International Telecommunication Union-Telecommunication Standardization Sector Research Articles

HEVC: The New Gold Standard for Video Compression: How Does HEVC Compare with H.264/AVC?

Digital video has become ubiquitous in our everyday lives; everywhere we look, there are devices that can display, capture, and transmit video. The recent advances in technology have made it possible to capture and display video material with ultrahigh definition (UHD) resolution. Now is the time when the current Internet and broadcasting networks do not even have sufficient capacity to transmit large amounts of HD content-Let alone UHD. The need for an improved transmission system is more pronounced in the mobile sector because of the introduction of lightweight HD resolutions (such as 720 pixel) for mobile applications. The limitations of current technologies prompted the International Standards Organization/International Electrotechnical Commission Moving Picture Experts Group (MPEG) and International Telecommunication Union-Telecommunication Standardization Sector Video Coding Experts Group (VCEG) to establish the Joint Collaborative Team on Video Coding (JCT-VC), with the objective to develop a new high-performance video coding standard.

Optical Packet & Circuit Integrated Network for Future Networks

This paper presents recent progress made in the development of an optical packet and circuit integrated network. From the viewpoint of end users, this is a single network that provides both high-speed, inexpensive services and deterministic-delay, low-data-loss services according to the users' usage scenario. From the viewpoint of network service providers, this network provides large switching capacity with low energy requirements, high flexibility, and efficient resource utilization with a simple control mechanism. The network we describe here will contribute to diversification of services, enhanced functional flexibility, and efficient energy consumption, which are included in the twelve design goals of Future Networks announced by ITU-T (International Telecommunication Union - Telecommunication Standardization Sector). We examine the waveband-based network architecture of the optical packet and circuit integrated network. Use of multi-wavelength optical packet increases the switch throughput while minimizing energy consumption. A rank accounting method provides a solution to the problem of inter-domain signaling for end-to-end lightpath establishment. Moving boundary control for packet and circuit services makes for efficient resource utilization. We also describe related advanced technologies such as waveband switching, elastic lightpaths, automatic locator numbering assignment, and biologically-inspired control of optical integrated network.

The third ITU kaleidoscope conference: "innovations for digital inclusion"

This Standards section contains selected papers from the third International Telecommunication Union Telecommunication Standardization Sector (ITU-T) Kaleidoscope Academic Conference, organized with the technical co-sponsorship of the IEEE Communications Society. The aim of the Kaleidoscope conference series is to identify emerging developments in information and communication technologies (ICTs) at an early stage to generate successful products and services through the development of international and open standards.

LCOS-Based Wavelength Blocker Array With Channel-by-Channel Variable Center Wavelength and Bandwidth

We developed a new class of compact wavelength blocker (WB) array based on liquid crystal on silicon (LCOS), which enables per-channel control of not only the optical transmission power level but also channel center wavelength and channel bandwidth independently. We demonstrate an integrated device with WB array having 12 input/output ports for 50-GHz-spaced International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) channels over the entire C-band. The center wavelength and bandwidth can be adjusted independently with a minimum setting resolution of 3 and 6 GHz, respectively.

Extending next generation network (NGN) architecture for connection-oriented transport

Next Generation Network (NGN) is the architecture of the International Telecommunication Union-Telecommunication Standardization Sector (ITU-T in short) supporting the provisioning of Quality of Service (QoS)-guaranteed services over different packet transport technologies. Such capability derives from the effectiveness of a dynamic resource control performed by the Resource Admission Control Function (RACF) at service set-up. Control Plane (CP)-enabled connection-oriented transport networks can guarantee the QoS support for new bandwidth-greedy NGN services across the optical transport segment thanks to the ability of automatic path set-up and traffic segregation. But the Internet Engineering Task Force (IETF) standard for the CP in transport networks, i.e., the Generalized Multi-Protocol Label Switching (GMPLS) is not yet included within the NGN supported transport technologies. In this work, we outline architectural guidelines and design strategies for ITU-T RACF employment across GMPLS-controlled networks while providing a viable solution for dynamic resource control that takes into account operational issues for the integration of GMPLS capabilities within NGN architecture (i.e., supported interfaces, actual node capabilities). An NGN prototype implementing the proposed architectural enhancement is also presented as a proof of concept. The prototype highlights how the extended ITU-T NGN can set-up Multimedia over IP (MoIP) services using GMPLS-controlled transport objects.

