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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]

Extending an Internet subnet by connecting resource-constrained nodes (e.g., embedded sensors and actuators) over multiple wireless hops is necessary to support the future Internet of Things (IoT). RPL, the IPv6 routing standard for low-power and lossy networks, tried to achieve this goal but has not seen wide adoption in practice. As an alternative, Thread is a recently standardized low-power network protocol for IoT, driven by the Thread group, an industry consortium led by Google/Nest. We provide a comparative analysis of the technical aspects of RPL and Thread based on their specifications, explaining why using Thread, as opposed to RPL, may make sense for the future Internet. Specifically, the fundamental differences between RPL and Thread are their respective scopes and multihop network architectures, which result in Thread's unique design and advantages over RPL. Lastly, we evaluate Thread in an indoor multihop wireless testbed using OpenThread, an official open source implementation of Thread. This work serves as the first analysis of the Thread protocol in academia. [ABSTRACT FROM AUTHOR]

We describe a new vision of joint computation and communication resource management that goes beyond the end-to-end and client-server model of the current Internet. Enabled by a growing trend toward embedding processing and networking capabilities into "smart" network nodes and devices, for example, smartphones, watches, appliances, and automobiles, Dispersed Computing describes a new resource-centric architecture that leverages the diversity of networked computation points within the network, and the heterogeneity of network links and protocol stacks that connect them. We describe this new, resource-centric architecture as an evolution of both fog/edge networking and active networks. We illustrate the fundamental principles and the advantages over the current Internet architecture, and highlight several commercial use cases enabled by a dispersed computing architecture. [ABSTRACT FROM AUTHOR]

The Internet of Things has been widely deployed in various areas of daily life through heterogeneous communications protocols. Each unstandardized protocol focuses on a specific IoT communication pattern. Inspired by the Internet architecture over which divergent devices can easily be accessed and a considerable number of applications can be run, we propose a generic architecture for IoT. This architecture supports two DIY areas: network DIY for data aggregation and application DIY for service cooperation. To connect these two DIYs, a centralized controller has been designed to provide standardized interfaces for data acquisition, organization, and storage, and to support elastic and supportive computing. With these properties, divergent devices can coexist in a uniform microworld, and rich services can be developed and provided on demand to interoperate with physical devices. This article discusses the background, design principles, and advantages of the proposed architecture, as well as open problems and our initial solution, which substantiates a novel IoT architecture and new research ground. [ABSTRACT FROM PUBLISHER]

Network management is achieved through a large number of disparate solutions for different technologies and parts of the end-to-end network. Gaining an overall view, and especially predicting the impact on a service user, is difficult. Recently, a number of proprietary platforms have emerged to conduct end-to-end testing from user premises; however, these are limited in scale, interoperability, and the ability to compare like-for-like results. In this article we show that these platforms share similar architectures and can benefit from the standardization of key interfaces, test definitions, information model, and protocols. We take the SamKnows platform as a use case and propose an evolution from its current proprietary protocols to standardized protocols and tests. In particular, we propose to use extensions of the IETF?s IPFIX and NETCONF/YANG in the platform. Standardization will allow measurement capabilities to be included on many more network elements and user devices, providing a much more comprehensive view of user experience and enabling problems and performance bottlenecks to be identified and addressed. [ABSTRACT FROM PUBLISHER]

Troubleshooting network outages is a complex and time-consuming process. Network administrators are typically overwhelmed with large volumes of monitoring data, like SMTP and NetFlow measurements, from which it is very hard to separate between actionable and non-actionable events. In addition, they can only debug network problems using very basic tools, like ping and traceroute. In this context, intelligent correlation of measurements from different Internet locations is essential for analyzing the root cause of outages. However, correlating measurements across domains raises privacy concerns and hence is largely avoided. A possible solution to the privacy barrier is secure multi-party computation (MPC), that is, a set of cryptographic methods that enable a number of parties to aggregate private data without revealing sensitive information. In this article, we propose a distributed mechanism based on MPC for privacy-preserving correlation of NetFlow measurements from multiple ISPs, which helps in the diagnosis of network outages. We first outline an MPC protocol that can be used to analyze the scope (local, global, or semi-global) and severity of network outages across multiple ISPs. Then we use NetFlow data from a medium-sized ISP to evaluate the performance of our protocol. Our findings indicate that correlating data from several dozens of ISPs is feasible in near real time, with a delay of just a few seconds. This demonstrates the scalability and potential for real-world deployment of MPC-based schemes. Finally, as a case study we demonstrate how our scheme helped analyze, from multiple domains, the impact that Hurricane Sandy had on Internet connectivity in terms of scope and severity. [ABSTRACT FROM PUBLISHER]

