Universal Broadband Research Articles

Towards a theory of synchronous technological assimilation: The case of Korea's Internet economy

While traditional theories of economic development and the dynamics of late industrialization explain Korea's phenomenal transformation into a major industrial power in only three decades, they fall short of explaining the timing of its ascent to the world's top technological hub, measured in terms of universal broadband installation and Internet usage, i.e., its leadership position in the Internet-centric economy. Moreover, Korea's socio-cultural factors, acknowledged to have enhanced learning and individual motivation as an integral part of Korea's economic transformation, are not sufficient by themselves in explaining Korea's ability to leapfrog over their American, Japanese, and European counterparts. In a departure from stage-of-growth and late industrialization theories, we introduce three synchronous conditions to account for Korea's leapfrogging dynamics: (1) the application of new technologies, (2) the emerging new pattern of individual consumption, and (3) a supporting logic of enterprise that links these two conditions. In adapting these conditions to the case of Korea, we argue that the first two can apply to any generic technological environment, but that the logic of enterprise is inextricably linked to unique Korean cultural values and institutions. In doing so, we hope to unpack the linkage between technological learning, advancement, and national culture.

Design of Universal Broadband Visible Antireflection Coating for Commonly Used Glass Substrates

We designed a universal broadband visible antireflection coating for glass substrates with refractive indices ranging from 1.45 to 1.90 by a jumping search technique. The jumping search algorithm, based on the searches of layer-thickness jump tuning and layer jump elimination, was used to refine the mean visible antireflection performance and simplify the design structure of a multilayer system. It was shown that the universal visible antireflection coating designs for a set of 10 different substrates with the refractive indices of 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75, 1.80, 1.85, and 1.90, obtained by different types of jumping search of a two-material 50-layer system, were reduced to 18–22-layered structures and their total average universal visible reflectivities reduced to approximately 0.307–0.309% were acceptable.

Flow-aware link dimensioning for guaranteed-QoS services in broadband convergence networks

In this work, <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> we propose an analytic framework for dimensioning the link capacity of broadband access networks which provide universal broadband access services to a diverse kind of customers such as patient and impatient customers. The proposed framework takes into account the flow-level quality of service (QoS) of a connection as well as the packet-level QoS, via which a simple and systematic provisioning and operation of the network are provided. To that purpose, we first discuss the necessity of flow-aware network dimensioning by reviewing the networking technologies of the current and future access network. Next, we propose an analytic model for dimensioning the link capacity for an access node of broadband convergence networks which takes into account both the flow and packet level QoS requirements. By carrying out extensive numerical experiment for the proposed model assuming typical parameters that represent real network environment, the validity of the proposed method is assessed.

Universal Visible Antireflection Coating Designs for Various Substrates

A design procedure, based on the flip-flop tuning search algorithm, is applied to design universal visible antireflection coatings for various substrates with indices 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75 and 1.784. The universal broadband antireflection coating designs obtained by the flip-flop tuning method for a two-material and a three-material system with 80 sublayers of 300 nm thickness starting at high index and middle index lead to 10-layer structures, and the average reflectivities of these designs for the eight different substrates over the entire visible spectral region (400–750 nm) decrease to lower than 0.199% and 0.201%, respectively. Although the antireflection performance for each substrate is somewhat less than the optimum, it is acceptable for most applications.

DakNet: rethinking connectivity in developing nations

DakNet provides extraordinarily low-cost digital communication, letting remote villages leapfrog past the expense of traditional connectivity solutions and begin development of a full-coverage broadband wireless infrastructure. What is the basis for a progressive, market-driven migration from e-governance to universal broadband connectivity that local users will pay for? DakNet, an ad hoc network that uses wireless technology to provide asynchronous digital connectivity, is evidence that the marriage of wireless and asynchronous service may indeed be the beginning of a road to universal broadband connectivity. DakNet has been successfully deployed in remote parts of both India and Cambodia at a cost two orders of magnitude less than that of traditional landline solutions.

