The road to carrier-grade ethernet - [Topics in optical communications]

Carrier-grade Ethernet is the latest step in the three-decade development of Ethernet. This work describes the evolution of Ethernet technology from LAN toward a carrier-grade operation through an overview of recent enhancements. After reviewing native Ethernet and its transport shortcomings, we introduce the major carrier-grade upgrades. We first discuss the evolution of layer-2 architectures. Then, we detail the service specifications and their QoS and traffic engineering requirements. Finally, we describe the new OAM and resilience mechanisms.     

A dynamic impairment-aware networking solution for transparent mesh optical networks - [Topics in optical communications]

Core networks of the future will have a translucent and eventually transparent optical structure. Ultra-high-speed end-to-end connectivity with high quality of service and high reliability will be realized through the exploitation of optimized protocols and lightpath routing algorithms. These algorithms will complement a flexible control and management plane integrated in the proposed solution. Physical layer impairments and optical performance are monitored and incorporated in impairment-aware lightpath routing algorithms. These algorithms will be integrated into a novel dynamic network planning tool that will consider dynamic traffic characteristics, a reconfigurable optical layer, and varying physical impairment and component characteristics. The network planning tool along with extended control planes will make it possible to realize the vision of optical transparency. This article presents a novel framework that addresses dynamic cross-layer network planning and optimization while considering the development of a future transport network infrastructure.     

Sip-empowered optical networks for future it services and applications - [Topics in optical communications]

This article presents a novel applicationaware network architecture for evolving and emerging IT services and applications. It proposes to enrich an optical burst switching network with a session control layer that can close the gap between application requests and network control. The session control layer is implemented using the Session Initiation Protocol, giving birth to what is called a SIP-OBS architecture. The article discusses the important added value of this architecture, and shows that it may support a number of end-to-end resource discovery and reservation strategies (for both network and non-network resources). Finally, it presents a testbed implementation where this approach was experimentally validated.     

Toward efficient failure management for reliable transparent optical networks - [Topics in optical communications]

Security and reliability issues are of utmost importance in transparent optical networks due to the extremely large fiber throughput. Fast and successful reaction and restoration mechanisms performed by failure management can prevent loss of large amounts of critical data, which can cause severe service disruption. In this article we discuss failure management issues in TONs, the mechanisms involved, and optical monitoring techniques. Furthermore, we propose applying structural properties of self-organizing systems to create a "small world" hybrid supervisory plane that can enable faster system-wide communication. We also investigate the possibility of a scale-free structure aimed at improving robustness in the network and propose various topology generation algorithms.     

Photonic integration for high-volume, low-cost applications - [Topics in optical communications]

To date, photonic integration has seen only limited use in a few optical interface applications. The recently adopted IEEE draft standards for 40 Gb/s and 100 Gb/s Ethernet single-mode fiber local area network applications will change this situation. Although first generation implementations will use discrete components based on existing technologies, long-term requirements for significant reduction in cost, size, and power of 40 Gb/s and 100 Gb/s transceivers will lead to a broad demand for photonic integration. Both hybrid planar lightguide circuit and monolithic photonic integrated circuit are feasible approaches that meet the requirements of the new IEEE standards.     

Mupbed: a pan-european prototype for multidomain research networks - [Topics in optical communications]

Integration and full interoperability are challenging areas of research in wide area networks today. A European project, MUPBED, has recently concluded and achieved the main result of integrating and demonstrating technologies and network solutions that enable the operation of future European research infrastructures capable of supporting advanced applications. The achieved results are largely valid for any multidomain network scenario. The test network set up by the project is a prototype multidomain optical network able to provide connectivity on demand services across multiple domains directly driven by the applications. Rather than implementing ex novo a unified control plane and replacing existing equipment, the project approach has been to enable seamless interworking of different control planes by means of ASON/GMPLS and standardized network interfaces. This was done in accomplishment of the project target, which was to test and trial a common migration path toward the future European research network that should be followed by national research and education network operators, together with commercial operators. This article describes the main aspects of the MUPBED experience, which by its own peculiar nature provides deep insight into the most recent evolution of control-plane-enabled optical networking toward multidomain integration. Topics covered by the project and briefly related here include network architecture, applications, protocol and control software development, standardization issues, design, analysis and simulation, testing, measurement, and monitoring.     

