Showing papers on "10G-PON published in 1997"

Security issues in all-optical networks

Abstract: All-optical networks are emerging as a promising technology for terabit per second class communications. However, they are intrinsically different from electro-optical networks, particularly because they do not regenerate signals in the network. The characteristics of all-optical network components and architectures manifest new and still unstudied security vulnerabilities but also offer a new array of possible countermeasures. We focus on two types of attacks on the physical security of the network: service disruption, which prevents communication or degrades quality of service (QoS), and tapping, which compromises privacy by providing unauthorized users access to data which may be used for eavesdropping or traffic analysis.

Integrated optical ports

Abstract: An optical access system is shown for use in an office setting including a workstation providing for communication between a network and a computing device, the workstation having a worksurface and at least one network access point coupled to an optical network port. The computing device has a device access point coupled to an optical device port for direct optical communication with the optical network port. The optical access system includes an access station containing the optical network port so that the optical network port is selectively adjustable in a vertical direction by manually repositioning with respect to the computing device and the worksurface. Direct optical communication between the optical network port and the optical device port can be maintained notwithstanding the presence of objects that may obstruct direct optical communication. The optical access system may include a portable computer having a base and a covering lid to which the optical device port is mounted. A workstation providing for direct optical communication between a network and a computing device having a remote port is also disclosed. The workstation includes an article of furniture and an access station installed within the article of furniture providing at least one network access point and including a plurality of optical network ports. At least one network access point is coupled to the network and to each of the plurality of optical network port. The computing device is selectively adjustable in position relative to the article of furniture to establish a network connection within the workstation between the computing device and the network through the network access point by establishing direct optical communication between the remote port and at least one of the plurality of optical network ports.

Full service optical access networks: ATM transport on passive optical networks

Abstract: Multimedia communication has become the driving force for installing broadband systems in the public network. Different alternative solutions have been presented to realize a broadband interactive access network, such as installing optical fiber or upgrading the existing copper network with ADSL for twisted pair or hybrid fiber coax for CATV networks. Among these alternatives, optical fiber access networks are seen as the most future-safe solution. Especially, passive optical networks prove to be a cost-effective way to introduce fiber into the access network. This article presents ATM-based transport on passive optical networks, starting with a current implementation of an ATM-PON (APON) system that has already been installed for various trials. It further describes the evolution of APON systems to high-splitting, long-range PONs. The increase in both number of subscribers and distance range is discussed in combination with some specific technological issues such as upstream burst mode optical amplification. Special emphasis is placed on the work carried out within the scope of the ACTS PLANET project.

Inter-network interface for photonic transport networks and SDH transport networks

Abstract: To realize a really effective photonic transport network, we must develop the network node interface (NNI) structure and the inter-network interface (INI) for the WDM optical path transport network. This paper proposes the NNI structure for the WDM optical path transport network that is defined as the optical transport module (OTM), and proposes the INI structure between the optical path transport network and the SDH transport network. The proposed INI structure can be developed with minimum modification from the existing SDH line-terminal system. Therefore, the economical hardware development and the economical and smooth introduction of the WDM optical path transport network become possible.

Network topologies for SuperPON

Abstract: The generic architecture of a SuperPON (super passive optical network) with a target optical split of 2048 and a maximum range of 100 km. A bit rate of 2.5 Gbit/s is distributed to the optical network units (ONU) by time-division multiplexing (TDM) in the downstream direction, whereas a time-division multiple access (TDMA) protocol is used to share the 311-Mbit/s upstream bit rate. Optical repeater units (ORUs) are integrated in the network to compensate for the optical losses.

Network architecture for optical path transport networks

Abstract: This paper proposes a new layered transport network architecture on which the WDM optical path network can be effectively created. The optical path network will play a key role in the development of the transport network that will realize the bandwidth-abundant B-ISDN. This paper extends the layered transport network architecture described in ITU-T Recommendation G.803 which is applied in existing SDH networks. First, we elucidate an application example of WDM optical path networks. Next, we propose a new layered architecture for WDM-based transport networks that retains maximum commonality with the layered architectures developed for existing B-ISDN networks. The proposed architecture is composed of circuit layer networks, electrical path layer networks, optical layer networks, and physical media (fiber) networks. The optical layer is divided into an optical path layer and an optical section layer. The optical path layer accommodates electrical paths. Optical section layer networks are divided into optical multiplex section (OMS) layer networks and optical repeater section (ORS) layer networks. The OMS layer network is concerned with the end-to-end transfer of information between locations transferring or terminating optical paths, whereas the ORS layer is concerned with the transfer of information between individual optical repeaters. Finally, a detailed functional block model of WDM optical path networks, the function allocation of each layer, and an optical transport module (OTM) are developed.

