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Most existing network communication systems, such as the Internet, are built around the TCP/IP protocol stack. However, TCP/IP cannot effectively support the upcoming network communication systems with more wireless communication links and higher requirements in terms of throughput, latency, and reliability. In this article, we introduce a general network communication protocol design based on batched network coding (BNC), which includes the existing framework as a special case and whose design can be guided by channel coding theory. BNC-based protocols can have significant throughput gain for single-hop or multihop wireless communications and provide better trade-off among throughput, latency and reliability. [ABSTRACT FROM AUTHOR]

Real-world robot networks create hostile radio environments due to their highly dynamic communication topologies and stringent real-time transmission requirements. In this article, we propose improvements to contention-based networks that utilize inter-robot navigation information for safer robot motion control in dense multi-robot settings. Toward this end, we introduce a Crash Risk Prioritization (CRP) index, which is employed as the core metric in a scheme of dynamic beacon rate control. Key to our approach is a coupled evaluation setup that allows us to evaluate the impact of network-level changes on the safety of robot navigation. Our results demonstrate that the co-design and simulation of robotic control algorithms and network protocols provide key insights and metrics into the network-level requirements for V2V systems. These insights allow us to make informed conclusions about how such networks can be best served by emerging standards. [ABSTRACT FROM AUTHOR]

This article discusses novel approaches to improve energy efficiency of different optical access technologies, including time division multiplexing passive optical network (TDM-PON), time and wavelength division multiplexing PON (TWDM-PON), point-to-point (PTP) access network, wavelength division multiplexing PON (WDM-PON), and orthogonal frequency division multiple access PON (OFDMA-PON). These approaches include cyclic sleep mode, energy-efficient bit interleaving protocol, power reduction at component level, or frequency band selection. Depending on the target optical access technology, one or a combination of different approaches can be applied. [ABSTRACT FROM PUBLISHER]

Smart homes and environments will consist of a large number of low power wireless devices such as sensors and actuators. Recently IETF standardized a network protocol called RPL that is designed to run on these nodes. In this article, we study the performance of RPL on a variety of scenarios that these nodes will encounter when they are deployed in practice. We deploy a network of 23 sensor nodes in a computer lab to monitor energy used by each computer across the applications and users. We subject the network to four different levels of interference that are representative of the types and levels of interference that these networks might encounter in deployment. Our study finds that RPL?s reliability degrades even with an access point in overlapping channel under normal network traffic. With high interference, the packet delivery reliability goes down to 10 percent. The scenario that resulted in this performance is not unimaginable in smart home or environment. This performance degradation is partly due to lack of coordination across the layers of the protocol stack: RPL is unaware of the changes in the wireless environment underneath and proceeds as usual. As other research has shown, coordination across the network stack is essential for network protocols to work reliably in the presence of interference. This will require a more coordinated approach to standards across the bodies. [ABSTRACT FROM PUBLISHER]

Policy-based management allows the deployment of networks offering quality services in environments beyond the reach of real-time human control. A policy-based protocol stack middleware, the context-aware broker, has been developed by the authors to autonomically manage the remote deep space network. In this article example policy rules demonstrate the concept, and prototype results from ns-2.30 show the overall positive costbenefit impact in an example scenario. [ABSTRACT FROM AUTHOR]

The IP multimedia subsystem defined by the Third Generation Partnership Project is the architecture merging the Internet and telecom worlds. The IMS was designed to make it easy for third-party developers to make their applications available to all IMS users, and by doing so provide more than only the basic telecom services like voice, messaging, presence and contact management. However, good knowledge of the IMS network architecture and the underlying Internet protocols is still needed to develop IMS applications. In addition, telecom expertise is needed to deploy the application and provision users. To ease the development and deployment process, it is essential to provide application developers with APIs and similar tools available for Web 2.0 application development today. In this article we explore the architectural and protocol aspects that enable third-party IMS application development and deployment. We also study how the applications will coexist with other applications already deployed in the IMS. Moreover, we describe Java libraries exploiting the functionality of the IMS both in the terminal client and within the core network. We also show how these Java libraries can be used for developing and deploying new applications in an IMS testbed, which provides IMS functionality over commercial 3G networks. [ABSTRACT FROM AUTHOR]

