Approved for public release; distribution is unlimited / This research concerns information security and computer-network defense. It addresses how to handle the information of log files and intrusion-detection systems to recognize when a system is under attack. But the goal is not the usual one of denying access to the attacker but providing a justification for deceptive actions to fool the attacker. We implemented a simple demonstration of how two different kinds of open-source intrusion-detection systems can efficiently pool data for this purpose. / Lieutenant Commander, Brazilian Navy

Approved for public release; distribution in unlimited. / Contemporary large-scale networked systems have improved the efficiency and effectiveness of our way of life. However, such benefit is accompanied by elevated risks of intrusion and compromises. Incorporating survivability capabilities into systems is one of the ways to mitigate these risks. The Server Agent-based Active network Management (SAAM) project was initiated as part of the next generation Internet project to address the increasing multi-media Internet service demands. Its objective is to provide a consistent and dedicated quality of service to the users. SAAM monitors the network traffic conditions in a region and responds to routing requests from the routers in that region with optimal routes. Mobility has been incorporated to SAAM server to prevent a single point of failure from bringing down the entire SAAM server and its service. With mobility, it is very important to select a good SAAM server locality from the client's point of view. The choice of the server must be a node where connection to the client is most survivable. In order to do that, a general metric is defined to measure the connection survivability of each of the potential server hosts. However, due to the complexity of the network, the computation of the metric becomes very complex too. This thesis develops heuristic solutions of polynomial complexity to find the hosting server node. In doing so, it minimizes the time and computer power required. / Defence Science & Technology Agency (Singapore)

Approved for public release; distribution is unlimited. / Wireless networks can be broadly classified into two types - infrastructure based networks and ad hoc networks. The former uses fixed base stations (infrastructure) which are responsible for coordinating communication between the mobile hosts (nodes). These base stations are interconnected by wired back bones, where as mobile nodes communicate with the base station through the wireless media. The latter one consists of mobile nodes which communicate with each other through wireless medium without any fixed infrastructure. Hence there is no centralized infrastructure that takes care of the routing of information among the participants in the network. There has been a growing interest in ad hoc network in recent years as mobile devices have become more powerful and are capable of processing data like their desktop counterparts. When such a capability is available these devices should be able to share information among them without reliance on existing network infrastructure. Mobile devices are self configurable into either infrastructure or ad hoc mode. Protocols and software have been developed to enable mobile devices to connect to an infrastructure node, where as the same is not the case in the ad hoc environment. Host mobility causes frequent and unpredictable topological changes in a wireless environment. Finding and maintaining routes in ad hoc networks is a non trivial task. This thesis will develop collaborative services in an ad hoc (802.11) wireless environment. / Major, Indian Air Force

Call number: LD2668 .T4 1986 M67 / Master of Science / Computing and Information Sciences

M.B.A. / Electronic Data Systems (EDS) Africa is part of EDS International, one of the largest outsourcing companies in the world. EDS's clients expect EDS to have the required knowledge and decision-making skills to ensure that their Wide area NETWORK (WAN) redundancy is in line with the business requirement. This is a careful balance between spending money on redundancy compared with the cost of WAN downtime to the business. This implies that EDS's management must realise when the WAN design is not optimal. A decision must then be made to change the design to incorporate the correct redundancy. EDS Africa incurs substantial costs related to services supplied by Telkom (the only Telecommunication company allowed to rent WAN data lines to customers in South Africa at this point in time. They are owned by the government.). At present EDS is unable to measure Telkom's up-times using proper historical data, and using applied business statistics. (Tony Webster, 1998). Telkom does not provide EDS with any service level guarantees. When a company out-sources business to EDS, the two parties usually sign a Service Level Agreement (SLA). This agreement will state the network up-time and conditions of conducting business between the two parties. EDS generally excludes Telkom problems from the SLA, as they cannot be held responsible for problems that are outside of their control...

M.Com. (Informatiks) / Please refer to full text to view abstract

M.Comm. / The main aim of this study is to provide an insight on how businesses can use the Internet to enhance their existing business operations. Towards this aim, there are the following secondary aims. Explaining what the Internet can and cannot do, and the tools required. Identifying the current risks involved with the Internet and their impact on business. Providing a possible strategy to follow when planning on using the Internet for business. The output of this study should provide clear guidelines to any South African organisation on why they should utilise, or alternatively, avoid the Internet.

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering, 2016 / Data-intensive research computing requires the capability to transfer les over long distances at high throughput. Stateful rewalls introduce su cient packet loss to prevent researchers from fully exploiting high bandwidth-delay network links [25]. To work around this challenge, the science DMZ design [19] trades o stateful packet ltering capability for loss-free forwarding via an ordinary Ethernet switch. We propose a novel extension to the science DMZ design, which uses an SDN-based rewall. This report introduces NFShunt, a rewall based on Linux's Net lter combined with OpenFlow switching. Implemented as an OpenFlow 1.0 controller coupled to Net lter's connection tracking, NFShunt allows the bypass-switching policy to be expressed as part of an iptables rewall rule-set. Our implementation is described in detail, and latency of the control-plane mechanism is reported. TCP throughput and packet loss is shown at various round-trip latencies, with comparisons to pure switching, as well as to a high-end Cisco rewall. Cost, as well as operations and maintenance aspects, are compared and analysed. The results support reported observations regarding rewall introduced packet-loss, and indicate that the SDN design of NFShunt is a technically viable and cost-e ective approach to enhancing a traditional rewall to meet the performance needs of data-intensive researchers / GS2016

A research report submitted to the Faculty of Engineering and the Built Environment of the University of the Witwatersrand in partial fulfilment of the requirements for the degree of Master of Science in Engineering February 2017 / Software-defined networking (SDN) is the physical separation of the control and data planes in networking devices. A logically centralised controller plane which uses a network-wide view data structure to control several data plane devices is another defining attribute of SDN. The centralised controllers and the network-wide view data structure are difficult to scale as the network and the data it carries grow. Solutions which have been proposed to combat this challenge in SDN lack the use of the statistical properties of the workload or network traffic seen by SDN controllers. Hence, the objective of this research is twofold: Firstly, the statistical properties of the controller workload are investigated. Secondly, Autoregressive Integrated Moving Average Models (ARIMA) and Artificial Neural Network (ANN) models are investigated to establish the feasibility of forecasting the controller workload signal. Representations of the state of the controller plane in the network-wide view in the form of forecasts of the controller workload will enable control applications to detect dwindling controller resources and therefore alleviate controller congestion. On the other hand, realistic statistical traffic models of the controller workload variable are sought for the design and evaluation of SDN controllers. A data center network prototype is created by making use of an SDN network emulator called Mininet and an SDN controller called Onos. It was found that 1–2% of flows arrive within 10 s of each other and more than 80% have inter-arrival times in the range of 10 s–10ms. These inter-arrival times were found to follow a beta distribution, which is similar to findings made in Machine Type Communications (MTC). The use of ARIMA and ANN to forecast the controller workload established that it is feasible to forecast the workload seen by SDN controllers. The accuracy of these models was found to be comparable for continuously valued time series signals. The ANN model was found to be applicable even in discretely valued time series data. / MT2017

Lam Wan. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 139-145). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.