This paper briefly describes Internet development in the Republic of Korea (South Korea), which started research and development on computer networking in the late 1970s. Korea became one of the first countries to deploy the Internet in 1982 [1], and organized one of the first global Internet conferences in 1985 [2]. In the late 1990s, Korea put much effort into development of broadband networks, starting from a master plan in 1995. Korea became a world leader with widely available wired and wireless broadband networks. Korea also led in Internet applications including online games, search engines and social networking services. As one of the earlier Internet countries, Korea has been vulnerable to newly arising problems on the Internet such as cybersecurity, net abuse and game addiction. Korea has been trying to solve these problems in collaboration with other leading countries. Korea has also shared its Internet experience with other countries, in particular with developing countries. A book is in preparation on the early history of the Internet in Korea [3] together with another, co-authored with Internet pioneers in other countries, on the early history of the Internet in Asia. [ABSTRACT FROM PUBLISHER]

In this article, we build a simple engineeringeconomic model to evaluate the incentives of various network players to deploy distributed storage nodes (content stores and caches) to support information-centric network (ICN) architectures and the implications of those incentives on protocol design, industry structure and other policy issues, such as competition and network- neutrality. We find that without some explicit monetary compensation from publishers, networks will fail to deploy the socially optimal number of caches. We also study the social welfare implications of different cache deployment scenarios and identify two deployment scenarios that maximize social welfare. Finally, we show that ICN architectures provide numerous opportunities for large eyeball networks to leverage their terminating access monopoly to extract more profits from other network players. Hence, regulators must take steps to address issues such as interconnection and the role of caching infrastructure in differential quality of service provisioning in an ICN-based network architecture, in order to ensure socially desirable outcomes from their deployment. [ABSTRACT FROM PUBLISHER]

Next-generation networks introduce an IPbased network foundation and more powerful access technologies. As a result, vulnerabilities in network protocol implementations can be exploited with Internet hacking tools to cause denial-of-service and distributed denial of service situations. Fuzzing is a black-box testing technique originally used by crackers to find exploitable vulnerabilities. In this article, we demonstrate how specification-based fuzzers can be used to discover exploitable vulnerabilities proactively to make networks and devices more robust against DoS and DDoS attacks. [ABSTRACT FROM PUBLISHER]

IPv6 is an essential building block of the evolution toward the future Internet. To take the full benefit of this protocol and exploit all its features, the future Internet needs to gracefully couple it with autonomics. In this article we demonstrate through our experience with network renumbering how the coupling of both IPv6 core functionality extended with major functions of the autonomic world can lead to fully autonomous activities of main management functions. We instantiate the notions of self-configuration, self-monitoring, self-protection, and self-healing in the network renumbering process and show how all together they can make renumbering a real success. We illustrate the various functions with the tools we have implemented to support them. [ABSTRACT FROM AUTHOR]

This article describes requirements and fundamental technologies to enable the provision of a new generation network beyond the Internet and the next generation network, both of which are based on IP protocols. Although the Internet has grown into a social infrastructure and the NGN will replace legacy telephone networks and cellular phone networks in the near future, it is time to start R&D on revolutionary network technologies and clean-slate designed architecture beyond the IP structure. Here some R&D activities for a new generation network are shown. This article is a revised version of the author's presentation in the First ITU-T Kaleidoscope Academic Conference [1] held in Geneva last May. [ABSTRACT FROM AUTHOR]

The convergence of wireless radio networks with all-IP networks has recently gained significant attention due to the ever increasing proliferation of IP technologies toward base stations as well as advances in air interfaces and wireless multimedia applications. Within standardization bodies, significant efforts are underway to address the support of QoS within the radio access network and Internet multimedia subsystem. For successful end-to-end application delivery, QoS and user profile unification are critical challenges, as is the intertwined policy enforcement between the IMS and the radio network. In this article we present a comprehensive analysis of QoS signaling over the integrated RAN and IMS domains. By using an imaginary service example, referred to as family media service, we analyze the specifics of end-to-end QoS invocation, control, and policy enforcement, including roaming scenarios. Based on laboratory measurements and simulations, we assess the call-setup delay, and recommend RAN and IMS signaling optimizations for delay reduction. We conclude the article by outlining open issues and proposing viable solutions. [ABSTRACT FROM AUTHOR]

