Flexible Network Monitoring with FLAME

Increases in scale, complexity, dependency and security for networks have motivated increased automation of activities such as network monitoring. We have employed technology derived from active networking research to develop a series of network monitoring systems, but unlike most previous work, made application needs the priority over infrastructure properties. This choice has produced the following results: (1) the techniques for general infrastructure are both applicable and portable to specific applications such as network monitoring; (2) tradeoffs can benefit our applications while preserving considerable flexibility; and (3) careful engineering allows applications with open architectures to perform competitively with custom-built static implementations. These results are demonstrated via measurements of the lightweight active measurement environment (LAME), its successor, flexible LAME (FLAME), and their application to monitoring for performance and security

Active networking : one view of the past, present, and future

All distributed computing systems face the architectural question of the location (and nature) of programmability in the telecommunications networks, computers, and other peripheral devices comprising them. The perspective of this paper is that network elements should be as programmable as possible, to enable the most flexible distributed computing systems. There has been a persistent confluence among operating systems, programming languages, networking and distributed systems. We demonstrate how these interactions led to what is called active networking , and in the spirit of vox audita perit, littera scripta manet (the spoken word perishes, but the written word remains), include an account of how it was made to happen. Lessons are drawn both from the broader research agenda, and the specific goals pursued in the SwitchWare project. We speculate on likely futures for active networking

Emergence in active networks

Any complex system may potentially exhibit unpredicted and undesirable behaviour as a result of certain combinations of input stimuli. An Active Network, being a communication network in which user requested operations are undertaken in the netwOIk nodes themselves, is a candidate to exhibit such behaviour. For example, resource utilisation will be influenced by the specific combination of activities triggered by the users and may develop undesirable characteristics such as a self-sustaining profile. Conventional simulation tools do not detect such characteristics. This thesis proposes a solution based on a Petri-Net model in which the resource utilisation of the Active Network is abstracted above the link level communication element. It is then suggested that a certain type of Emergence in resource utilisation may manifest itself as Self-Similarity. The Hurst Parameter (H) of the resource utilisation profile for each node in the network can then be used to identify the presence of this characteristic. The RlS Statistic is used to estimate sets of H values for a range of different Active Application scenarios. It is subsequently seen that a self-sustaining resource utilisation profile (termed a "Cascading Effect") occurs when a significant subset of the nodes display high values of H. This thesis takes the view that Emergence in Active Networks is a problem that has to be approached with a global comprehension of the system as opposed to the conventional approach of a piecemeal development of solutions. This view is reinforced by the hypothesis that an Active Network is a Complex System and Emergence is noncomplex self-organisation within it. It proposes that the high-level abstraction of the Active Network forms a view by which global comprehension can be obtained and is used for the detection of anomalous behaviour (Le. Emergence). The key enabler for self-organisation is proposed to be 'the resources' within the Active Network nodes and hence the detection technique was focused on the utilisation characteristics of these.EThOS - Electronic Theses Online ServiceGBUnited Kingdo