On the state and guiding principles of broadband in india - [Topics in optical communications]

India, home to 1.2 billion people with a GDP growth of 9 percent, has been experiencing flat to modest growth of broadband services in the past decade despite the fact that the country continues to add 8?10 million cellular connections per month. In this article, we examine the reasons that affect the high cost of broadband in India and the steps required to reduce the cost. We also argue that the usage-based pricing model, which is used widely for billing retail customers, is hampering the growth of local content and services. In contrast, a flat-rate pricing model would spur demand for broadband services and enable content providers to target the local and emerging market. We study the Indian telecommunication scenario from a pricing and technology perspective to understand what the driving forces are for business to prosper. We then discuss the Indian landscape from a metro/access/core networks perspective. The technology choices and the methods of deployment are considered followed by an analysis of the service-centric model adopted by providers.     

Topics in integrated circuits for communications - [series editorial]

In this issue of Topics in Circuits for Communications Series, there are three articles that highlight circuit techniques and chip architectures for highly integrated wireless SoCs for high-data-rate systems using standard low-cost CMOS process.     

Public safety radios must pool spectrum - [Topics in radio communications]

The dynamic-spectrum-access research and development community is maturing technologies that will enable radios to share RF spectrum much more intensively. The adoption of DSA technologies by the public-safety community can better align systems with the future of wireless services, in general, and can contribute to making next-generation public-safety radio systems more robust, capable, and flexible. A critical first step toward a DSA-enabled future is to reform spectrum management to create spectrum pools that DSA-enabled devices, such as cognitive radios, can use iquest under the control of more dynamically flexible and adaptive prioritization policies than is possible with legacy technology. Appropriate reform will enable spectrum portability, facilitating the decoupling of spectrum rights from the provision of infrastructure. This article examines the economic, policy, and market challenges of enabling spectrum pooling and portability for public-safety radios.     

Challenges for GMPLS lightpath provisioning in transparent optical networks: wavelength constraints in routing and signaling - [Topics in optical communications]

GMPLS has introduced several enhancements to the MPLS-TE routing and signaling control plane protocols to handle dynamic lightpath provisioning in wavelength-routed networks. Specifically, the GMPLS signaling protocol has been enhanced to support two new provisioning functionalities, namely, the minimization of the setup delay, and the setup of bidirectional connection requests. In both cases, the source node must perform a wavelength allocation for either minimizing the setup delay (i.e., the suggested label) or requesting a bidirectional connection (i.e., the upstream label). However, these GMPLS provisioning functionalities present important deficiencies when applied to wavelength-routed networks with the wavelength continuity constraint, degrading the network performance considerably. The reason is that the standard GMPLS routing protocols flood link attributes only at bandwidth granularity, that is, no per-wavelength channel granularity is disseminated. Therefore, the source node is unable to perform an optimal wavelength assignment that fulfils the wavelength continuity constraint along the complete route toward the destination. In this article we present and experimentally evaluate an enhanced routing-based solution in the ADRENALINE testbed to handle the wavelength continuity constraint.     

Solving the routing and wavelength assignment problem in WDM networks for future planning - [Topics in optical communications]

In this article we define and analyze the routing and wavelength assignment problem by applying a virtual topology for both the optical network and the light paths. We introduce our developed algorithm to solve offline RWA problem. First the light path requests are constrained to repeated uniform distributed traffic. The reason is that this constraint permits us to study and analyze the behavior of the RWA problem. In addition, this constraint could be used as a benchmark to compare different algorithms. Then we relax the requests constraint to be non-uniform traffic. We show that the maximum number of assigned wavelengths depends on the number of traversed links, not on the shortest path length. Theorems are derived with proof to justify our algorithm. The effect of adding supplementary links to the WDM optical network is also explained to show how this approach could be used in the future planning for online operation. Finally, the result shows significant different in the number of wavelengths used compared to a recent backbone implemented network.     