Universal Broad-Band Antireflection Coating Designs for Substrates in the Visible Spectral Region

We have designed broad-band normal-incidence antireflection coatings over the visible spectral region for a set of eight various substrates with indices 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75 and 1.784. It is shown that the calculated average reflectance of the eighty-layer flip–flop antireflection coating design for substrates over the 400–750 nm spectral region can be reduced to less than 0.34%, which is acceptable.

Achieving Universal Broadband Access: The Canadian Approach

Achieving Universal Broadband Access: The Canadian Approach

Metropolitan Telecommunications Policy

In implementing its mandate for telecommunications deregulation the Federal Communications Commission has virtually ignored an important set of telecommunications issues affecting local governments and their suburban and urban constituencies. This paper reviews the very circumscribed role provided for local public sector involvement in telecommunications issues in the Telecommunications Act of 1996 and suggests that role is an insufficient predicate for state and local governments to address telecommunications governance issues that cannot be effectively addressed through centralized FCC policy: e.g., urban and suburban telecommunications infrastructure governance; open access issues; planning for universal broadband service across metropolitan areas; metropolitan approaches to the digital divide and the E Rate; development of community networks; regional economic competitiveness; urban network security, and digital governance policies. A hypothetical Metropolitan Telecommunications Organization (MTO) is proposed as public-private vehicle to promote local public and community values in telecommunications policy in these subjects as counterweight to the exclusive pursuit of competitive corporate interests that today determine the location, timing and availability of access to broadband services in metropolitan regions. These public values include affordable open access, equal access and universal service policies in the emerging telecommunications networks in metropolitan areas, as well as local public sector options for inducing private sector coordination with public sector initiatives in developing regional, metropolitan or large city institutional infrastructures for high speed high capacity telecommunications for the public sector and for the public at large.

Universal broadband mobility target for post-TINA infrastructure: toward the fourth generation

Future universal broadband mobile services present a challenge for telecommunications architectures, control, and management. The focus of the future mobile (fourth) generation vision is turned from capacity to services, from radio to network-wide issues. New types of applications will evolve that should be supported by an adequate programmable intelligent telecommunications infrastructure. A convergence between telecom and datacom networks will happen based on the communications middleware concept, which will provide universal secure connectivity between mobile users and their applications. Actual specifications of TINA-C do not address all such necessary issues. There is a need for technology evolution, enhancement, and integration to meet these new requirements at different levels. The author the concept of the universal broadband mobile telecommunications systems (UBMTS, or simply UBM) described as fourth-generation mobile systems. The UBMTS objective is both to extend mobile user access to the range of broadband services that will exist for broadband integrated services digital network (B-ISDN) users, and to extend the customization of new services related to personal communications systems (PCS) users.

UniNet: a hybrid approach for universal broadband access using small radio cells interconnected by free-space optical links

A new type of broadband access system is proposed for providing high-quality, bandwidth-upon-demand telecommunication services to the home and office. Communication terminals attach to the network via short radio links, and users can roam freely within a house or building unencumbered by the availability of wired telecommunications outlets. Basic service is extended through small, high-capacity radio cells; the base stations are interconnected via short, highly focused free-space optical links in a multihop mesh arrangement; and the need for new broadband access cabling is totally surmounted. A tiered arrangement of radio cells further extends service to both out-of-building pedestrian and vehicular users, and service is universally available. Benefits of the approach are described, and issues involving reliability, availability, capacity, and hand off are identified and addressed. Opportunities to refine the basic approach are suggested for further study.

