4 research outputs found
Resilience Strategies for Network Challenge Detection, Identification and Remediation
The enormous growth of the Internet and its use in everyday life make it an attractive target for malicious users. As the network becomes more complex and sophisticated it becomes more vulnerable to attack. There is a pressing need for the future internet to be resilient, manageable and secure. Our research is on distributed challenge detection and is part of the EU Resumenet Project (Resilience and Survivability for Future Networking: Framework, Mechanisms and Experimental Evaluation). It aims to make networks more resilient to a wide range of challenges including malicious attacks, misconfiguration, faults, and operational overloads. Resilience means the ability of the network to provide an acceptable level of service in the face of significant challenges; it is a superset of commonly used definitions for survivability, dependability, and fault tolerance. Our proposed resilience strategy could detect a challenge situation by identifying an occurrence and impact in real time, then initiating appropriate remedial action. Action is autonomously taken to continue operations as much as possible and to mitigate the damage, and allowing an acceptable level of service to be maintained. The contribution of our work is the ability to mitigate a challenge as early as possible and rapidly detect its root cause. Also our proposed multi-stage policy based challenge detection system identifies both the existing and unforeseen challenges. This has been studied and demonstrated with an unknown worm attack. Our multi stage approach reduces the computation complexity compared to the traditional single stage, where one particular managed object is responsible for all the functions. The approach we propose in this thesis has the flexibility, scalability, adaptability, reproducibility and extensibility needed to assist in the identification and remediation of many future network challenges
Re-feedback: freedom with accountability for causing congestion in a connectionless internetwork
This dissertation concerns adding resource accountability to a simplex internetwork such as the Internet,
with only necessary but sufficient constraint on freedom. That is, both freedom for applications to evolve
new innovative behaviours while still responding responsibly to congestion; and freedom for network
providers to structure their pricing in any way, including flat pricing.
The big idea on which the research is built is a novel feedback arrangement termed ‘re-feedback’.
A general form is defined, as well as a specific proposal (re-ECN) to alter the Internet protocol so that
self-contained datagrams carry a metric of expected downstream congestion.
Congestion is chosen because of its central economic role as the marginal cost of network usage.
The aim is to ensure Internet resource allocation can be controlled either by local policies or by market
selection (or indeed local lack of any control).
The current Internet architecture is designed to only reveal path congestion to end-points, not networks.
The collective actions of self-interested consumers and providers should drive Internet resource
allocations towards maximisation of total social welfare. But without visibility of a cost-metric, network
operators are violating the architecture to improve their customer’s experience. The resulting fight
against the architecture is destroying the Internet’s simplicity and ability to evolve.
Although accountability with freedom is the goal, the focus is the congestion metric, and whether
an incentive system is possible that assures its integrity as it is passed between parties around the system,
despite proposed attacks motivated by self-interest and malice.
This dissertation defines the protocol and canonical examples of accountability mechanisms. Designs
are all derived from carefully motivated principles. The resulting system is evaluated by analysis
and simulation against the constraints and principles originally set. The mechanisms are proven to be
agnostic to specific transport behaviours, but they could not be made flow-ID-oblivious