The Second ITU-T Kaleidoscope Conference: "Innovations for Digital Inclusion" [Series Editorial

The seven articles in this Standards section are selected from the second International Telecommunication Union - Telecommunication Standardization Sector (ITU-T) Kaleidoscope Academic Conference, which took place in Mar del Plata, Argentina, 31 August-1 September 2009. The conference focus was on the role that standards play in "Innovations for Digital Inclusion."

Time and frequency distribution over packet switched networks

Moving from time division multiplexing (TDM)-based to packet-based network, frequency distribution has become a significant issue for network operators in view of strong requirements necessary for applications such as the backhauling of different wireless technologies. In this context the International Telecommunication Union, Telecommunication Standardization Sector (ITU-T), Internet Engineering Task Force (IETF) and Institute of Electrical and Electronics Engineers (IEEE) have competing standards to identify the right answer in terms of migration and achievable performance. This competition promotes segmentation of the network synchronization architecture, since the synchronization technologies are evolving separately at the expense of the benefits of interworking, potentially leading to future interoperability issues. Following a brief description of the aforementioned synchronization technologies focusing on their relative strengths and weaknesses, potential interworking schemes will be discussed. Both accurate frequency and time distribution will be considered. Time distribution, in particular, appears to be a key issue for emerging wireless network technologies, such as Worldwide Interoperability for Microwave Access (WiMAX) and Long Term Evolution (LTE). Finally, we will propose a new vision of a unified synchronization management approach in order to simplify the deployment of adapted synchronization technologies in various environments.

The first ITU-T kaleidoscope event: "Innovations in NGN" [Series Editorial

The five article's in this month's Feature Topic are updated versions of winning papers and invited papers presented at the first International Telecommunication Union - Telecommunication Standardization Sector (ITU-T) Kaleidoscope event that took place in Geneva, Switzerland on 12-13 May 2008.

Narrowband optical filters suitable for various applications in optical communications

We propose three types of narrowband optical filters based on a Fox-Smith resonator. We demonstrate that by choosing the appropriate combination of coating materials on each prism facet, one can design either a high reflectance or a high transmittance optical filter, suitable for low bit rate optical communication applications with International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) standards. We also show the possibility of designing an optical filter having a desirable finite reflectance/transmittance ratio with simultaneous peaks at ITU-T standard wavelengths. Such filters could be suitable for wavelength tuning applications.

Building secure products and solutions

Many security vulnerabilities in current information technology (IT) solutions and products are the result of a piecemeal “strap-on” security approach. The inclusion of many security add-ons, such as firewalls, antivirus software, intrusion detection systems (IDSs), and intrusion prevention systems (IPSs), may imply that the security objectives were an afterthought, not adequately defined initially, or that the required security objectives were never met by the individual system components. In fact, a “grounds-up” approach to security, where each component is individually secure, in a defined network deployment scenario helps meet the need of minimal risk exposure. Security should not be bolted on; rather, it should be the prime consideration from the beginning and throughout the entire lifecycle—from concept to deployment and ongoing operation for each product in the solution. Given the ever-increasing sophistication of attacks, developing and monitoring secure products have become increasingly difficult. Despite the wide- scale awareness of common security flaws in software products, e.g., buffer overflows, resource exhaustion, and structured query language (SQL) injection, the same flaws continue to exist in some of the current products. The objective of this paper is to introduce a technology-agnostic approach to integrating security into the product development lifecycle. The approach leverages the Bell Labs Security Framework, the foundation of the International Telecommunication Union, Telecommunication Standardization Sector (ITU-T) X.805 global standard. Building this framework into the product lifecycle supports the goal of realizing secure products. The security framework can be applied to any product domain to facilitate security requirements analysis and the development of usable tools such as checklists, guidelines, and security policies. The application of Bell Labs Security Framework concepts and its use in the development of secure products are illustrated using the example of a centrally managed firewall product. © 2007 Alcatel-Lucent.