Modeling and simulation methods are employed by scientists and engineers to gain insight into system behavior that can lead to faster product time-to-market and more robust designs. These advantages come at the cost of model development time and the potential for questionable results because the model represents limited attributes of the actual system. M&S techniques are used to characterize complex interactions and performance at various layers of the protocol stack. This article provides a discussion of M&S for wireless network designers and developers, with particular attention paid to the architectural issues, as well as a discussion of the various communication M&S tools available today. The topics presented span the protocol stack, including radio-frequency-propagation M&S tools, physical-layer and waveform M&S, network-layer M&S, and distributed simulation, as well as waveform generation for test and evaluation. [ABSTRACT FROM AUTHOR]

This article investigates distributed cooperative medium access control protocol design for multihop wireless networks. Cooperative communication has been proposed recently as an effective way to mitigate channel impairments. With cooperation, single-antenna mobile terminals in a multi-user environment share antennas from other mobiles to generate a virtual multiple-antenna system that achieves more reliable communication with a higher diversity gain. However, more mobiles conscribed for one communication inevitably induces complex medium access interactions, especially in multihop wireless ad hoc networks. To improve the network throughput and diversity gain simultaneously, we investigate the issues and challenges in designing an efficient MAC scheme for such networks. Furthermore, based on the IEEE 802.11 DCF, a cross-layer designed cooperative MAC protocol is proposed. The MAC scheme adapts to the channel condition and payload length. [ABSTRACT FROM AUTHOR]

Recent studies demonstrated that dynamic spectrum access can improve spectrum utilization significantly by allowing secondary unlicensed users to dynamically share the spectrum that is not used by the primary licensed users. Cognitive radio was proposed to promote the spectrum utilization by opportunistically exploiting the existence of spectrum "holes." Meanwhile, cooperative relay technology is regarded widely as a key technology for increasing transmission diversity gain in various types of wireless networks, including cognitive radio networks. In this article, we first give a brief overview of the envisioned applications of: cooperative relay technology to CRNs, cooperative transmission of primary traffic by secondary users, cooperative transmission between secondary nodes to improve spatial diversity, and cooperative relay between secondary nodes to improve spectrum diversity. As the latter is a new direction, in this article we focus on this scenario and investigate a simple wireless network, where a spectrum-rich node is selected as the relay node to improve the performance between the source and the destination. With the introduction of cooperative relay, many unique problems should be considered, especially the issue for relay selection and spectrum allocation. To demonstrate the feasibility and performance of cooperative relay for cognitive radio, a new MAC protocol was proposed and implemented in a universal software radio peripheral-based testbed. Experimental results show that the throughput of the whole system is greatly increased by exploiting the benefit of cooperative relay. [ABSTRACT FROM AUTHOR]

Cooperative networking, by leveraging the broadcast nature of the wireless channel, significantly improves system performance and constitutes a promising technology for next-generation wireless networks. Although there is a large body of literature on cooperative communications, most of the work is limited to theoretical or simulation studies. To impact the next generation of wireless technologies and standards, it is essential to demonstrate that cooperative techniques indeed work in practice. This article describes two programmable cooperative communication testbeds built at Polytechnic Institute of NYU to achieve this goal. The testbeds are based on open- source platforms and enable implementation of cooperative networking protocols in both the physical and the medium access control layer. Extensive experiments carried out using the testbeds suggest not only that cooperative communication techniques can be integrated into current wireless technologies, but also that significant benefits of cooperation can be observed in terms of network throughput, delay, and video quality in real applications. [ABSTRACT FROM AUTHOR]

As Ethernet traffic increases rapidly in carrier networks, service providers have an increasing need for Ethernet infrastructure networking in order to scale their Ethernet services. Ethernet infrastructure transports Ethernet traffic over distance, protects the traffic from link and nodal failures, and aggregates Ethernet connections from a large number of low-speed ports onto a much smaller number of high-speed ports. An Ethernet infrastructure allows service providers to inexpensively interconnect end user locations with one another for private line services, and to interconnect end users with the VPLS and IP/MPLS service edges for enterprise, residential, and mobility services. OAM and protection capabilities are critical to enable Ethernet to be deployed as an infrastructure technology. This article reviews several important developments in Ethernet OAM and protection standards, and discusses how those capabilities are vital for the creation of an effective Ethernet infrastructure. [ABSTRACT FROM AUTHOR]