Parallel optical links for gigabyte/s data communication

Abstract: Parallel optical interconnection technology can solve many of the current data bottlenecks that exist due to the ever growing Internet usage and the increasing speeds of processors. As a result many optoelectronic companies have begun to make parallel optical modules available with a variety of performances and costs. This paper will present an overview of the current work being done in this area.

Optical monitoring system for scalable all-optical networks

Abstract: High traffic and high capacity communications are believed to become cost-effective with the use of all-optical networks based on OFDM (optical frequency division multiplexing). In such networks, new strategies for OA and M (operation, administration and maintenance) functions need to be developed so as to suit the introduction of a new optical layer where in wavelength routing is exploited and faults are detected in a transparent manner. In this paper, we propose a scheme to monitor optical channels in the optical layer for supporting OA and M functions of a transparent and scalable photonic network.

Enhanced privacy in broadcast passive optical networks through the use of spectral slicing in waveguide grating routers

Abstract: We have measured the ability of a third party to intercept upstream messages in both passive splitter-based and waveguide-grating router-based broadcast passive optical networks. Bit-error-rate (BER) measurements at 150 Mb/s indicate that privacy is enhanced by at least 14 dB in the router-based network, and will improve further with router developments.

Optical switching system for MPP, LAN, or WAN systems

Abstract: Whether intended for use in massively parallel processing (MPP), local-area networking (LAN), or wide-area networking (WAN) systems, optical switching technology has not yet seen significant use in commercial practice. This paper presents the design of an optical switching system suitable for all of the above uses. The data path is all optical, with electrical-to-optical signal translation taking place only at the message source and optical-to-electrical signal translation taking place only at the destination. The control path, however, makes extensive use of electrical technology, using a unique control algorithm appropriate to the mixed-technology design. We refer to this dual (optical and electrical) design as the Gemini interconnection network.

A European multiwavelength optical network

Abstract: A number of research issues are considered in the study of an European multiwavelength optical network. The main part of the study is the design of an all-optical network to overlay the European national networks and link major centers therein. We survey most of the issues considered in this respect within the frame of two projects funded by the European Commission. Another part of the study focuses on the underlying European national networks and their possible development to interface with the proposed overlay. The main aim of this paper is to put together these two parts and oversee the prospect of an European ultra-high capacity multiwavelength optical infrastructure.

Impact on traffic and transmission performance of all-optical wavelength converters placed at the network interface or in OXCNs

Abstract: In summary, placing optical wavelength convertors (OWCs) in the optical cross connecting nodes (OXCN)s rather than at the fibre network interface not only improves the traffic performance but also enhances the performance of the physical layer, e.g., in terms of relaxed cross talk requirements.

Optical network research and development in European Community programs: from RACE to ACTS

Abstract: The European Union programs of cooperative research and development in telecommunications aim to ensure the realization of the future information society. The RACE Program (1988 to 1995) made an important contribution to the development of advanced optical communications. The current ACTS Program has an increased focus on field trials and networking. ACTS projects in the field of optical networks are studying multiwavelength network concepts, customer access, high-speed multiplexing and transport, and components and subsystems.

Enhanced privacy in broadcast passive optical networks through use of spectral slicing in waveguide grating routers

Abstract: Recently proposed wavelength-division multiplexed (WDM) passive optical network (PON) architectures utilize a waveguide-grating router (WGR) at the remote node to establish point-to-point or broadcast connections. While the initial push for WGR-based PONs was driven by the flexibility, privacy/security, and high capacity associated with point-to-point architectures, the advantages of providing broadcast delivery over these networks was also apparent. The WGR, when illuminated by a broadband source, mimics the broadcast function of a conventional passive splitter insofar as each output port receives approximately equal optical power.

High-capacity upgrade of a PON by means of wavelength-routers and WDM techniques

Abstract: A concept for an all-optical wavelength division multiplexing (WDM) overlay on a passive optical network (PON) and its experimental verification is presented. The WDM overlay at 1.5 /spl mu/m is realised leaving the outside fibre plant and the operation of the existing PON at 1.3 /spl mu/m unaltered. Arrayed waveguide gratings (AWG) are used to establish a point to point connectivity via individual wavelength paths between central office (CO) and each optical network unit (ONU). To keep the remote node (RN) totally passive the AWG at the RN can be monitored from the central office.