ANIQUE+: A new American national standard for non-intrusive estimation of narrowband speech quality

Non-intrusive estimation of speech quality is a challenging problem in that the estimation has to be performed without the original reference speech signals. This paper presents a new American national standard (ANS) for non-intrusive estimation of narrowband speech quality. The proposed auditory non-intrusive quality estimation plus (ANIQUE+) model is a perceptual model simulating the functional roles of the human auditory system and employs improved modeling of quality estimation by a statistical learning paradigm. Experimental evaluation demonstrated that the performance of the ANIQUE+ model is significantly superior to that of the current International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) standard recommendation P.563 on 34 different subjective mean opinion score (MOS) databases. © 2007 Alcatel-Lucent.

Introduction to the Functional Architecture of NGN

In July 2006, International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) Study Group 13 initiated the approval process for a batch of framework Recommendations on the Next Generation Network (NGN) Release 1. One of the new Recommendations, Y.2012, illustrates the NGN from the viewpoint of a functional architecture consisting of various functional blocks, namely functional entities. In conjunction with this Recommendation, this paper explains how the NGN can be built and how the NGN utilizes functional entities to provide expected services and required capabilities. This paper also identifies open issues for extending the functional architecture towards Release 2.

Practical optical frequency measurement system around 1.5 μm based on an acetylene-stabilized laser-locked optical frequency comb

We have developed a practical and precise frequency measurement system at 1.5μm telecommunication band. An electro-optic-modulator based optical frequency comb is phase-locked to a dither-free acetylene-stabilized laser to realize an optical frequency comb with frequency uncertainty of 10kHz (5×10−11) and the linewidth of 15kHz. The present frequency comb can be also used as an optical frequency reference grid defined by ITU-T (International Telecommunication Union, Telecommunication Standardization Sector). Using the present frequency measurement system, we have demonstrated the first optical frequency measurement of 12C16O overtone absorption lines around 1.56μm with the uncertainty of lower than 900kHz.

Objective Assessment Methodology for Estimating Conversational Quality in VoIP

Voice over IP (VoIP) is becoming one of key technologies for telecommunications. Since IP networks generally do not guarantee transmission quality, it is extremely important to design and manage quality of service (QoS) properly. To do this, it is desirable to develop an objective quality assessment method that estimates subjective quality based on physical characteristics of VoIP system. This paper first proposes a framework of objective models that can be applied not only to quality planning, which is an intended application of existing standard methodology known as International Telecommunication Union - Telecommunication Standardization Sector (ITU-T) Recommendation G.107, the E-model, but also to quality benchmarking and management. Then, it proposes a model that complies with proposed framework. Experimental results show that proposed model has sufficient accuracy in evaluation of practical VoIP systems. In addition, we attempt to integrate opinion model with other objective quality measures, such as perceptual evaluation of speech quality (PESQ), standardized in Recommendation P.862 in ITU-T. Finally, we examine task dependence of performance of proposed model

FEC Performance Analysis Based on Poisson and Bursty Error Patterns for SDH and OTN Systems

This paper analyses and compares the performance of International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) recommended forward error correction (FEC) for the Synchronous digital hierarchy (SDH) system and the newly ratified Optical transport network (OTN) system. The analysis and comparison are based on simulation results using Poisson and bursty error patterns. While a Poisson error pattern is a commonly studied environment for these systems, a bursty error pattern is not. The simulation results show that the FEC for both SDH and OTN support Poisson errors well. However, for bursty errors, it is found that the FEC for SDH does not work well, while the FEC for OTN is working well for short burst length only.

IMS service-based bearer control

With the blurring of the lines between traditional telephony services and the growing number of Internet Protocol (IP)-based services available to customers of voice- and data-service providers, there is a growing need to provide a vertical interface between the service/session layer (where the service intelligence exists) and the transport layer (which provides the bearer path for service data traffic). The communication between the service/session layer and the bearer plane is referred to in standards organizations and in this paper as service-based bearer control (SBBC). The 3rd Generation Partnership Project (3GPP), the 3rd Generation Partnership Project 2 (3GPP2), the International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) Focus Group on Next Generation Networks, and other standards organizations are discussing interfaces to provide SBBC functionality. This paper addresses the requirements of the SBBC interfaces and provides information about the capabilities they provide, but it does not reflect any particular set of standards, because the standards in this area are still very much under development. Rather, it presents various issues that are being discussed and that will influence the standards that are ultimately agreed upon.

