National Backbone Network Research Articles

Impact of Digital Economy and Value Creation on the Profitability of Multinational Enterprises in Nigeria

The study empirically evaluates the impact of broadband penetration and value creation on the profitability of MNEs in Nigeria. The study adopted the survey research design to elicit responses from 1000 Nigerians that were randomly sampled with an e-questionnaire and 152 staff of NCC. The Cronbach Alpha model shows overall reliability of 0.706. The result from the multiple regression from the 1000 Nigerians shows an Adjusted R-square of 0.230 which explains that 23.0% of the variability of profitability is explained by broadband penetration and value creation. The correlation coefficient result shows that there is a significant and moderate relationship between profitability and broadband penetration with a value of 0.414. Similarly, profitability and value creation also show a significant and moderate relationship with a value of 0.359. However, the relationship between value creation and broadband penetration was significant and moderately correlated at 0.346. The Adjusted R-square of 0.040 for the 152 staff of NCC shows that 4.0% of the variability of profitability is explained by broadband penetration and value creation. The correlation coefficient shows that there is a positive but weak relationship between profitability and broadband penetration of 0.111. Also, profitability and value creation have a positive but weak relationship of 0.215. More so, broadband penetration and value creation show a positive but weak relationship of 0.159. The F-statistic value of 4.115 and a P-value of 0.018 indicates that the variables are statistically significant. The study recommended that the Nigerian Communication Commission should develop a national backbone network through which Nigerians can access the internet rather than relying on mobile broadband whose coverage is limited in rural areas.

German Seismic and Infrasound Networks Contributing to the European Integrated Data Archive (EIDA)

Abstract Germany has a long history in seismic instrumentation. The installation of the first station sites was initiated in those regions with seismic activity. Later on, with an increasing need for seismic hazard assessment, seismological state services were established over the course of several decades, using heterogeneous technology. In parallel, scientific research and international cooperation projects triggered the establishment of institutional and nationwide networks and arrays also focusing on topics other than monitoring local or regional areas, such as recording global seismicity or verification of the compliance with the Comprehensive Nuclear-Test-Ban Treaty. At each of the observatories and data centers, an extensive analysis of the recordings is performed providing high-level data products, for example, earthquake catalogs, as a base for supporting state or federal authorities, to inform the public on topics related to seismology, and for information transfer to international institutions. These data products are usually also accessible at websites of the responsible organizations. The establishment of the European Integrated Data Archive (EIDA) led to a consolidation of existing waveform data exchange mechanisms and their definition as standards in Europe, along with a harmonization of the applied data quality assurance procedures. In Germany, the German Regional Seismic Network as national backbone network and the state networks of Saxony, Saxony-Anhalt, Thuringia, and Bavaria spearheaded the national contributions to EIDA. The benefits of EIDA are attracting additional state and university networks, which are about to join the EIDA community now.

Internet Infrastructure in Africa: Status and Opportunities

There is a major information gap in Africa, where access to information is structurally disabled.This study was conducted taking the University of Dodoma in Tanzania as a case study. The causes for poor internet access were identified as: Lack of alignment between last-mile, middle-mile, and long-range network infrastructure; Tyranny of bad on-premises network design; Up to 15 network hops just to leave on-premises network architecture; Lack of best-practice templates and benchmarks for on-premises, middle-mile and national backbone network architecture in emerging and developing markets; and local operators charging exorbitant bandwidth prices. The US Federal Communication Commission’s (FCC) definition of broadband is 25 Mbps per host. The World Bank defines broadband as 12 Mbps per hundred consumers.According to the United Nations, broadband is a basic human right and an absolute necessity for productivity and sustainable growth

Route, Modulation Format, MIMO, and Spectrum Assignment in Flex-Grid/MCF Transparent Optical Core Networks

In this paper, we target an optimal multiple-input multiple-output digital signal processing (MIMO-DSP) assignment to super-channels affected by intercore crosstalk (ICXT) in multicore fiber (MCF) enabled transparent optical core networks. MIMO-DSP undoes ICXT effects, but can be costly with high core density MCFs. Hence, its implementation in the network must be carefully decided. We address our objective as a joint route, modulation format, MIMO and spectrum assignment (RMMSA) problem, for which integer linear programming formulations are provided to optimally solve it in small network scenarios. Moreover, several heuristic approaches are also proposed to solve large-scale problem instances with good accuracy. Their goal is to minimize both network spectral requirements and the amount of MIMO equalized super-channels, taking a crosstalk-free space division multiplexing (SDM) solution as a reference, for example, based on parallel single mode fibers [i.e., a multifiber (MF) scenario]. For our evaluation, we consider several state-of-the-art MCF prototypes and different network topologies. The obtained results, with the considered MCFs, disclose that in national backbone networks, the desirable percentage of super-channels with MIMO equalization to match the performance of an equivalent crosstalk-free SDM solution ranges from 0% to 36, while in continental-wide networks this range raises from 0% to 56%. In addition, in the case of a nonideal MIMO (with a 3 dB/km of crosstalk compensation), such percentages range from 0% to 28% and from 0% to 45% in national and continental-wide backbone networks, respectively, experimenting a performance gap up to 12% with respect to the MF reference scenario.