Solitons-permanent waves [optical communications]

Communications engineers are learning to create an electromagnet wave at will, to transmit information. This wave, the optical soliton, is the subject of astounding recent developments in nonlinear optics and lasers. The author describes the principles behind the use of solitons in optical communications and shows that in the context of such communications the most important property of solitons is that they are extremely stable. Not only do they not disperse, but an encounter with a perturbation (e.g. a joint in optical fibre) will usually leave the soliton unaltered     

A technical framework for light- handed regulation of cognitive radios - [Topics in radio communications]

Light-handed regulation is discussed often in policy circles, but what it should mean technically has always been a bit vague. For cognitive radios to succeed in reducing the regulatory overhead, this has to change. For us, light-handed regulation means minimizing the mandates to be met at radio certification and relying instead on incentives to deter bad behavior. We put forth a specific technical framework in which the certification mandates are minimal - radios must modulate their transmitted waveform to embed an identity fingerprint, and radios must obey certain go-to-jail commands directed toward their identities. More specifically, the identity is represented by a temporal profile of taboo time slots in which transmission is impossible. The fraction of taboo slots represents the overhead of this approach and determines how reliably harmful interference can be attributed to the culprit(s) responsible. Meanwhile, the fraction of time that innocent radios spend in jail is the overhead for the punishment system. The analysis is carried out in the context of a real-time spectrum market, but is also applicable to opportunistic use.     

Topics in integrated circuits for communications [Series Editorial]

Over the past several years, mobile personal communication devices have converged to a few popular platforms including the smart phone, personal media player, and personal navigation device. More recently, a miniature laptop known as a netbook has also become increasingly widespread. Common in all these devices is the incorporation of multiple communication functions such as personal navigation, personal area networking, local area networking, wireless personal area networking, TV reception, and mobile cellular networking. Moreover, many of these functions are provided via different communications standards; for example, the Global Positioning System (GPS) for personal navigation, IEEE 802.11a/g/n (otherwise known as Wi-Fi) for wireless local area networking, and Bluetooth and IEEE 802.15.4 (ZigBee) for wireless personal area networking. In the case of TV broadcasting, standards are well established but extremely fragmented. A short list of digital TV broadcast standards includes DVB-H, DVB-T, ISDB-T, T-DMB, CMMB, and MediaFLO. Cellular standards likewise are still fragmented based on GSM/EDGE and WCDMA/UMTS although the cellular industry is working diligently toward a consolidated fourth-generation system based on Third Generation Partnership Project (3GPP) Long Term Evolution (LTE).     

Plastic optical fiber technology for reliable home networking: overview and results of the eu project pof-all - [Topics in optical communications]

The rising performance of broadband connections for residential users, particularly in conjunction with fiber to the home, will present a new challenge for telecom operators in the short and medium terms: how to deliver the high bit rate digital signals with high quality-of-service to all consumer devices scattered inside the building of final users? Among the many different solutions for the home network, we review in this article the use of polymer optical fibers for short-reach and high-capacity optical communications for residential customer premises. POF is an easy-to-install, low-cost, and eye-safe solution for these networks, with the potential of being future-proof. In this article the state of the art in POF technology is presented by summarizing significant results achieved in the European project POF-ALL. Data transmission rates of more than 1 Gb/s over 50+ m and 100 Mb/s over 200+ m of standard step-index POF have been shown.     

Next-generation PONs: a performance investigation of candidate architectures for next-generation access stage 1 - [Topics in optical communications]

Driven by bandwidth-demanding video applications, next-generation access stage 1, proposed by FSAN as the first stage of next-generation passive optical networks, increases the subscriber bandwidth by upgrading the current GPON network. To reduce the upgrading cost, NGA1 conforms to the standardized GPON and the deployed optical distribution network. This article presents the investigation of five candidate NGA1 architectures from the perspective of the MAC-layer bandwidth allocation including the analysis of the traffic characteristics of the subscribers? applications and the criteria in mapping them into proper transmission containers. Extensive simulations were conducted to investigate and compare the performances of the five candidate NGA1 architectures.