In this article, a novel network architecture called resilient burst ring is proposed to implement the next-generation WDM-supported ultrahigh-speed (100 gigabit or higher) carrier Ethernet. This architecture inherits all the best features of resilient packet ring (IEEE 802.17), provides a burst-mode data transmission scheme through a two-sublayer (optical and electronic) hierarchy, and realizes the WDM-supported ultra-high-speed Ethernet with scalability and reliability. RBR adopts a two-layer buffering scheme to resolve the contentions of optical burst packets and provides three different data transmission modes. With the proposed PriorityOnly-Destination-Delay resource reservation control protocol, RBR can provide a flexible Q0S strategy to implement the transmission of all of the applications and services in existing networks. [ABSTRACT FROM AUTHOR]

Advances in next-generation SONET/SDH have introduced novel features for generic protocol framing/encapsulation, virtual concatenation, inverse multiplexing, dynamic circuit adjustment, and so on. In turn, these provisions have enabled much improved multi-tiered service provisioning and are viewed very favorably by carriers, particularly incumbents. This article looks at this evolved framework with a particular focus on value-added services creation. Results from a sample performance evaluation study also are presented to quantify some of the achievable gains. [ABSTRACT FROM AUTHOR]

Research on vehicular ad hoc networks has focused mainly on efficient routing protocol design under conditions where there are relatively large numbers of closely spaced vehicles. These routing protocols are designed principally for urban areas with high node density and fully connected networks and are not suitable for packet delivery in a sparse, partially connected VANET. In this article, we examine the challenges of VANETs in sparse network conditions, review alternatives including epidemic routing, and propose a border node-based routing protocol for partially connected VANETs. The BBR protocol can tolerate network partition due to low node density and high node mobility. The performance of epidemic routing and BBR are evaluated with a geographic and traffic information-based mobility model that captures typical highway conditions. The simulation results show that under rural network conditions, a limited flooding protocol such as BBR performs well and offers the advantage of not relying on a location service required by other protocols proposed for VANETs. [ABSTRACT FROM AUTHOR]

Much progress can be observed in the domain of Vehicular Ad Hoc Network (VANET) research looking back at the last decade. It can be seen that studies of vehicular communication protocols in the context of VANETs are typically based on simulation models. This approach has two major prerequisites: First, detailed network simulation of all layers of communication protocols is necessary as provided by a wide variety of tools by the networking community. Secondly, realistic simulation of vehicles' mobility, i.e., an exact modeling of road traffic, is needed to estimate positions and movements of involved components. The contributions of this article are twofold: First, a survey of the evolution of mobility modeling in VANET simulations is provided, outlining the simulation strategies typically used. Secondly, this article investigates how recent advances in bidirectional coupling of road traffic microsimulation and network simulation lead to more realistic results at comparably low computational cost. In conclusion, this article advocates to employ such techniques that are openly available for further studies of new communication protocols and mechanisms in the domain of VANET research. [ABSTRACT FROM AUTHOR]

IEEE 802.15.4 is the global standard protocol designed for low-power and low-rate wireless personal area networks. When applied to sensor networks, extra care should be taken due to their requirements for multihop communication with minimum energy consumption. In this article we first discuss potential problems with the energy consumption in sensor networks using IEEE 802.15.4. Then six representative categories of algorithms are presented. The algorithms reside in between the MAC and a network layer. All operations of the MAC are performed through the standard interfaces of IEEE 802.15.4 without altering the standard protocol. The energy consumption and latency of the algorithms are evaluated by analysis and experiments, and the feasibility of real implementations is also discussed. [ABSTRACT FROM AUTHOR]