Including Failure Correlation in Availability Modeling of a Software-Defined Backbone Network

Software-defined networking (SDN) promises to improve the programmability and flexibility of networks, but also brings new challenges that need to be explored. The main objective of this paper is to include failure correlation in a quantitative assessment of the properties of SDN backbone networks to determine whether they can provide similar availability as the traditional IP backbone networks. To achieve this goal, this paper has formalized a two-level availability model that captures the global network connectivity without neglecting the essential details and which includes a failure correlation assessment. This paper proposes a modular and systematic approach for characterizing the principal minimal-cut sets in both SDN and traditional networks, and stochastic activity network models for characterizing the single network elements. To demonstrate the feasibility of the model, an extensive sensitivity analysis has been carried out on a national backbone network.

Flex-Grid/SDM Backbone Network Design with Inter-Core XT-Limited Transmission Reach

Spatial division multiplexing (SDM) has been presented as a key solution to circumvent the nonlinear Shannon limit of standard single-core fibers. To implement SDM, multi-core fiber (MCF) technology becomes a top candidate that is leveraged by the very low inter-core crosstalk (XT) measurements obtained in real laboratory MCF prototypes with up to 22 cores. In this work, we concentrate on the design of MCF-enabled optical transport networks. To this goal, we present a methodology to estimate the worst-case transmission reach of the optical signals (at different bit rates and modulation formats) across MCFs given real laboratory XT measurements. Next, we present an optimal integer linear programming (ILP) formulation for the design of a flex-grid/SDM optical transport network that makes use of the transmission reach estimations. Additionally, an effective simulated annealing (SA)-based heuristic able to solve large problem instances with reasonable execution times is presented. Once the proposed heuristic is adequately tuned and validated, we use it to compare the resource utilization in MCF-enabled network scenarios against currently available multi-fiber link solutions. Numerical results reveal very close performances with up to 19 cores/fibers in national backbone network scenarios and up to 12 cores/fibers in long-haul continental ones.

Switchless Elastic Rate Node (SERANO) Architecture: A Universal Node for Optical Grooming and Adaptive Networking

The switchless elastic rate node (SERANO) is an elastic optical network block architecture facilitating reduction in network cost and blocking due to spectral fragmentation while extending the capacity-reach product in translucent optical networks. We present an analytical mathematical method for minimizing the number of transceivers that are solely used to construct this block, albeit a finite blocking probability. Moreover, based on a realistic traffic matrix and making use of a networking planning tool, we deduce a SERANO's block dimension for BT's national backbone network. Finally, we estimate the conditions under which the cost of a SERANO block is lower to the corresponding electronic switch for providing important networking functions like 3R regeneration, defragmentation, and network reoptimization.

홍수 및 환경 감시망의 보안성 강화를 위한 단방향 Bypass TAP 장치 개발에 관한 연구

Abstract The flood and environment surveillance network on riverside is a network requiring a way to efficiently manage the information from all kinds of sensors, along with an optical communication device that can deliver high-quality video information at high speed. Since on-site prompt recovery is very important especially for communication problems that occurred due to cut-off or aged network, various researches have been carried out on this. However, because the security against outside hacking or outside intrusion with illegal purposes is very important for environment surveillance network, such as the national backbone network, an efficient network maintenance and repair should be enabled while satisfying security and reliability at the same time. A characteristic of requirement is that when security is improved, the efficiency of maintenance and repair drops as they are conflicting to each other. Therefore, this research proposed a system in order to satisfy the conflicting requirement and improve security, by developing a one-way Bypass TAP and an android-based smartphone app that can enable efficient network maintenance and repair.

