Uncertainty,” in Proceedings of the IEEE Int Conference on Computer Communications (INFOCOM), 2015 .
- “Are Communities As Strong As We Think?,” in Proceedings of IEEE/ACM Int Conf on Advances in Social Networks Analysis and Mining (ASONAM), 2014 .
- “Bound and Exact Methods for Assessing Link Vulnerability in Complex Networks,” in Journal of Combinatorial Optimization, 2014 .
- “Network under Joint Node and Link Attacks: Vulnerability Assessment Methods and Analysis,” in IEEE Transactions on Networking, 2014 .
- “Hardness And Approximation of Network Vulnerability,” in Handbook of Combinatorial Optimization, 2013 .
- “On the Discovery of Critical Nodes and Links for Assessing Network Vulnerability,” in IEEE Transactions on Networking, 2012 .
- “On New Approaches of Assessing Network Vulnerability: Hardness and Approximation,” in IEEE Transactions on Networking, 2011 .