This article describes the intercarrier external network-to-network interface development challenges at the Kei-han-na Info-Communications Open Laboratory. The E-NNI prototype that was developed provides interworking functionality between the automatically switched optical network control plane function of the ITU-T and the generalized multiprotocol label-switching control plane function of the IETF. In this article, an analysis of the differences between ASON network technologies and GMPLS network technologies, a detailed signaling protocol and routing protocol interworking mechanism, and the interworking experimental results of nationwide ASON and GMPLS network domains are described. [ABSTRACT FROM AUTHOR]

Covert channels are used for the secret transfer of information. Encryption only protects communication from being decoded by unauthorized parties, whereas covert channels aim to hide the very existence of the communication. Initially, covert channels were identified as a security threat on monolithic systems such as mainframes. More recently, focus has shifted toward covert channels in computer network protocols. The huge amount of data and large number of different protocols in the Internet is ideal as a high-bandwidth vehicle for covert communication. This article provides an overview of the existing techniques for creating covert channels in widely deployed network protocols, and common methods for their detection, elimination, and capacity limitation. [ABSTRACT FROM AUTHOR]

In this article we study two representative mobility management schemes for mobile hotspots with heterogeneous multihop wireless links: the NEMO basic support protocol at the network layer and the SIP-based network mobility support protocol at the application layer. We evaluate their salient features and quantify their handoff latency. It is shown that the SIP-based network mobility support protocol can easily be deployed and reduce the tunneling overhead incurred in the NEMO basic support protocol. However, it increases handoff latency due to longer message length. We also discuss several open research issues for seamless mobility support in mobile hotspots. [ABSTRACT FROM AUTHOR]

After around a decade of active research on wireless sensor networks, recent standards released are stimulating the development of commercial products. One of these standards is ZigBee. This article highlights some of the lessons from the field that went into the standard. It also describes the ecosystem emerging around Zigbee, and the enabling trends in that ecosystem. New areas of activity in the ZigBee standards body are highlighted as well. [ABSTRACT FROM AUTHOR]

The present view of medical environments, where isolated networks are used for IT and medical applications, is changing toward an integrated heterogeneous network scenario that can support a wide range of applications. WPAN and WLAN technologies will play a fundamental role in enabling such integrated environment that is expected to support both medical and nonmedical applications. The ultimate goal is to exploit WPAN and WLAN technologies, as well as other wireless networks, such as 3G cellular systems and satellite networks, to support highly efficient medical care delivery, anytime and anywhere. However, the life-critical nature of some medical applications imposes additional challenges that have not been considered in nonmedical scenarios. This article discusses some future scenarios where WLAN and WPAN technologies can be used to provide an integrated and ubiquitous network in medical environments, and identifies the main issues to be addressed in order to meet the QoS requirements of different medical applications when operating in integrated environment. [ABSTRACT FROM AUTHOR]

With the Information Age in full and rapid development, users are becoming accustomed to having immediate access to information. Users demand more capabilities from every kind of electronic device: more processing power, more features, and better connectivity. Users are also realizing the benefits of collaborating with others in their communities to help expand the body of knowledge. One user that understands the benefits of information sharing is the United States Department of Defense. The DoD's Network-Centric Enterprise Services initiative, along with the concept of pushing the ‘power to the edge,’ aims to enable end users with maximum situational awareness and the most comprehensive battlespace, all in a secure networking environment. Providing so much data and capabilities to the end user, however, will require an increase in communications capability and efficiency. To address increased capability needs, the DoD is continually developing and enhancing the Global Information Grid (GIG) throughout its various ‘layers’ of communication infrastructure. One such layer of infrastructure involves the use of cooperative low Earth orbiting satellites for efficient multicasting communications. In this article we review the network-centric concept and the GIG infrastructure. We then discuss the potential benefits to adding a low Earth orbit satellite communications infrastructure to the GIG model. Finally, we show how multicasting protocols can enhance the efficiency within the GIG and reduce some of the long-haul communications burdens. [ABSTRACT FROM AUTHOR]