A New Network Traffic Classification Method Based on Classifier Integration

With development of scale, diversity and complexity of network traffic, the drawbacks of traditional machine learning methods on traffic classification is gradually exposed, especially the false positive problem in large-scale real network traffic classification is particularly serious. In this paper, aiming at reducing the false positive rate of network traffic classification, an effective network traffic classification method --- CMM method. CMM method contains three steps, including dividing the training set into clusters, forming sub-classifiers, and classifier integration in accordance with the principle of minimization and maximization. In this paper, we firstly demonstrate the effectiveness of this method in reducing the false positive rate. Secondly, we conduct experiments in large-scale national backbone network, such as the SSL protocol classification and experimental results verify the effectiveness of this method in large-scale the actual network traffic classification.

Investment models and regulatory constraints for broadband backbone roll‐out in selected African countries

PurposeThis paper seeks to identify policy and regulatory bottlenecks that need to be overcome in order to stimulate private sector investment in backbone networks in selected African countries (Côte d'Ivoire, Ethiopia, Kenya, South Africa and Uganda).Design/methodology/approachIt does so by exploring policy and regulatory frameworks and market structures that influence investment decisions on backbone infrastructure roll‐out; it investigates models and strategies adopted by the public sector to finance national backbone infrastructure; and it provides recommendations on how to stimulate private investment in backbone roll‐out by creating an enabling policy and regulatory environment.FindingsResearch findings show that the telecommunications sector in the selected African countries has witnessed the return of state‐led investment in the roll‐out of fibre backbones. The rationale for state‐led intervention has often been cited as market failure regarding investment in broadband backbone roll‐out. However, many of the policy and regulatory barriers to market entry remain, including protectionist legislation, which has limited private sector participation in investing in backbone.Practical implicationsThe reality is that African governments are maintaining control over national backbones and, in some markets where the telecommunications infrastructure sector has been liberalised, the state‐owned operators may enter into direct competition with the private sector or may delay delivery by the private sector.Originality/valueThe value of the paper is that it provides evidence on how to improve the roll‐out and extension of national broadband backbone networks through the development of a policy and regulatory framework which facilitates private sector investment in this sector. The paper also makes recommendations to governments for the facilitation of private investment in backbone networks through the development of an enabling policy and regulatory environment.

Traffic grooming in hybrid ring-star optical networks

The increasing demand for Internet network capacity requires optical traffic-grooming technology to reduce the complexity of the network. A network with optical cross connects is one potential architecture to achieve this goal. We show that an alternate architecture based on a hybrid ring-star topology and waveband grooming helps to reduce the network complexity by minimizing the number of nodes and the number of ports required in each node. We develop an analytical method for the design of hybrid ring-star topologies to reduce the capital cost of the overall optical network. We evaluate the performance of our method in terms of the number of network elements required for a national backbone network and demonstrate its savings in comparison to waveband grooming.

고성능 네트워크에서 인터넷 웜 확산 모델링

최근 정보기술의 발달로 통신, 방송, 인터넷 등의 모든 서비스들이 하나의 네트워크로 통합되는 광대역 통합망이 등장하게 되었다. 그러나 이에 대한 역기능으로 다양한 위협이 등장하고 있으며, 그 중 인터넷 웜과 같은 악성 코드는 국가 기간망을 뒤흔드는 혼란을 초래할 수 있다. 본 논문은 고성능 네트워크 환경에서 웜 확산에 대한 정확한 예측을 그 목표로 한다. 이를 위해 인터넷 쉽게 적용 가능한 확산 모델을 살펴보고, 여러 인터넷 웜을 적용하여 인터넷 환경에서 동작 방식을 분석한다. 제안 모델은 웜 확산 단계와 대응 단계에 따른 영향을 분석하여 인터넷 웜의 확산 규모와 속도를 보다 정확하게 예측할 수 있다. 본 논문의 결과는 광대역 통합 네트워크와 같은 고성능 네트워크에도 적용할 수 있다. Recently broadband convergence network technology is emerging as an integrated network of telecommunication, broadcasting and Internet. But there are various threats as side effects against the growth of information technology, and malicious codes such af Internet worms may bring about confusions to upset a national backbone network. In this paper, we survey the traditional spreading models and propose a new worm spreading model on Internet environment. We also analyze the spreading effects due to tile spread period and the response period of Internet worms. The proposed model leads to a better prediction of the scale and speed of worm spreading. It can be applied to high-speed network such as broadband convergence network.

