Understanding the effectiveness of open standards for providing access to functions in next generation networks

University of Technology, Sydney. Faculty of Engineering and Information Technology.The traditional telecommunications environment is 'closed', where applications can only be developed internally with specific knowledge of individual network technologies. In the last several years, there has been an enormous increase in efforts to 'open up ' these networks for application development, leading to open standards such as the Parlay/OSA APIs. This thesis is primarily concerned with understanding the effectiveness of open standards for providing third party stakeholders with access to functions in Next Generation Networks. Effectiveness in this context is to do with how well open systems may, and can, enable the business aims, and consequent technological advantages to achieve the business aims. We reason about the effectiveness from three perspectives in terms of whether the open standard provides sufficient openness, functional coverage, and practicality. While the methodology and models are applicable to evaluating open standards in general, we specifically apply them to the QoS control functionality provided by the Parlay/OSA Connectivity Manager Service Capability Feature

Towards Automated Network Configuration Management

Modern networks are designed to satisfy a wide variety of competing goals related to network operation requirements such as reachability, security, performance, reliability and availability. These high level goals are realized through a complex chain of low level configuration commands performed on network devices. As networks become larger, more complex and more heterogeneous, human errors become the most significant threat to network operation and the main cause of network outage. In addition, the gap between high-level requirements and low-level configuration data is continuously increasing and difficult to close. Although many solutions have been introduced to reduce the complexity of configuration management, network changes, in most cases, are still manually performed via low--level command line interfaces (CLIs). The Internet Engineering Task Force (IETF) has introduced NETwork CONFiguration (NETCONF) protocol along with its associated data--modeling language, YANG, that significantly reduce network configuration complexity. However, NETCONF is limited to the interaction between managers and agents, and it has weak support for compliance to high-level management functionalities. We design and develop a network configuration management system called AutoConf that addresses the aforementioned problems. AutoConf is a distributed system that manages, validates, and automates the configuration of IP networks. We propose a new framework to augment NETCONF/YANG framework. This framework includes a Configuration Semantic Model (CSM), which provides a formal representation of domain knowledge needed to deploy a successful management system. Along with CSM, we develop a domain--specific language called Structured Configuration language to specify configuration tasks as well as high--level requirements. CSM/SCL together with NETCONF/YANG makes a powerful management system that supports network--wide configuration. AutoConf supports two levels of verifications: consistency verification and behavioral verification. We apply a set of logical formalizations to verifying the consistency and dependency of configuration parameters. In behavioral verification, we present a set of formal models and algorithms based on Binary Decision Diagram (BDD) to capture the behaviors of forwarding control lists that are deployed in firewalls, routers, and NAT devices. We also adopt an enhanced version of Dyna-Q algorithm to support dynamic adaptation of network configuration in response to changes occurred during network operation. This adaptation approach maintains a coherent relationship between high level requirements and low level device configuration. We evaluate AutoConf by running several configuration scenarios such as interface configuration, RIP configuration, OSPF configuration and MPLS configuration. We also evaluate AutoConf by running several simulation models to demonstrate the effectiveness and the scalability of handling large-scale networks

A novel approach to emergency management of wireless telecommunication system

The survivability concerns the service continuity when the components of a system are damaged. This concept is especially useful in the emergency management of the system, as often emergencies involve accidents or incident disasters which more or less damage the system. The overall objective of this thesis study is to develop a quantitative management approach to the emergency management of a wireless cellular telecommunication system in light of its service continuity in emergency situations – namely the survivability of the system. A particular wireless cellular telecommunication system, WCDMA, is taken as an example to ground this research.The thesis proposes an ontology-based paradigm for service management such that the management system contains three models: (1) the work domain model, (2) the dynamic model, and (3) the reconfiguration model. A powerful work domain modeling tool called Function-Behavior-Structure (FBS) is employed for developing the work domain model of the WCDMA system. Petri-Net theory, as well as its formalization, is applied to develop the dynamic model of the WCDMA system. A concept in engineering design called the general and specific function concept is applied to develop a new approach to system reconfiguration for the high survivability of the system. These models are implemented along with a user-interface which can be used by emergency management personnel. A demonstration of the effectiveness of this study approach is included.There are a couple of contributions with this thesis study. First, the proposed approach can be added to contemporary telecommunication management systems. Second, the Petri Net model of the WCDMA system is more comprehensive than any dynamic model of the telecommunication systems in literature. Furthermore, this model can be extended to any other telecommunication system. Third, the proposed system reconfiguration approach, based on the general and specific function concept, offers a unique way for the survivability of any service provider system.In conclusion, the ontology-based paradigm for a service system management provides a total solution to service continuity as well as its emergency management. This paradigm makes the complex mathematical modeling of the system transparent to the manager or managerial personnel and provides a feasible scenario of the human-in-the-loop management