This article reports the latest results of an R&D effort to develop a prototype implementation of a dynamic policy-based network management (PBNM) system that can be used to configure and manage a secure network for a coalition environment across an unsecured wide area network. The prototype, based on a distributed architecture, includes capabilities for policy creation and management, dynamic policy negotiation, and dynamic policy provisioning. The policy negotiation facilitates the rapid deployment of a coalition network while the dynamic policy provisioning automates the configuration and management of network services including firewalls, virtual private network connections, routing, quality of service (QoS), and domain name services. Such a PBNM system enhances an organization's ability to react to network incidents identified by a network situational awareness assessment. Although the focus of the current research is a military coalition environment, the system can be used in any distributed enterprise or collaborative environment. [ABSTRACT FROM AUTHOR]

Wireless sensor networks are proposed to deliver in situ observations at low cost over long periods of time. Among numerous challenges faced while designing WSNs and protocols, maintaining connectivity and maximizing the network lifetime stand out as critical considerations. Mobile platforms equipped with communication devices can be leveraged to overcome these two problems. In this article existing proposals that use mobility in WSNs are summarized. Furthermore, a new approach to compute mobile platform trajectories is introduced. These solutions are also compared considering various metrics and design goals. [ABSTRACT FROM AUTHOR]

The RapidlO data-stréaming logical layer provides a segmentation and reassembly service to higher layers. Since a RapidlO receiver can potentially receive 64-kbyte PDUs from 64-kbyte senders, the memory requirements for successfully reassembling fragments is huge (∼4 Gbytes). As RapidlO-based hardware chips have limited memory, efficient arbitration algorithms/protocols are needed that can fairly share memory among competing traffic streams, under constraints imposed by the standard. In this article we show that absence of proper arbitration can lead to deadlocks and system underutilization. We then develop a Flow Arbitration Protocol (now a part of RapidlO 2.0) as an extension to existing specification. A defining characteristic of this protocol is that memory resources can be reserved for single- and multi-PDU transfers. [ABSTRACT FROM AUTHOR]

Wireless mesh networks (WMNs) have emerged as a key technology for next-generation wireless networking. Because of their advantages over other wireless networks, WMNs are undergoing rapid progress and inspiring numerous applications. However, many technical issues still exist in this field. In order to provide a better understanding of the research challenges of WMNs, this article presents a detailed investigation of current state-of-the-art protocols and algorithms for WMNs. Open research issues in all protocol layers are also discussed, with an objective to spark new research interests in this field. [ABSTRACT FROM AUTHOR]

This article presents a brief overview, state of the art, and taxonomy of optical WDM testbeds, and outlines the differences between them and the ADRENALINE testbed. ADRENALINE is an optical circuit-switched WDM testbed that deploys reconfigurable OADMs based on various technologies (e.g., AWO and tunable lasers). In ADRENALINE, end-to-end lightpaths are set up and torn down dynamically and in real time by means of a GMPLS-based control plane (switched connections) and a distributed management plane (soft-permanent connections). ADRENALINE supports the request of SPCs under user initiative by combining GMPLS, SNMP, and XML. ADRENALINE allows both the topology and major characteristics of the data communications network to be modified, enabling control and management related experiments with varying DCN. In our experiments we investigate user management of lightpaths and address its performance in terms of basic SLA parameters related to connection establishment (delay and availability). Finally, we address remaining challenges and outline exciting avenues of future work on ADRENALINE. [ABSTRACT FROM AUTHOR]

New York City Transit's subway system is one of the largest and most complex mass transportation systems in the world. Because of the extensive subway system, an extensive communications network infrastructure is needed to allow for communications of the various subway services with the control centers to support mission-critical (and safety-critical) applications. The current network utilizes multilayer network technologies, including SONET, ATM, and IP (layer 2/3 device) layer networks. As a consequence of using these various technologies, extensive challenges are faced in trying to consolidate these separate networks into a single management view, simplifying (and automating) not only the provisioning aspects but also troubleshooting/ fault management aspects of the network. Such automation will help to simplify network operations and allow for better handling and management of the reliability and availability of the network. To achieve this goal, various technologies were evaluated. Consideration is being given to multiprotocol label switching technology. MPLS offers the potential to help converge to a simpler networking model. In order to achieve this, certain capabilities must be available (e.g., the ability to quickly and automatically identify defects/failures and subsequently reroute around these failures). This article discusses the operational requirements for the MPLS network from the point of view of backbone networks that support a mass transportation system operator. [ABSTRACT FROM AUTHOR]