This article presents an approach to delivering qualitative end-to-end quality of service (QoS) guarantees across the multiprovider Internet. We propose that bilateral agreements between a number of autonomous systems (ASs) result in the establishment of Q0S-class planes that potentially extend across the global Internet. The deployment of a QoS-enhanced Border Gateway Protocol (BGP) with different QoS- based route selection policies in each of the planes allows a range of interdomain QoS capabilities to coexist on the same network infrastructure. The article presents simulation results showing the benefits of the approach and discusses aspects of the performance of QoS-enhanced BGP. [ABSTRACT FROM AUTHOR]

The Internet is expected to support a variety of network services for its vast individual and business users. Advance reservation is a promising network service in which network resources are automatically allocated and reserved in advance of the time the resources are actually needed, which allows service providers to more efficiently manage network resources and thus provide better network services. For the next- generation Internet, the underlying transport infrastructure is evolving towards a network that integrates fiber-optic technology and Generalized Multi-Protocol Label Switching (GMPLS) technology. In this article we present a basic framework for automated provisioning of advance reservation service in the next-generation optical Internet, discuss the major issues involved, and explore possible solutions. It is also our hope to stimulate further studies in order to realize the vision of this promising net- work service. [ABSTRACT FROM AUTHOR]

In hybrid ad hoc networks, mobile nodes can communicate not only with each other in a self-organizing manner, but also with nodes on wired networks for extensive information retrieval and dissemination. In this article we consider efficient routing operations between any two nodes in an ad hoc network that is linked to wired networks by an access point. To build routes with low routing overhead efficiently, we develop a new routing scheme of region-based routing (RBR), which utilizes hop counts between mobile nodes and the access point to localize a route discovery within a limited topological region. Limiting the region of route discovery results in fewer routing messages and therefore reduces routing overhead. Simulation results show that the RBR scheme greatly reduces routing overhead while preserving a high rate of success for route discovery to the destination. [ABSTRACT FROM AUTHOR]

B3G wireless access infrastructures can be realized through the concept of cognitive networks. In a B3G context, a network operator will rely on various alternate wireless access technologies, for realizing the appropriate business goals, such as capacity and QoS levels. Cognitive wireless access networks dynamically change their configuration, and in this respect the radio access technologies and spectrum used at the physical and MAC layers, in order to adapt to environment conditions. A cognitive infrastructure consists of reconfigurable elements and intelligent management functionality. This article focuses on the management part. We present a platform, called m@ANGEL, which adheres to autonomic computing principles, and aims at the provision of seamless cognitive connectivity to the mobile Internet. Our work starts from a business level view of cognitive wireless access networks. Technical requirements for m@ANGEL are identified, and the architecture of the platform is described. Moreover, the article describes the functionality and engineering challenges of the m@ANGEL components, which provide the means for monitoring, discovery, context acquisition, description of profiles/goals/agreements, resource and service brokerage, configuration negotiation, selection, and implementation. Finally, concluding remarks are drawn, and issues for the next phases of our work are identified. [ABSTRACT FROM AUTHOR]

The Internet provides a platform for rapid and timely in formation exchange among a disparate array of clients and servers. TCP and IP are separately designed and closely tied protocols that define the rules of communication between end hosts, and are the most commonly used protocol suite for data transfer in the Internet. The combination of TCPIIP dominates today's communication in various networks from the wired backbone to the heterogeneous network due to its remarkable simplicity and reliability. TCP has become the de facto standard used in most applications ranging from interactive sessions such as Telnet and HTTP, to bulk data transfer like FTP. TCP was originally designed primarily for wired networks. In a wired network, random bit error rate, a characteristic usually more pronounced in the wireless network, is negligible, and congestion is the main cause of packet loss. The emerging wireless applications, especially high-speed multimedia services and the advent of wireless IP communications carried by the Internet, call for calibration and sophisticated enhancement or modifications of this protocol suite for improved performance. Based on the assumption that packet losses are signals of network congestion, the additive increase multiplicative decrease congestion control of the stan- dard TCP protocol reaches the steady state, which reflects the protocol's efficiency in terms of throughput and link utilization. However, this assumption does not hold when the end-to-end path also includes wireless links. Factors such as high BER, unstable channel characteristics, and user mobility may all contribute to packet losses. Many studies have shown that the unmodified standard TCP performs poorly in a wireless environment due to its inability to distinguish packet losses caused by network congestion from those attributed to transmission errors. In this article, following a brief introduction to TCP, we analyze the problems TCP exhibits in the wireless IP communication environment, and illustrate viable solutions by detailed examples. [ABSTRACT FROM AUTHOR]