On managing optical services in future control-plane-enabled IP/WDM networks

This paper presents the design and experimental implementation of a service-oriented Internet Protocol (IP)/wavelength division multiplexing (WDM) management plane. In the proposed approach, compliant with International Telecommunication Union Telecommunication Standardization Sector (ITU-T)'s automatic-switched optical network (ASON), a distributed control plane performs signaling, routing, and discovery functions, and a decentralized management plane, both at information and architectural levels, performs cross-plane actions to enforce service establishment and monitoring with a view to guarantee service level agreements (SLAs). In-service monitoring provides status of optical resources and services by using spectral- and time-domain information. Some performance aspects of the approach are evaluated in a real testbed featuring dense wavelength multiplexing and a control plane based on the Internet Engineering Task Force (IETF)'s generalized multiprotocol label switching (GMPLS).

On the resource efficiency of virtual concatenation in SDH/SONET mesh transport networks bearing protected scheduled connections

Virtual concatenation (VCAT) is a Synchronous Digital Hierarchy (SDH)/Synchronous Optical Network (SONET) network functionality recently standardized by the International Telecommunication Union Telecommunication Standardization Sector (ITU-T). VCAT provides the flexibility required to efficiently allocate network resources to Ethernet, Fiber Channel (FC), Enterprise System Connection (ESCON), and other important data traffic signals. In this article, we assess the resources' gain provided by VCAT with respect to contiguous concatenation (CCAT) in SDH/SONET mesh transport networks bearing protected scheduled connection demands (SCDs). As explained later, an SCD is a connection demand for which the set-up and tear-down dates are known in advance. We define mathematical models to quantify the add/drop and transmission resources required to instantiate a set of protected SCDs in VCAT- and CCAT-capable networks. Quantification of transmission resources requires a routing and slot assignment (RSA) problem to be solved. We formulate the RSA problem in VCAT- and CCAT-capable networks as two different combinatorial optimization problems: RSA in VCAT-capable networks (RSAv) and RSA in CCAT-capable networks (RSAc), respectively. Protection of the SCDs is considered in the formulations using a shared backup path protection (SBPP) technique. We propose a simulated annealing (SA)-based meta-heuristic algorithm to compute approximate solutions to these problems (i.e., solutions whose cost approximates the cost of the optimal ones). The gain in transmission resources and the cost structure of add/drop resources making VCAT-capable networks more economical are analyzed for different traffic scenarios.

Creating an intelligent optical network worldwide interoperability demonstration

The Optical Internetworking Forum (OIF) conducted a world interoperability demonstration in conjunction with SUPERCOMM held in Chicago June 22-24, 2004. The demonstration was executed on a global stage with seven carriers across three continents internetworking through an intelligent control plane in a multivendor environment of 15 vendor participants. OIF's demonstration successfully included dynamic end-to-end connection management between client devices and transport network elements in a multidomain, multinode environment. The global connectivity included network elements (NEs) that incorporated the OIF optical user-to-network interface (UNI) and external network-to-network interfaces (E-NNI) among various vendors. Furthermore, carriers were able to test the new Ethernet over synchronous optical network/synchronous digital hierarchy (SONET/SDH) capabilities utilizing the generic framing procedure (GFP-F), virtual concatenation (VCAT), and the link capacity adjustment scheme (LCAS), based on International Telecommunication Union - Telecommunication Standardization Sector (ITU-T) recommendations. This article described the technical approach and execution of this demonstration.

Speech Playout Buffering Based on a Simplified Version of the ITU-T E-Model

In Internet-protocol (IP) telephony, problems of transmission delay variations are frequently addressed with adaptive dejitter buffering techniques. These are aimed at setting the buffer dimension so as to limit the packet end-to-end delay, the total packet loss, or both together. The selection of delay and loss limits is of key importance for the resulting conversational quality. This problem is addressed in this letter, whose main contribution is the introduction of a perceptually motivated optimality criterion that allows the receiver to automatically balance packet delay versus packet loss. In the proposed approach, the dejitter buffer size is adaptively set, and the adopted criterion relies on the use of a simplified version proposed by Cole and Rosenbluth of the conversational-quality International Telecommunication Union (ITU) Telecommunication Standardization Sector (ITU-T) E-Model.