The recent advent of converging the IP and optical networks has necessitated the development of a generalized multiprotocol label switch-in framework. Resilience becomes more important than ever before in a GMPLS network since a single cut of an optical fiber may generate hundreds of link and node failures at high layers of the GMPLS architecture. In this article we briefly survey the current work regarding GMPLS recovery management, and present a new resilience-based dynamic GMPLS path management strategy. We present a simple model to represent the resilience requirements in GMPLS path management, and propose fast path management algorithms. The salient feature of the proposed approach is that it enables the paths to be dynamically selected under multiple simultaneous failure occurrences while satisfying the resilience requirement. Backup path design rules are developed, and the condition for backup path availability is derived for the special mesh-type GMPLS network. Finally, a simple example is shown to illustrate the effectiveness of the proposed resilience model and path management mechanism. [ABSTRACT FROM AUTHOR]

We present an overview of scalable admission control in IP networks. We introduce various approaches and discuss the mechanism and characteristics of each method. In particular, we argue that end-to-end measurement based admission control (EMBAC), which employs end-to-end on-demand probing, should be used for call admission control. Second, we consider use of EMBAC in VoIP networks. We present a new probability-based EMBAC scheme and show that its performance is close to the ideal method using virtual-trunk-based admission control. We also present a QoS allocation approach for selecting an admission threshold and dimensioning link capacities. A simple network design and evaluation results suggest that this QoS allocation approach is effective to adequately dimension a network, while satisfying end-to-end targets in terms of blocking probability and packet loss rate. [ABSTRACT FROM AUTHOR]

The emerging next-generation networking environment presents an IP-based core interconnecting many wireless radio access networks, providing ubiquitous access to end users through a vast variety of wireless devices. Although the IP protocol will be the common denominator, the new environment brings together many different interconnecting domains, each following different QoS models, complicating the overall end-to-end QoS process. This article discusses the need to standardize an end-to-end QoS protocol. It does not, however, focus on the signaling mechanism, since there is currently a relevant ongoing activity in IETF. Instead, it concentrates on the formulation of the QoS information describing the QoS requirements of the session to be established. It presents the Generic Service Specification Framework that not only enables the QoS requirements of a specific session to be captured (like a generic QoS template), but also the QoS classes of each IP domain can be described according to it. Through the systematic specification of a domain's QoS classes, an intelligent automatic mapping algorithm can be applied during an end-to-end QoS request, in order to select the most appropriate service class in each domain, as well as to extract the required traffic-related parameters to perform traffic con- trol operations, such as admission control, policing, and scheduling. [ABSTRACT FROM AUTHOR]

Next-generation wireless systems should provide to the user access to a broad range of services in a transparent way, independent of user location by making the technology invisible and embedded in the natural surroundings. Reaching this goal requires efficient cooperation between heterogeneous networking technologies and different protocols. Wireless personal networks are an integral part of such an emerging heterogeneous infrastructure. It is highly desirable, and in fact required due to economical constraints, to incorporate the present wireless systems in building the new paradigm. The key "protocol glue" between systems is the use of IP. Based on this scenario, we describe an architecture suited for the present and future personal mobile communications networks and services. [ABSTRACT FROM AUTHOR]

This article presents the deployment and test of IPv6 services in the very high broadband IP/WDM (VTHD) [1] network for new-generation Internet applications. The VTHD project is partially funded by the French government through the French Research Network for Telecom (RNRT). VTHD supports both IPv4 and IPv6 services, and interconnects research centers and institutions in France. It has a public autonomous system number (AS20603) and a public IPv6 subnet. It is connected to the IEv6 global network via Open Transit (France Telecom's international IP service for ISPs). VTHD in France compares with Internet2 in the United States. This article focuses on the implementation of the lPv6 service, IPv6 performance (in the context of a high-speed network), the advantages of given technologies, and problems encountered. The following items are developed: • VTHD architecture • IPv6 address space and aggregation • Transition mechanisms • Routing protocols • Network test performance • IPSec est performance • Naming (DNS) • Network management [ABSTRACT FROM AUTHOR]

Analyzes pros and cons of providing Internet protocol (IP) multimedia session control capabilities of real-time IP multimedia services in universal mobile telecommunication system (UTMS), as opposed to just providing basic IP connectivity, as of November 3, 2003. Overview of IP multimedia services; Overview of the general packet radio services architecture; Advantages and disadvantages of providing only basic IP connectivity; Concepts of IP multimedia subsystems; Overview of control signaling for wireless-to-wireless session setup. INSET: UMTS RELEASES..