Multilevel video coding and distribution architectures for emerging broadband digital networks

There is a renewed interest in video-based communications. The expected proliferation of various video communication applications has in turn resulted in a need for scalable and efficient digital video encoding schemes which would enable the dissemination of video signals at differing spatial resolution, depending on end-user needs and limitations. Also, along with this is the need for a universal broadband in which the same transmitted signal is efficiently distributed to various end-user applications, allowing them to communicate at differing grades of video quality. As a first step, this paper presents an efficient and scalable video coding scheme. The scheme is capable of encoding and decoding video signals in a hierarchical, multilayer fashion to provide video at differing quality grades, e.g., NTSC, extended quality (EQTV), high definition (HDTV). Since the lower levels in such a scheme can be encoded independently of the upper levels, compatibility with some of the standard codecs can be directly imposed. In addition, strategies to control quantization noise for independent transmission by means of residual layering are also discussed. This paper also discusses the utilization of this coding scheme to enable efficient bit rate sharing and robust distribution of video communication signals at three distinct quality grades in multicasting, as well as multipoint communication applications for multiparty video-conferencing. Two special distribution architectures are considered which involve the use of SMDS and ATM as the transport and delivery vehicles.

Performance comparison of media access protocols for Gbit/s networks in the local area

The evolution towards future communication systems is strongly influenced by increasing transmission capacities, changing service requirements and the emerging ATM technology. The next generation of high-performance local and metropolitan area networks has to be designed including control schemes which provide high throughput while simultaneously supporting real-time services. The slotted ring architecture enhanced by spatial slot reuse is one potential approach for data transmission and admission control in distributed Gbit/s networks. Various concepts have been proposed for an efficient medium access control which maintains fairness and bounded access delays. By using simulation results, this paper compares the performance of several protocols: ATMRing (ATMR), CRMA-II (Cyclic Reservation Multiple Access) and MetaRing. First, the differences in their basic mechanisms are generally analysed applying saturated traffic scenarios. Then the behaviour in a multi-service environment is discussed, with particular regard to the requirements of universal broadband services. It is shown that all approaches offer efficient bandwidth sharing mechanisms. They overcome the well-known trade-off between high throughput and strong real-time requirements by providing extended bandwidth for user data and suitable end-to-end delays. Their performance, however, is quite sensitive to the actual network conditions and chosen protocol parameters.

A universal broadband multipoint teleconferencing service for the 21st century

The Personal Presence system moves both the computing power behind advanced video processing and the connectivity behind video teleconferencing into the public switched telephone network where the costs of these resources can be shared by many users on an as used basis. This allows the deployment of much more powerful and sophisticated resources than most users can afford while lowering the cost for each user by eliminating duplication of capital expenditures. Transmission costs associated with multiparty video conferences over wide areas are also lowered because of the connectivity advantages of network-based bridging. >

Towards the information superhighway

Ultimately the USA will have a universal broadband network (UBN). This report summarizes and comments on Bruce Egan's recent book, Information Superhighways, which addresses transitional problems. First, we need to know the extent to which consumers would value a UBN network. Who should bear the risks associated with massive infrastructure investments? Next, there are questions about whether demand-pull technological progress is also expected to reduce costs in the long run and to improve quality of service. Egan reminds us that some stakeholders will gain and some will lose during the 1990s. The regulatory policies adopted in the coming years will influence the pace and pattern of investment in advanced public communication networks in the USA. Egan argues that it is important that policy discourage fragmentation within the network.

BERKOM: The first broadband isdn exchange and transmission system in Berlin

BERKOM: The first broadband isdn exchange and transmission system in Berlin

Evolution of ISDN towards broadband ISDN

Worldwide activities to evolve integrated services digital network (ISDN) into an optical-fiber-based universal broadband network have resulted in the first baseline documents, such as CCITT Recommendation I.121. The asynchronous transfer mode has been established as a key element of broadband ISDN (BISDN). The adoption of the G.707-709 recommendations on the new digital transmission hierarchy will also strongly influence further BISDN development. The author presents the current state of the BISDN discussion, especially within CCITT, briefly addressing broadband services and then concentrating on the user-network interface, as its definition is of utmost importance with respect to the introduction of a worldwide unique BISDN. Network scenarios and evolution and interworking aspects of the arising broadband realizations are also addressed. >