100-Gbit/s time-division multiplexed multi-access networks

Abstract: The trend toward higher bandwidth networks includes rapid growth of bursty datagram and other dynamic virtual-circuit services. Optical time-division multi-access (OTDM) networks can provide low-access-delay bandwidth on demand to support these services. Using optical techniques, future networks could operate at burst rates of 100 Gbit/s because OTDM techniques allow very high-speed optical logic and buffering that are capable of operating at these high data rates. Aspects of OTDM technology requirements are examined including HLAN architecture implementation.

O-E transmitter packaging for broadband access systems (FTTX)

Abstract: A 50 Mbits/sec burst-mode transceiver (TRx) has been demonstrated that uses a small, integrated optical module. The design of this TRx has potential in realizing a low cost module that will be suitable for the access telecom networks.

Impact of WDM network management on optical component functionalities

Abstract: WDM transport networks are moving fast from the laboratory and field trial environment to deployment in operational networks One of the key issues is the management of these transparent networks and the impact on the required component functionalities This paper will address these issues in more detail

Optical networking and the MONET project

Abstract: Summary form only given, as follows. In December 1994, a group of major US telecommunications industry players (AT & T, Bell Atlantic, Bellcore, BellSouth, Lucent Technologies, Pacific Telesis and Southwestern Bell) formed the Multiwavelength Optical Networking (MONET) Consortium, with partial support from the US Defense Advanced Research Projects Agency (DARPA), to investigate and advance the vision of national-scale optical networking. This vision is based on the creation of a configurable, reliable, high-capacity optical backbone network layer capable of supporting virtually all current and future telecommunications bit-rate, format and protocol standards across long-distance, local-exchange, and private networks. This talk summarizes the motivation and the status of the MONET project.

Network monitoring for passively split optical fibre networks

Abstract: Optical fibre networks offer an attractive solution to network operators for the distribution of video and other integrated broadband services to potential customers. One possible fibre network architecture for broadband distribution is the passive optical network (PON). It consists of a number of cascaded passive optical power splitters, originating from a single optical fibre, and it may be terminated at the customer's premises with optical nodes, wherein each node may contain a number of optical connectors and other optical components. The maintenance of such passively split networks presents a new set of challenges to service providers, as due to the star topology, the various branches of the network are likely be equidistant from the transmitter such that they cannot be sensibly probed and addressed from the head-end via a conventional maintenance instrument such as the optical time domain reflectometer. A frequency domain reflectometry technique is employed for characterising and monitoring the passively split optical fibre network, wherein, the reflectometer (OFDR) continuously interrogates the fibre network by reporting upon the status of reflective nodes distributed throughout the PON. (4 pages)

Fiber-to-the-home: 1997? 1998?

Abstract: On both telephone and cable fronts, attention has returned to "fiber-to-the-home" as a "now" solution. New networks and technologies have reduced costs, emphasis is shifting to "full-service" capabilities, and FTTH's costs and benefits are more-accurately understood.

Management in the WDM all-optical network

Abstract: The managed all-optical WDM transport network with the all- optical cross-connects is offering not only the high bandwidth, which can be shared between arbitrary clients accessing the network, by static allocation of the trails (also denoted as optical paths) or the virtual sub-networks, but also the service to perform reconfiguration of such virtual sub-networks and to reassign the capacity according to the demands and services required from the client, by the management actions. To fulfill the management task of providing the optical path, which is characterized by a set of optical parameters in the optical domain, the optical network management system must act upon the requirements of the different clients. This imposes that these requirements have their representation in the optical domain and vice versa. In this article we are investigating the possible approaches to WDM network management, first starting from the assumption that the capacity in the network can be arbitrarily shared between different transparent optical paths, and then introducing the analogous transmission parameters related to the transmission equipment and media which restrict this capability and make the management of the optical path dependent on the different types of the clients and different utilization of the capacity in the network. It is shown how those parameters are to be assigned to the different layers in the proposed layered architecture model of the optical network. This model is also discussed from the view point of the management integration and the optical QoS parameters mapping to the client QoS parameters are proposed.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An encryption scheme for high speed passive optical networks

Abstract: The prohibitive cost of dedicated fiber local loops for residential customers led to the development of passive optical networks (PONs) for access to broadband services. However the passive splitting of optical signals which gives flexibility, low cost and robustness creates a broadcast physical topology compromising customer privacy. Encryption is the only cost-effective way to prohibit global reception and create the required point-to point logical links restoring confidentiality to the desirable degree. Because of the very high speed of such networks, only solutions amenable to hardware implementations are acceptable. ATM cells are allocated to the system users on a time division basis each encrypted with a different key. A suitable for the PON environment encryption solution based on the summation generator stream cipher is presented with an outline of its hardware implementation.