A Scalable Share Differentiation Architecture for Elastic and Real-Time Traffic

Today's Internet leacks the mechanisms necessary for traffic isolation (to divide resources fairly) and differentiation (to allocate resources to users according to their willingness to pay). In this work, we present a new architecture for relative service differentiation, Scalable Share Differentiation (SSD), which allocates network resources on a user basis and properly provides for both elastic and real-time traffic isolation and meaningful differentiation. SSD does not require the storage of any per-flow or per-user information at the core nodes and is inherently designed to work without admission control, making it easier to deploy and manage. In addition, we present how to provide more fine-grained flow control to users without changing the concepts of SSD, which permits users to choose different priorities for their packets/flows. This allows the integration of a novel concept for improving the service quality given to user flows: user-based admission control. With user-based admission control, the network is unaware of admission control decisions, and the user himself can perform the tasks of accepting, rejecting and prioritizing flows

SBSD: A Relative Differentiated Services Architecture based on Bandwidth Shares

With this work, we present a scalable relative differentiated services architecture based on bandwidth shares: Scalable Bandwidth Share Differentiation (SBSD). SBSD has been designed to provide isolation and differentiation of user traffic without per-flow or per-user state at the core nodes. In addition, SBSD preserves this isolation and differentiation when being scaled over domain boundaries. The presented SBSD architecture leads to a weighted maxmin fair bandwidth distribution with respect to each user's sending rate. The novelty of the resulting fairness distribution is that ist is user-based, in contrast to traditional fairness criteria dealing with flows. Even though SBSD operates at a per-user granularity, it allows more fine-grained differentiation, which we use to demonstrate how multicast can be integrated in a straight-forward manner and how SBSD can be optimized for end-to-end TCP congestion control

A Survey on TCP-Friendly Congestion Control (extended version)

New trends in communication, in particular the deployment of multicast and real-time audio/video streaming applications, are likely to increase the percentage of non-TCP traffic in the Internet. These applications rarely perform congestion control in a TCP-friendly manner, i.e., they do not share the available bandwidth fairly with applications built on TCP, such as web browsers, FTP- or email-clients. The Internet community strongly fears that the current evolution could lead to a congestion collapse and starvation of TCP traffic. For this reason, TCP-friendly protocols are being developed that behave fairly with respect to co-existent TCP flows. In this article, we present a survey of current approaches to TCP-friendliness and discuss their characteristics. Both unicast and multicast congestion control protocols are examined, and an evaluation of the different approaches is presented

Datacab: a geographical‐information‐system‐based expert system for the design of cable networks

Telecommunication networks have evolved over time as a result of technological advances, and network topologies and equipment have become increasingly complex. Expert systems are being successfully applied to the management of telecommunication networks. However, applying expert systems to network design is another especially beneficial yet still not very common approach. In this paper we propose a rule‐based expert system called Datacab. Datacab was developed at Enditel Endesa in collaboration with the Electronic Technology Department of the University of Seville, for the automatic design of hybrid fibre coax (HFC) cable networks. Using data from a geographical information system as input, it automatically generates viable HFC network designs

Spectral Analysis of Electricity Demand Using Hilbert–Huang Transform

The large amount of sensors in modern electrical networks poses a serious challenge in the data processing side. For many years, spectral analysis has been one of the most used approaches to extract physically meaningful information from a sea of data. Fourier Transform (FT) and Wavelet Transform (WT) are by far the most employed tools in this analysis. In this paper we explore the alternative use of Hilbert–Huang Transform (HHT) for electricity demand spectral representation. A sequence of hourly consumptions, spanning 40 months of electrical demand in Spain, has been used as dataset. First, by Empirical Mode Decomposition (EMD), the sequence has been time-represented as an ensemble of 13 Intrinsic Mode Functions (IMFs). Later on, by applying Hilbert Transform (HT) to every IMF, an HHT spectrum has been obtained. Results show smoother spectra with more defined shapes and an excellent frequency resolution. EMD also fosters a deeper analysis of abnormal electricity demand at different timescales. Additionally, EMD permits information compression, which becomes very significant for lossless sequence representation. A 35% reduction has been obtained for the electricity demand sequence. On the negative side, HHT demands more computer resources than conventional spectral analysis techniques