Discusses the management of mobile communications in third-generation (3G) wireless Internet Protocol (IP) computer networks. Universal Mobile Telecommunications System; Deployment of IP and Multiprotocol Label Switching; 3G all-IP network models; Micromobility protocol; Issues of fast handoff, scalability, efficiency, quality of service, reliability and gradual deployment.

Investigates to which extent switched connections and fast connection provisioning can be used to provide resilience in an Internet Protocol-over-optical multilayer network scenario. Static multilayer resilience schemes; Dynamic multilayer resilience schemes in intelligent optical networks (ION); Comparison between ION global and local reconfiguration.

Presents a concept for a system beyond third-generation mobile radio systems, which comprises a combination of several optimized access systems in a common Internet Protocol-based medium access and core network platform. Insight on the development of mobile radio systems; Trends in mobile communications; Characteristics of a system beyond third-generation mobile radio communications.

Presents information on a study which described the motives underlying the deployment of wavelength-division multiplexing (WDM) technology in the long-haul and short-haul areas of GTS' operational transport network. Design of synchronous digital hierarchy-over-WDM and Internet Protocol-over-WDM networks; Application of WDM in GTS' Pan-European transport network; Future operational and management requirements of WDM network.

Compares Internet Protocol routing and Multiprotocol Label Switching (MPLS) approaches in telecommunications network. Value of MPLS to networking; Discussion on the advantages and disadvantages of the two approaches to telecommunications network.

Presents a study which introduced a set of control mechanisms of a protocol architecture to support MPEG-2-based communications systems using asynchronous transfer mode (ATM) networks. Use of hierarchical coding scheme; Mechanisms in ATM switches; Algorithm on dynamic error concealment; Conclusions.

Presents information on a study which stated that the Internet Protocol provides infrastructure for multimedia and communications applications by using voice, video and data. Impact of Internet applications on electronic commerce; Importance of call center to customer services of companies.

Presents information on the standards of organizations which focus on Internet protocol (IP) and telecommunication integration. Description of the outlines of IP-related organizations; Information on the IP-related activities in International Telecommunication Union-Telecommunication Standardization Sector (ITU-U); Standards of the organizations and ITU-U recommendations; Collaborative relationship of the organizations. INSET: Related Web Sites.

Presents an overview of the interworking aspects for the provision of interoperable services between Internet protocol (IT) Telephony and public switched telephone network (PSTN) voice services. Interworking function in five basic voice communications scenarios; Signaling and control protocols; User data transfer; Problems that still need to be solved.

The process of migrating voice and video traffic onto a common infrastructure, using Internet Protocol (IP) as the base protocol, is gathering speed. The route toward service integration using Internet technology is inevitable for several reasons, among them are reduction of operating expenses, optimizing operating efficiency, better utilization of the trunks, improving the flexibility of new telephony and multimedia services, the fast pace of new interactive service development, evolving voice beyond legacy telephony, the need to satisfy rapidly evolving customer expectations, the desire to increase service provider revenues. Being a connectionless packet-based technology, the Internet Protocol (IP) intrinsically lacks features that guarantee quality of service (QoS) and security. In addition, any attempt to migrate public switched telephone network services onto an IP network must not worsen QoS. Users would find this unacceptable, especially for telephony. Most available solutions for voice over IP telephony services tend to bypass QoS limitations by limiting coverage to specific areas in which network resources are overprovisioned.

Provides information on the development of telephony over Internet protocol (IP) in France. Trials being set in French research laboratories about IP; Standard bodies working on aspects of telephony over IP.

Deals with the first Internet Protocol-Telephony Workshop held on April 12 to 13, 2000 in Berlin, Germany. Issues discussed in the workshop; Highlights of the program; Information on the participants.