Internetworking is a complex problem, traditionally tackled by splitting responsibilities between several layers of protocols arranged in a stack. A shortcoming of the current Internet suite's layers is that the responsibilities of individual layers are somewhat ill defined. The result is that frequently a feature may cause problems for higher layers when it unexpectedly exists lower in the stack, or may be unnecessarily and inefficiently implemented in multiple layers. Mobility is one such feature with no well defined place in classical protocol stacks. If a link layer hands over between two distinctly administered networks, a network layer protocol will likely need to acquire a new address. Similarly, if mobility is implemented at the network layer, such as with Mobile IP, transport layer protocols must be prepared to deal with a slew of problems (rapid changes in available capacity and delay, the asymmetry of triangle routes, and security policies, to name a few). Code for higher-level protocols (above transport) is less frequently reused, so higher-layer mobility schemes fail to leverage the large base of TCP sockets code. We discuss the various strengths and weaknesses of implementing mobility at three different layers of the protocol stack, concluding that a transport layer mobility scheme is likely to suit today's mobile Internet users best, and that ideally there should be more communication between layers to avoid conflict and inefficiency. [ABSTRACT FROM AUTHOR]

SONET/SDH technologies constitute the core transport infrastructure of major telecom service providers worldwide. As the percentage of packet-oriented traffic in the overall traffic demand continues to rise, prompted by the widespread adoption of the Internet Protocol suite, and recently by the fast adoption of Ethernet services, there is increasing pressure to improve the service provider's transport infrastructure in ways that make it data-aware and cost-effective for packet-oriented applications. Steps in this direction include the adoption of native physical interfaces, for Ethernet and storage area networks as service interfaces, or full integration of packet switching capabilites from Ethernet, Resilient Packet Ring, and MPLS technologies. This article discusses the emerging building blocks for next-generation data-aware transport networks and next-generation transport network elements. [ABSTRACT FROM AUTHOR]

Many new Internet applications require data transmission from a sender to multiple receivers. Unfortunately, the IP multicast technology used today suffers from scalability problems, especially when used for small and sparse groups. Multicast for small conferences (MSC) is a novel approach aimed at providing more efficient support for audio conferences, for example. It makes use of an IPv6 routing header. The unicast addresses of a small receiver group are put into the extension header in order to be forwarded to all group members. The results indicate that MSC has the potential to replace IP multicast for many delay-sensitive small group applications, even with very limited support from the network infrastructure. [ABSTRACT FROM AUTHOR]

Anycast is a new "one-to-one-of-many" communication method in IPv6 networks. With this technology, the problem of finding the best sewer to respond to a request becomes a virtual noop. Hindered by unresolved issues and the slow deployment of IPv6, network-layer anycast is still not a reality. However, an increase in interest and research surrounding anycast recently warrants a look at the state and direction of the ideas in this area. This article describes some of the major problems with network-layer anycast and their possible solutions, as well as some optimizations and applications that have been developed recently. [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]

The high demand for wireless Internet Connectivity has driven the development of highly efficient radio link technologies. However, their performance can be compromised by inadvertent interactions with the higher-layer TCP flow Control protocol. Maximizing the performance of wireless links requires that mechanisms operating at every layer of the protocol stack interact efficiently. This article provides a brief tutorial of some of these radio link enhancements. It then outlines how higher-layer flow control protocols should behave, and provides techniques for taming the behavior of TCP, to ensure that the performance of lower-layer enhancements is not compromised. [ABSTRACT FROM AUTHOR]