New venture internationalisation and the cluster life cycle: insights from Ireland’s indigenous software industry

The internationalization of new and small firms has been a long-standing concern of researchers in international business (Coviello and McAuley, 1999; Ruzzier et al., 2006). This topic has been re-invigorated over the last decade by the burgeoning literature on so-called ‘born globals’ (BG) or ‘international new ventures’ (INV) – businesses that confound the expectations of traditional theory by being active internationally at, or soon after, inception (Aspelund et al., 2007; Bell, 1995; Rialp et al., 2005). Until quite recently, this literature had not really considered how the home regional environment of a new venture might influence its internationalization behaviour. However, a handful of recent studies have shown that being founded in a geographic industry ‘cluster’ can positively influence the likelihood of a new venture internationalizing (e.g., Fernhaber et al., 2008; Libaers and Meyer, 2011). This chapter seeks to build on these recent contributions by further probing the relationship between clusters and new venture internationalization. Specifically, taking inspiration from recent work in the thematic research stream on clusters (which spans the fields of economic geography, regional studies and industrial dynamics), the chapter explores how the emergence and internationalization of new ventures might be affected by the ‘cluster life cycle’ context within which they are founded. This issue is examined through a revelatory longitudinal case study of Ireland’s indigenous software cluster. The study investigates the origins and internationalization behaviour of ‘leading’ Irish software ventures but, in contrast to many existing studies, it seeks to understand these firms within the context of the Irish software cluster’s emergence and evolution through a number of ‘life-cycle’ stages

Operational support systems for satellite communications

The role of satellite communications is changing from providing bandwidth linking network operators interconnections towards providing IP enabled communications to end users. This migration from few high-value routes towards many low-value routes means that integration and automation of processes with terrestrial networks becomes critical in driving down unit costs. Integration and automation is necessary on all planes: user, control and management. In satellite communications, management aspects, underpinned by Operational Support Systems (OSS) have received the least research attention, making this a valuable topic for study. In most areas, OSS for satellite systems are similar to other domains. However there are some notable areas of difference which have been the focus of this research. The eTOM business framework, developed by the TMF, has been used to highlight aspects of OSS unique to satellite. Since satellite capacity represents the highest operational cost of a satellite route, effective management while minimising the overhead traffic is critical. The transmission of IP packets is assumed and the real-time measurement of QoS parameters such as packet delay and loss emerged as the most important differences. A number of approaches to QoS measurement are feasible, however the use of trace packets is most promising especially for high network loads. An experiment compares the results from simulations, mathematical models and from a test network, using Poisson and self-similar traffic flows. The relationship between measurement accuracy and trace packet intensity is explored and the measurement response time to steps in traffic load is estimated. It is discovered that measurement accuracy improves as the queue load increases, in contrast to alternative approaches such as sampling of user packets. The response time to steps depends upon the degree of self-similarity and is generally longer than the times recommended by standards. A pragmatic approach to management of different modes is proposed where the measurement method is changed depending on the load

Redes de telecomunicações móveis em Portugal: análise retrospectiva

Mestrado em Engenharia de Computadores e TelemáticaPortugal é um dos países da União Europeia (UE) com maior taxa de penetração do Serviço Telefónico Móvel (STM) o que o torna num dos países mais interessantes para estudos relacionados com redes e serviços M´oveis. Neste contexto os estudos de mercado para determinar a taxa de penetração de um novo serviço / tecnologia tornam-se decisivos para as empresas uma vez que podem implicar custos elevados por vezes muito difíceis de rentabilizar. Apesar de já existir algum software que permite fazer modelação do comportamento de vários operadores de telecomunicações em determinados cenários, esses modelos têm em consideração padrões de comportamento teóricos e podem não estar inteiramente adaptados à realidade de cada mercado. Este trabalho procura melhorar esses padrões de comportamento fazendo uma análise retrospectiva ao mercado do STM desde a sua introdução em Portugal, em 1989, e assim fornecer dados mais precisos às ferramentas de modelação.Portugal is one of the European Union (EU) countries with the highest penetration rate of Mobile Telecommunications Service (MTS) and that fact makes it one of the most interesting countries for conducting studies related to mobile networks and services. In this context, doing market research to determine the penetration rate of a particular new service / technology becomes crucial for companies, since it may involve high costs sometimes very difficult to monetize. Although there is already some software that models the behavior of several telecom operators in certain scenarios, these models take into account patterns of behavior based only on theory which may not be fully adapted to each market reality. This work seeks to improve those patterns of behavior by a making a retrospective market analysis of the MTS, since its introduction in Portugal in 1989 thus providing more accurate data for modeling tools

Assessment of water pollution arising from copper mining in Zambia: a case study of Munkulungwe stream in Ndola, Copperbelt province