6.6.1 A Systems Engineering Approach to Filling India's Telecommunications Gap

AbstractThe need of developing nations to increase information flow provides a commercial opportunity to extend modern telecommunications technologies and service offerings into new markets. This high‐level case study identifies the need for new systems in India to assist in filling telecommunications service gaps, with a strong emphasis on systems for rural populations. The United States is used as a basis of comparison. Existing systems and deficiencies, stakeholders, and evaluation criteria for potential alternatives are discussed. Several alternatives for local service delivery and national backbone networks are presented, drawn from current and planned offerings in India and worldwide. Application of the criteria to the candidate solutions indicates that no single one is preferable, but a combination of several would provide a suitable solution.

Network performance and integrity enhancement with optical path layer technologies

Path layer technologies will play a key role in the development of a powerful and failure resilient B-ISDN. So far, they have been based on electrical technologies. This paper highlights WDM/FDM techniques and demonstrates that optical paths can greatly enhance the path layer capability and, therefore, the network performance. It is also shown that effective network failure restoration can be achieved with optical paths. The applicability of the wavelength path (WP) technique to global area networks is revealed by comparing different optical path realization techniques. WPs are applied to the national backbone network example to evaluate the required number of wavelengths, and to identify optical cross-connect node requirements. It then proposes a new optical path concept: the virtual wavelength path (VWP). In the VWP scheme, wavelengths are assigned on a link-by-link basis. In other words, the wavelength assigned to a wavelength path has only local significance. Significant benefits of the VWP such as the simplified path accommodation design within a transmission facility network and the reduced number of wavelengths needed, are elucidated. An optical cross-connect node architecture that enables the VWPs is also proposed. The architecture allows the VWP concept to be realized with commercially available optical technologies. The optical path layer concept proposed exploits and consolidates the layered transport network architecture and optical technologies, and will open up new opportunities for creating a B-ISDN that is bandwidth abundant and has a high degree of integrity.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

From JANET to SuperJANET

Abstract JANET is a national backbone network which provides data communications services for the UK Higher Education and Research Community. The network is operated under the authority of the Secretary of State at the Department of Education and Science. Funding is provided by a number of agencies among which the Computer Board takes lead responsibility. The aim of the network is to provide a unified and pervasive communications infrastructure capable of supporting a wide range of academic and research activities. The principle of open communications based on non-proprietary standards has been the foundation of the network since its inception. The network currently serves nearly 200 sites, one third of which are connected at 64 kbps. The JANET MK II programme is a performance upgrade with the objective of providing network access at 2 Mbps for more than 50 sites, and part of this upgrade is already in service. The longer term plans envisage the development of a SuperJANET with a major increase in the both the scope of the network and its performance. SuperJANET will be a broadband network capable of supporting new styles of communication such as multi-media and video and offering new opportunities for research and education. SuperJANET will also offer a testbed to support IT research activities and the close association between research and service networks will accelerate the development of new network services based on the results of UK and European IT Research.

Traffic characterization of the NSFNET national backbone

Traditionally, models of packet arrival in communication networks have assumed either Poisson or compound Poisson arrival patterns. A study of a token ring local area network (LAN) at MIT [5] found that packet arrival followed neither of these models. Instead, traffic followed a more general model dubbed the “packet train,” which describes network traffic as a collection of packet streams traveling between pairs of nodes. A packet train consists of a number of packets travelling between a particular node pair. This study examines the existence of packet trains on NSFNET, a high speed national backbone network. Train characteristics on NSFNET are not as striking as those found on the MIT local network; however, certain protocols exhibit quite strong train behavior given the great number of hosts communicating through the backbone. Descriptions of the packet train model can be found in [3] and [5].

NSF, NASA link computers

The National Science Foundation (NSF) has signed an agreement with the National Aeronautics and Space Administration (NASA) to share high‐speed communications lines. The effort will link university researchers now connected to NSF's national computer communications network with data bases and supercomputers at NASA laboratories. “NSF and NASA have agreed to work together to identify ways to satisfy the technical requirements of networking through research, engineering, and implementations,” according to Steve Wolff, NSF Division Director for Networking and Communications Research and Infrastructure.The 5‐year agreement will allow three NASA facilities to link to existing NSF regional networks, which in turn are connected through a national backbone network. The NASA Goddard Space Flight Center in Greenbelt, Md., will be linked to the Southeastern Universities Research Associated Net (SURANET); the NASA Ames Research Center in Moffett Field, Calif., will be linked to the Bay Area Regional Research Net (BARR‐NET); and the NASA Johnson Space Flight Center in Houston, Tex., will be linked to Sesquinet, a regional network in Texas. Authorized scientists will be able to access and use NASA data in their research, and can apply for time on NASA supercomputers. NASA‐funded scientists at universities served by NSF regional networks will be able to communicate and collaborate with their colleagues at NASA centers.