The subgroups of the phase III RECOURSE trial of trifluridine/tipiracil (TAS-102) versus placebo with best supportive care in patients with metastatic colorectal cancer

Background: In the phase III RECOURSE trial, trifluridine/tipiracil (TAS-102) extended overall survival (OS) and progression-free survival (PFS) with an acceptable toxicity profile in patients with metastatic colorectal cancer refractory or intolerant to standard therapies. The present analysis investigated the efficacy and safety of trifluridine/tipiracil in RECOURSE subgroups. Methods: Primary and key secondary end-points were evaluated using a Cox proportional hazards model in prespecified subgroups, including geographical subregion (United States of America [USA], European Union [EU], Japan), age (<65 years, ≥65 years) and v-Ki-ras2 Kirsten rat sarcoma 2 viral oncogene homologue (KRAS) status (wild type, mutant). Safety and tolerability were reported with descriptive statistics. Results: Eight-hundred patients were enrolled: USA, n = 99; EU, n = 403; Japan, n = 266. Patients aged ≥65 years and those with mutant KRAS tumours comprised 44% and 51% of all patients in the subregions, respectively. Final OS analysis (including 89% of events, compared with 72% in the initial analysis) confirmed the survival benefit associated with trifluridine/tipiracil, with a hazard ratio (HR) of 0.69 (95% confidence interval [CI] 0.59–0.81; P = 0.0001). Median OS in the three regions was 6.5–7.8 months in the trifluridine/tipiracil arm and 4.3–6.7 months in the placebo arm (USA: HR 0.56; 95% CI 0.34–0.94; P = 0.0277; EU: HR 0.62; 95% CI 0.48–0.80; P = 0.0002; Japan: HR 0.75; 95% CI 0.57–1.00; P = 0.0470). Median PFS was 2.0–2.8 months for trifluridine/tipiracil and 1.7–1.8 months for placebo; HRs favoured trifluridine/tipiracil in all regions. Similar clinical benefits of trifluridine/tipiracil were observed in elderly patients and in those with mutant KRAS tumours. There were no marked differences among subregions in terms of safety and tolerability. Conclusions: Trifluridine/tipiracil was effective in all subgroups, regardless of age, geographical origin or KRAS status

An aging Interventions Testing Program: study design and interim report

The National Institute on Aging's Interventions Testing Program (ITP) has developed a plan to evaluate agents that are considered plausible candidates for delaying rates of aging. Key features include: (i) use of genetically heterogeneous mice (a standardized four-way cross), (ii) replication at three test sites (the Jackson Laboratory, TJL; University of Michigan, UM; and University of Texas, UT), (iii) sufficient statistical power to detect 10 changes in lifespan, (iv) tests for age-dependent changes in T cell subsets and physical activity, and (v) an annual solicitation for collaborators who wish to suggest new interventions for evaluation. Mice in the first cohort were exposed to one of four agents: aspirin, nitroflurbiprofen (NFP), 4-OH- -phenyl-N-tert-butyl nitrone (4-OH-PBN), or nordihydroguiaretic acid (NDGA). An interim analysis was conducted using survival data available on the date at which at least 50 of the male control mice had died at each test site. Survival of control males was significantly higher, at the interim time-point, at UM than at UT or TJL; all three sites had similar survival of control females. Males in the NDGA group had significantly improved survival ( P 0.0004), with significant effects noted at TJL ( P < 0.01) and UT ( P < 0.04). None of the other agents altered survival, although there was a suggestion ( P 0.07) of a beneficial effect of aspirin in males. More data will be needed to determine if any of these compounds can extend maximal lifespan, but the current data show that NDGA reduces early life mortality risks in genetically heterogeneous mice at multiple test sites.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74625/1/j.1474-9726.2007.00311.x.pd