| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 112-117 |
| Abstraksi Narasi | : | The rapid evolution of mobile wireless access networks toward multimedia support with QoS provision forces the development of advanced wireless broadband systems with high reliability and high data rate. To achieve this goal, new system design concepts with increased system capacity will be required. In that context, ATM is becoming a major infrastructure, receiving a lot of attention for telecommunication system since ATM networks can most effectively support wireless access systems. Wireless ATM systems have low transmission cost, flexible functionality, mobile ATM protocol, and radio access layer protocols. This article overviews the various wireless broadband system studied at 5, 19.37, 40, and 60 GHz by European Union funded projects within the ACTS program. Moreover, related standardization activities and network evolution are also addressed. |
| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 46-50 |
| Abstraksi Narasi | : | The current deployment status of WDM systems in European telco operator networks is investigated and the underlying business case for these deployments examined. The different technical soutions beings proffered by suppliers and the inter-working of the SDH and WDM transport layers is discussed. Finally, the future path to WDM networking and WDM metropolitan solutions in the 1998-1999 timeframe is identified. |
| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 62-66 |
| Abstraksi Narasi | : | WDM technology is now being applied to international undersea fiber optic cable networks in order to provide enhancements such as increased network capacity and greater network flexibility. This article looks at what WDM technology can provide, the progress being made, and the special challenges in its application in undersea networks. We then describe several international undersea networks that, when complete by the end of 1999, will use WDM technology and will serve as a major part of the global undersea fiber optic infrastructure conecting the world. |
| Nama Pengarang | : | Robert Arnott et al, Patrick R. Trischitta, William C. Marra, Ewart Lowe, Jouni Mikkonen et al, Alexander Guntsch et al, Ermanno Berruto et al, John Charles Francis, Holger Herbrig, Nigel Jefferies, Alistair Munro et al, Alan McGuire, Paul Bonenfant, Robert K. Butler, David R. Polson, Patricia V. Hatton, Frank Cheston, John P. Ryan |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 96-102 |
| Abstraksi Narasi | : | The authors present an overview of advances in three areas including software radio, adaptive antenna technology, and high-temperature superconductivity as currently envisioned for use in advance cellular base stations. The conclusion broadly drawn is that the advancement in DSP and ASIC technologies will make the major contribution in making technically and commercially realistic. |
| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 32-35 |
| Abstraksi Narasi | : | The principal object of this article is to highlight the changes to lifestyle, culture, society, and architecture emerging or likely to emerge as a direct result of development in communications technology. Its secondary objective is to provoke discussion and a little healthy dissent in the academic community. The methodology employed is of the reflective phenomenological paradigm; reading and broad personal observations have formed the basis for trend identification and critical reflection which provide the main thrust of the article. The definition of literacy must be revised to embrace the new technologies, and the definition of creativity must emphasize synthesis at the expense of genesis. Of particular concern is the erosion of sultures and languages. The author argues that far from promoting democracy and enfranchising the general populace, technology effectively undermines the basis of democracy by the creation of an information underclass. This class will have the right and means to take part in the democratic process process but will lack the information necessary for the decision-making process. Far from introducing an electronic agora, technology is moving societies toward a form of Jeffersonian democracy in which property rights will take precendence over human rights. McLuhan`s global village is critically examined against the emerging reality and the author concludes that the global village is unachievable in the medium term, partly for technical reason and partly for social reasons. The communications revolution is not a liberating experience for most people; instead, life has come to be measured in seconds, with a corresponding loss of longer-term focus and sense of place. The author concludes that steps must be taken to preserve the quality of the media and the standard of its content; these are unlikely to arise from the `connected masses` and can only come from organizations and governments. The right to freedom of speech does not imply the right to be heard. Some controls must be enforced on the Internet to ensure the survival of art culture, and national identity. Perhaps most contentious is the view that those most closely involved with the development of the technology should take some responsibility for their creation. Convergence in media is resulting in collisions in society at large. Finally, McLuhan`s statement `The medium is the message` is examined and found wanting: the medium is not the message any more than the marketing is the product. |
| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 88-93 |
