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Named-Data Transport (NDT) is introduced to provide efficient content delivery by name over the existing IP Internet. NDT consists of the integration of three end-to-end architectural components: The first connection-free reliable transport protocol, the Named-Data Transport Protocol (NDTP); minor extensions to the Domain Name System (DNS) to include records containing manifests describing content; and transparent caches that track pending requests for content. NDT uses receiver-driven requests (Interests) to request content and NDT proxies that provide transparent caching of content while enforcing privacy. The performance of NDT, the Transmission Control Protocol (TCP), and Named-Data Networking (NDN) is compared using off-the-shelf implementations in the ns-3 simulator. The results demonstrate that NDT outperforms TCP and is as efficient as NDN, but without making any changes to the existing Internet routing infrastructure.
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Risk-Averse Caching Policies for YouTube Content in Femtocell Networks using Density Forecasting
The paper presents risk-neutral and risk-averse caching policies that can be deployed in a femtocell network with limited storage capacity to reduce the time delay of servicing content requests. The caching policies use a forecasting algorithm to estimate the cumulative distribution function of content requests based on the content features. Given the cumulative distribution function, a mixed-integer linear program is used to compute where to cache content in the femtocell network. The caching policies account for the uncertainty associated with estimating the content requests using the coherent Conditional Value-at-Risk (CVaR) measure. For a large number of content, a risk-neutral caching policy is constructed that accounts for both the content features and routing protocol that only requires the evaluation of a unimodular linear program. Using data from YouTube (comprising 25,000 videos) and the NS-3 simulator, the caching policies reduce the delay of retrieving content in femtocell networks compared with industry standard caching policies. Specifically, a 6\% reduction in delay is achieved by accounting for the uncertainty, and a 60\% reduction in delay is achieved if both the uncertainty and femtocell routing protocol are accounted for compared to the risk-neutral caching policy that neglects the routing protocol.
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- Award ID(s):
- 1714180
- PAR ID:
- 10091447
- Date Published:
- Journal Name:
- IEEE Transactions on Cloud Computing
- ISSN:
- 2372-0018
- Page Range / eLocation ID:
- 1 to 1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TCC.2018.2855160