Water pollution is recognized as one of the major environmental problems in the mining industry. This has been compounded with an increase in agriculture activities. Water pollution is a major problem on copper and coal mines throughout the world and Zambia, the focus of this study, is no exception. Worldwide freshwater resources, which provide important ecosystem services to humans, are under threat from rapid population growth, urbanization, industrialization and abandonment of wastelands. There is an urgent need to monitor and assess these resources. In this context, the physical, chemical and ecological water quality of the Munkulungwe Stream located on the Copperbelt of Zambia, was assessed with possible contamination from Bwana Mkubwa TSF, agriculture activities and subsequent impact on the surrounding community. The chemical and physical parameters were assessed at four sampling locations. Sampling site S1 was located on the Munkulungwe stream upstream of Bwana Mkubwa TSF, S2, S3 and S4 were on the main stream downstream of Bwana Mkubwa TSF. In addition, a macroinvertebrate composition analysis was performed to estimate the quality of water using the biotic index score. Finally, the relationship between physiochemical parameters and biotic index score was analysed to interrogate their inter-relationship with respect to water quality. The results showed that the average values of dissolved oxygen (DO) of 4.52 mg/l, turbidity (40.96 NTU), Co (0.24 mg/l), Pb (0.25 mg/l), Fe (0.36 mg/l) and Mn (0.22 mg/l) downstream exceeded international standards for drinking water. Upstream, the values of Co, Pb, Fe and Mn were within acceptable standards for drinking water, DO and turbidity were above acceptable standards. The metal concentration and total dissolved solutes were impacted by closeness to the mine tailings deposit with the heavy metal concentration being highest at S2 and S3. Moreover, high turbidity levels revealed that land erosion induced by agriculture activities is a severe problem in the area. Physical parameters were high in the rainy season due erosion escalated by rains while chemical parameters were high post rainy season. During the rainy season, the chemical contaminants are diluted and thus they are not such a big impact, but they tend to concentrate up during the dry MDNLEE001 III season. The stream at sampling points S2 and S3 was dominated by species tolerant (leech, Isopod and Snail: Pouch) and semi tolerant (Blackfly larvae and Amphipod or Scud) to pollution. The change in season influenced the composition of macroinvertebrates, with the number of species increased post rainy season. The average biotic index score (2.5) showed that the stream condition is not good, it is slightly polluted. The results showed that water quality downstream was substantially affected by Bwana Mkubwa TSF, agriculture activities and is likely to affect human health and food security. It is recommended that groundwater surrounding tailings dams should be monitored in both active and abandoned mines. Curtain boreholes around a tailings dam can be drilled and the water extracted and treated so that it doesn't contaminate other water bodies. To improve the environmental management of mining related impacts in Zambia, mining areas should be completely rehabilitated. There is need for remediation strategies for abandoned mine sites. Constructed wetlands, roughing filtration and phytoremediation are highly promising techniques, as they are reliable, cheap, effective and sustainable

Security Management System for 4G Heterogeneous Networks

There is constant demand for the development of mobile networks to meet the service requirements of users, and their development is a significant topic of research. The current fourth generation (4G) of mobile networks are expected to provide high speed connections anywhere at any time. Various existing 4G architectures such as LTE and WiMax support only wireless technologies, while an alternative architecture, Y-Comm, has been proposed to combine both existing wired and wireless networks. Y-Comm seeks to meet the main service requirements of 4G by converging the existing networks, so that the user can get better service anywhere and at any time. One of the major characteristics of Y-Comm is heterogeneity, which means that networks with different topologies work together to provide seamless communication to the end user. However, this heterogeneity leads to technical issues which may compromise quality of service, vertical handover and security. Due to the convergence characteristic of Y-Comm, security is considered more significant than in the existing LTE and WiMax networks. These security concerns have motivated this research study to propose a novel security management system. The research aims to meet the security requirements of 4G mobile networks, e.g. preventing end user devices from being used as attack tools. This requirement has not been met clearly in previous studies of Y-Comm, but this study proposes a security management system which does this. This research follows the ITU-T recommendation M.3400 dealing with security violations within Y-Comm networks. It proposes a policy-based security management system to deal with events that trigger actions in the system and uses Ponder2 to implement it. The proposed system, located in the top layer of the Y-Comm architecture, interacts with components of Y-Comm to enforce the appropriate policies. Its four main components are the Intelligent Agent, the Security Engine, the Security Policies Database and the Security Administrator. These are represented in this research as managed objects to meet design considerations such as extensibility and modifiability. This research demonstrates that the proposed system meets the security requirements of the Y-Comm environment. Its deployment is possible with managed objects built with Ponder2 for all of the components of Y-Comm, which means that the security management system is able to prevent end user devices from being used as attack tools. It can also achieve other security goals of Y-Comm networks