0 Using FPGA-Based Channel Bonding for HDTV Over DSL

On an almost daily basis, new video or voice applications push the bandwidth requirements for DSL networks, while telecom carriers in the U.S. and worldwide are targeting delivery of digital and high-definition television (HDTV) to consumers. To achieve delivery of such services without deploying new fiber everywhere, carriers must leverage existing copper deployments already in the ground.

Most DSL lines offer enough capacity for delivering standard-definition television (SDTV). Most programs are available from streaming servers at bitrates of about 750 kbps, with some programs providing a 1.5 Mbps bitrate. However, to allow high-quality HDTV streaming and multiple channels simultaneously, a home must have a bandwidth of at least 16 Mbps. Although newer DSL generations of ADSL2 and VDSL can offer these speeds, they cannot offer high speed over a sufficiently longer distance on a typical DSL line. Therefore, HDTV programs can be delivered only to households close to the DSLAM. Those located further away can only receive lower quality SDTV programming.

To ensure that DSL remains the preferred choice for end users, service providers are looking for new ways to improve the performance of DSL networks. While VDSL and ADSL2 provide better performance, the distance limitations are difficult to overcome. Another scenario is to bring the DSLAMs closer to the end users, but the costs involved with installing new equipment in the network are often prohibitive.

Channel Bonding in DSLAMs and DSL Modems
DSL channel bonding provides the ideal mix of features: higher bandwidth to all users and the ability to extend the distance that can be reached at a certain bandwidth. Instead of using a single copper pair, DSL bonding distributes traffic over a bundle of copper pairs. To achieve an effective bandwidth of 12 Mbps, three DSL lines of 4 Mbps are bundled, with a channel bonding processor at each end of the lines. In most copper networks, subscribers are already connected via several wires, so no new cables need be installed to provide channel bonding service, as shown in Figure 1.

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0 Using cartoons to Internet security lessons

Online fraud risks, organizations and individuals alike, and many fear that it can make into a weapon of electronic warfare in the not so distant future. There is a strong consensus that we need to improve our resilience against this threat as a society. This objective can be achieved with at least three main approaches: software-based security initiatives, legal and regulatory measures, and teaching methods. While the approaches complement each other, they are not completely independent. For example, the legal and administrative efforts due to technical problems regarding the recognition and enforcement are limited. Similarly, the effect of which educational efforts such as the technology advantage of client-side software initiatives, is and how you affected the integrity of the provided software. Guide [19] encouraged to educate their clients financial institutions in turn official fuel pump, software development and deployment efforts and the last FFEIC.

While technical efforts to combat the problem Proliferate and legal and regulatory approaches to quickly catch up, we argue that the development of the educational efforts were left behind. Consumers face a bewildering array of advice, how to stay safe against identity thieves, but we are not sure that the efforts to manage, communicate a fundamental understanding of what to do and why. Current advice comes in many forms, from the scarce online resources from financial institutions to detailed self-help books describe as reported, to get access to credit. Consumers should buy and use shredder; Find you for symbols indicating that sites are hacker safe, use encryption, and the members of the better Business Bureau. At the same time that typical Internet users do not know how to identify phishing e-Mail [48], but often [29] relies on the spell checking and identification of known deception techniques. Many consumers do not know how easy it is to interpret an existing site clone (such as using a tool like WebWhacker [57]), but convincing site layout as a sign of legitimacy. It is not surprising that the average consumer has a rudimentary understanding of the threat, both due to the fact that the intricacies of the Internet and complex because of the difficulties of communication concepts for users who would rather not at all involved in would be that he or she does not understand. To even worse, phishing, it is both a matter of technique and psychology [30, 49], and there is enough evidence (see, for example [39]), that most people trust what they want to see.

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