Due to volatile market conditions and increased competition, network operators and Internet service providers have been put under enormous pressure to cut costs while providing the same if not better levels of service to customers. Several aspects of network design are subject to review to assess possible cost savings while maintaining service levels and reliability. This article focuses on Internet Protocol network infrastructure design, and in particular investigates architectural options for interconnecting small "IP metro" PoPs to an "IP core" PoP. The baseline architecture is characterized by dual uplink circuits from the metro to the core PoP. Three variants of an alternative architecture based on a single uplink circuit from the metro to the core PoP are compared against the baseline network in terms of end-to-end availability/downtime and capital cost. [ABSTRACT FROM AUTHOR]

Describes the packet sequencing deterministic protocol for routing delay and loss-sensitive traffic through an Internet protocol (IP) network. Difference of the protocol from traditional approaches; Packet sequencing's use of a temporally-based deterministic protocol to coordinate and switch IP packets on a system-wide basis.

Presents a critical retrospective on the author's vision on Internet Protocol-optical integration. Control plane architectures; Data framing; Performance monitoring; Resource provisioning.

Proposes an approach to Interplanetary Internet. Need for network applications to communicate with counterparts across disparate networking environments characterized by different sets of physical and operational constraints; Overview of the Consultative Committee for Space Data Systems File Delivery Protocol; Implementation of the Internet routing system.

Proposes an extension on resource reservation protocol (RSVP) called dynamic RSVP (DRSVP) which can provided different reserved resources needed by different video resolutions to different receiver nodes. DRSVP model; DRSVP mechanisms; DRSVP example.

Focuses on the security risks of the accessibility of Internet Protocol-ready appliances from any remote computer connected to the Internet computer network. Responsibilities of network address translators; Proposal for a secure remote access framework; Example computer network configuration of remote access from office to home.

Focuses on the evolutionary trends on the role of Internet technology in future mobile data systems. Internet protocol services within mobile networks; Provision of wireless communications to mobile Internet users; Requirements of mobile Internet protocol.

Presents a study which discussed advances in wavelength-division multiplexing of optical networks. Impact of the growth of Internet traffic to Internet Protocol; Summary.

Describes a transmission control protocol (TCP) connection-admission-control-based strategy for bandwidth management of an Internet access link. Traffic engineering and load control for TCP-controlled flows; Monitoring and control architecture; Measurement results from a campus deployment; Conclusion.

Presents information on a study which described the routing protocols for ad hoc networks or wireless multihop networks. Forwarding architecture for active routing; Task of active routing packets for ad hoc networks; Review of cellular Internet Protocol (IP) which inspired the design of active cellular IP; Conclusions.

Presents a study which considered design issues of optical routers which combine the advantages of wavelength-division multiplexing with an optical switching technology. Use of optical Internet Protocol routers; What is fiber delay line; Results; Conclusions.

Presents a study which analyzed the Internet Protocol over asynchronous transfer mode (ATM) services from an ATM-centric standpoint. Overview of the increasing demand for Internet services; Conclusions.

Presents a study which provided a mechanism for Internet Protocol and asynchronous transfer mode (ATM) address resolution avoiding the use of Next Hop Resolution Protocol (NHRP). Issues in the interaction of NHRP and Resource Reservation Protocol (RSVP); Procedure for the support of ATM shortcuts; Definitions of the RSVP classes; Conclusions.

Presents a study which discussed the traffic engineering standards in Internet protocol networks using the multiprotocol label switching (MPLS). Handling of traffic in the Internet; Requirements for a signaling protocol; Conclusions.

Presents a study which discussed the role of multiprotocol label switching to the Internet architecture. Components of the Internet architecture; Evolution of the Internet routing architecture; Conclusion.

Presents a study which discussed the architectural aspects of multiprotocol label switching (MPLS) which enable it to address Internet Protocol traffic engineering management. Features of MPLS; Application of MPLS to traffic engineering.

Presents a study which discussed the role of multiprotocol label switching (MPLS) and traffic engineering in Internet Protocol (IP) networks. Instruments used by Internet service providers in meeting the challenge of Internet growth; Concepts of Internet traffic engineering; Components of the MPLS traffic engineering model; Conclusion.

Presents a study which examined distributed methods for fault recovery using modified Label Distribution Protocol (LDP) messages of multiprotocol label switching in the Internet. History of the Internet; Classes of LDP; Reliability of the Internet; Reasons for usefulness of computer network monitoring; 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.