| Abstraksi Narasi | : | The services to be supported by an asynchronous transfer mode (ATM)-based multiservice network differ significalty in terms of their traffic characteristic and rewuired quality of service. During the last few years it has been broadly accepted that efficient use of transmission capacity is not possible unless these differences are reflected in the way the related traffic streams are handle within the ATM layer. To address this need, the ATM Forum and ITU-T [1, 3] have specified different real-time and non-real-time ATM-layer service categories. This article first discusses the requirements for traffic management in switch supporting all these service categories from the service providers` and users` points of view. The first generation of ATM switches, typically equipped with small cell buffers, only satisfies the requirements for the real-time service categories (CBR, rt-VBR). Statistical multiplexing, if supported at all, is limited to connections with low peak cell rates. Larger cell buffers and new traffic control functions are required to support non-real-time service categories (nrt-VBR, ABR, UBR). In the second part of this article a switch architecture which is scalable from small to large system sizes is presented. It provides the required buffering and additional functions for the non-real-time service categories with the aid of a statistical multiplexing unit (SMU), a module which can also be used as an optional addition to a conventional ATM switch. The focus is on the functional description of two novel yet key components of the SMU, namely the buffer management and cell scheduling functions. The buffer management function provides per-VC queuing and achieves an optimal utilization of the large cell buffer shared by connections of different service categories. The two-stage cell scheduling function supports traffic shaping on the VC and VP levels, and Wieghted Fair Queuing within groups of connections. The overall concept supports high link utilization, fairness, and throughput guarantees, and enables a migration from today`s ATM networks to a fully integrated multiservice network. Finally, implementation aspects are discussed to show the feasibility of the concept for very high bit rates. |
| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 82-86 |
| Abstraksi Narasi | : | The explosive growth of the Internet has given IP routing new challenges. Innovative solutions have recently been proposed to solve the current router bottleneck by evolving to a tighter integration of IP and ATM, an approach called shortcut routing. This article categorizes the current IP over ATM shortcut proposals and identifies a number of issues. However, while IP and ATM routing and forwarding fucntions must be more closely integrated, a differentiation according to type of traffic seems advangeous; hence the need to evolve to an IP over ATM dual-mode routing model. |
| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 42-48 |
| Abstraksi Narasi | : | This article proposes network solutions to the congestion on the PSTN caused by residential Internet and online subscribers in North America. The conflicts caused by Internet traffic on the PSTN are network problems and the impact of this traffic-from origination to termination-must be understood and addressed. To develop anunderstanding of Internet traffic, the data from traffic studies performed by two LECs was gathered and analyzed, and the observed traffic was characterized. This traffic characterized, combine with a knowledge of the increasing number of residential Internet subscribers to be estimated. The network solutions presented and discussed below were developed to address these impact. The Internet traffic observed from usage studies can be characterized by very long holding times and, in some cases, very high numbers of call overflows (calls routed to busy tone), especially late in the evenings. These unusual patterns cause the overall switch traffic to increase, but at the switch sub-component level their effects can be more serious. Telephone operators faced with high penetrations of Internet subscribers can expect to support the cost of additional trunking equipment, additional line equipment, and continuous equipment regrading and load balancing, as well as the risk of denying or degrading service to end users. Traditional solutions, although well understood, are reactive in nature; but for low penetrations of Internet users, they provide low-risk solutions. This article proposes nontraditional network solutions which introduce new functionality into network. Not only do these solutions relieve all network congestion, they also allow the LEC to offer new services while evolving the network to meet future demands. The initial effort to establish a new network architecture and a new service can be considerable, but for LECs facing large penetrations of Internet subscribers, such innovative network solutions are the key to network profitability. |
| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 94-102 |
| Abstraksi Narasi | : | Network support for multicast has triggered the development of group communication applications such as multipoint data dissemination and multiparty conferencing tools. To support these applications, several multicast transport protocols have been proposed and implemented. Multicast transport protocols have been an area of active research for the past couple of years. This document tries to summarize the activities in this work-in-progress area by surveying multicast transport protocols. The article also presents a taxonomy to classify the surveyed protocols according to several distinct features, discusses the rationale behind the protocols` design decisions, and present some current reasearch issues in multicast protocol design. |
| Nama Pengarang | : | - |
| Nama Majalah/Jurnal | : | IEEE Communications Magazine |
| Volume / Nomor Edisi | : | - |
| Nomor Halaman | : | 104-109 |
| Abstraksi Narasi | : | Locating mobile objects in a worldwide system reauires a scalable location service. An object can be a telephone or a notebook computer, but also a software or data object, such as a file or an electronic document. Our service strictly separates an objects`s name from the addresses where it can be contacted. This is done by introducing a location-independent object handle. An object`s name is bound to its unique object handle, which, in turn, is mapped to the addresses where the object can be contacted. To locate an object, we need only its object handle. We present a scalable location service based on a worldwide distributed search tree that adapts dynamically to an object`s migration pattern to optimize lookups and updates. |
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