An attack-resistant network is a purpose-built network to survive attacks; by construction, it should be both resilient and secure. Resiliency is the ability to provide alternative communication paths should one path become disrupted due to failures or attacks; while security is the ability to contain and limit the impact of compromises. Interestingly, these two can present conflicting demands. We provide a first formulation of a new class of problems focusing on the engineering of attack-resistant networks. Our model considers both resiliency and security, and uses a notion of blocking probability as a rigorous measure for evaluating different network constructions. We propose several efficient approximation algorithms for computing blocking probability and provide bounds for their errors. Based on these algorithms, we introduce a family of heuristics to guide the construction of optimal attack-resistant networks with minimum blocking probabilities. We also present extensive results to evaluate and demonstrate the near-optimal performance of our heuristics and approximation algorithms.

We consider the problem of resource reservation for networks. Current approaches for resource reservation in integrated service networks adopt an all-or-nothing approach, where partially acquired resources must be released if resources are not available at all routers on the chosen path. Furthermore, under high load, end-systems must retry requests repeatedly leading to inefficient allocation and increased traffic. We propose a new approach called Deferred REServation (DRES) that substantially improves performance (reduces the overall flow rejection probability and increases link utilization) over the all-or-nothing reservation approach. Flow admissibility is increased by deferring requests at routers for a limited period of time until resources are available. Analytical and simulation results confirm the performance benefits of our approach.

Label switched networks have become increasingly attractive to both network providers and customers. By creating aggregate, bandwidth-reserved flows, these networks offer routing flexibility, predictable bandwidth usage, and quality-of-service (QoS) provisioning. This flexibility in routing enables fault-persistent QoS reservations, where connectivity, and allotted bandwidth remains available, even if some links or network nodes fail. The automatic switch-over from a now-defunct path to a new, working path is known as restoration. Restoring bandwidth-guaranteed paths requires allocation of resources on backup paths that will be used in the event of faults. In this paper, we investigate distributed algorithms for routing with backup restoration. Specifically, we propose a new concept of backup load distribution matrix that captures partial network state, greatly reducing the amount of routing information maintained and transmitted while achieving efficient bandwidth usage. We present and simulate two new distributed routing algorithms, which provide significant improvements in rejection rates and provide substantial savings in bandwidth used and call setup time compared to existing algorithms.

The problem of real-time communication over a multiple access network has been well studied in the past. But, there has been no prior work addressing real-time communication over a switched local area network (SLAN), where several LAN segments are connected through a switch. In this paper we propose real-time protocols for the SLAN. The proposed protocols are based on CSMA/CD with deterministic collision resolution and belong to the dynamic planning based category, where an admission test is performed for guaranteeing message transmission. This test is based on the worst case channel access time that can elapse before a particular node can transmit its message. We also compute the worst case buffer requirement at the switch. We study the effectiveness of the proposed protocoIs through extensive simulation studies.