Suggests the use of Internet protocols (IP) and technologies to enhance transport networks for efficient handling of data packets. Current time-division multiplexing (TDM)-based transport systems; Goals of packet transport systems; Architecture of packet transport networks.

Multicast communications for wireline users has been deployed in the Internet for atleast the past 10 years. In IP networks, a host joins a multicast group by informing a local multicast router, which in turn contacts other multicast routers; a multicast tree is thus created using any of the multicast routing protocols designed. Along with the widespread deployment of wireless networks, the fast-moving capabilities of mobile services and an increasingly sophisticated mobile workforce, content and service providers are increasingly interested in supporting multicast communications over wireless networks.

Discusses efforts to promote the IPv6 computer network protocol for the creation of quality and secure next-generation Internet in Europe. Highlights of the second Spanish Global IPv6 Summit held in Madrid, Spain on March 13-15, 2002; Plan of the European Commission to ask industry representatives to produce reports and recommendations to support and drive IPv6 transition.

Reports on the focus of the European Union/ACTS project demonstrations during the Telecommunication conference in 1999. Need to provide quality of service (QoS) to Internet protocol (IP) applications; Liberalization of the telecommunications market; Options for handling IP traffic with varying QoS requirements.

The move to Internet Protocol (IP)-based content delivery services has challenged the television industry by allowing high-quality television content to be delivered using the Internet, wired and wireless, private and public. The new convergence paradigm is already playing out its disruptive role as ?television? is now associated with both a personal and social experience using an ecosystem of devices. The unidirectional flow of content from an operator to a device has thus morphed into a much richer combination of real-time on-demand web and user generated content complementing traditional programming. [ABSTRACT FROM AUTHOR]

Peer-to-peer (P2P) content distribution systems are a major source of traffic in the Internet, but the application layer protocols they use are mostly unaware of the underlying network in accordance with the layered structure of the Internet's protocol stack. Nevertheless, the need for improved network efficiency and the business interests of Internet service providers (ISPs) are both strong drivers toward a cross-layer approach in peer-to-peer protocol design, calling for P2P systems that would in some way interact with the ISPs. Recent research shows that the interaction, which can rely on information provided by both parties, can be mutually beneficial. In this article we first give an overview of the kinds of information that could potentially be exchanged between the P2P systems and the ISPs, and discuss their usefulness and the ease of obtaining and exchanging them. We also present a classification of the possible approaches for interaction based on the level of involvement of the ISPs and the P2P systems, and we discuss the potential strengths and the weaknesses of these approaches. [ABSTRACT FROM PUBLISHER]

Low-cost wireless LAN equipment operating in unlicensed spectrum has revolutionized local area communications, introducing novel schemes for open wireless connectivity and even new business models. The ease of deployment of Wi-Fi has made it ubiquitous in densely populated urban areas, and it was just a matter of time before wireless communities emerged. Using inexpensive wireless technology to communicate, autonomous wireless internetworks have been built, offering a variety of broadband services. Based on our own experience participating in one of the largest wireless communities worldwide, the Athens Wireless Metropolitan Network, we attempt to explain their structure and mechanisms, study the reasons for their emergence and growth, and predict their future evolution. We expect that future wireless communities will be oriented toward providing broadband access to nomadic users. To this end, we have proposed that wireless network access be shared in a peer-to-peer, reciprocal manner. Thus, ubiquitous broadband Internet access can be achieved at a low cost, at least in metropolitan areas where there is abundant wireless coverage, providing an inexpensive alternative to broadband cellular services. [ABSTRACT FROM PUBLISHER]

Vehicular communication networks have emerged as a promising platform for the deployment of safety and infotainment applications. The stack of protocols for vehicular networks will potentially include Network Mobility Basic Support (NEMO BS) to enable IP mobility for infotainment and Internet-based applications. However, the protocol has performance limitations in highly dynamic scenarios, and several route optimization mechanisms have been proposed to overcome these limitations. This article addresses the problem of IP mobility and its specific requirements in vehicular scenarios. A qualitative comparison among the existent IP mobility solutions that optimize NEMO BS in vehicular networks is provided. Their improvements with respect to the current standard, their weaknesses, and their fulfillment of the specific requirements are also identified. In addition, the article describes some of the open research challenges related to IP mobility in vehicular scenarios. [ABSTRACT FROM PUBLISHER]