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Protocol Version (protocol + version)

Distribution by Scientific Domains
Engineering50%

Selected Abstracts

An Evaluation of Qualitative Indexes of Physical Habitat Applied to Agricultural Streams in Ten U.S. States,

JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2010
Robert M. Hughes
Hughes, Robert M., Alan T. Herlihy, and Philip R. Kaufmann, 2010. An Evaluation of Qualitative Indexes of Physical Habitat Applied to Agricultural Streams in Ten U.S. States. Journal of the American Water Resources Association (JAWRA) 46(4): 792-806. DOI: 10.1111/j.1752-1688.2010.00455.x Abstract:, Assessment of stream physical habitat condition is important for evaluating stream quality globally. However, the diversity of metrics and methods for assessing physical habitat condition confounds comparisons among practitioners. We surveyed 51 previously sampled stream sites (0.0-6.3 m wide) located in regions of row-crop agriculture in Oregon, California, North Dakota, South Dakota, Nebraska, Iowa, Minnesota, Pennsylvania, Maryland, and West Virginia to evaluate the comparability of four indexes of physical habitat condition relative to each other. We also compared the indexes to previously calculated indexes of fish and macroinvertebrate condition. The physical habitat indexes included the Stream Visual Assessment Protocol Version 2 of the Natural Resources Conservation Service, the qualitative habitat evaluation index of the Ohio Environmental Protection Agency, the rapid bioassessment protocol of the United States Environmental Protection Agency (USEPA), and a qualitative physical habitat index based on USEPA quantitative physical habitat measurements. All four indexes were highly correlated with each other, but low-to-moderately correlated with biotic index scores for fish and macroinvertebrate assemblages. Moderately high correlations occurred between some macroinvertebrate biotic index scores and quantitative metrics. We conclude that additional research is needed to increase the predictive and diagnostic capabilities of qualitative physical habitat indexes. [source]

Formal specification of SNMPv3 entities using action semantics

INTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 5 2004
Elias P. Duarte Jr.
This work presents a formal description of the structure and behaviour of SNMPv3 entities. IETF documents describe the semantics of the Simple Network Management Protocol version 3 in an almost completely informal way. Our formal description is given using action semantics, a completely formal yet verbose framework for the specification of programming concepts. The purpose of our description is to specify management entities without ambiguities, contributing to a better understanding of the NMPv3 framework that may lead to automatic implementation and verification of agents and manager applications.,Copyright © 2004 John Wiley & Sons, Ltd. [source]

AAA architecture for mobile IPv6 based on WLAN

INTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 5 2004
R. C. Wang
Mobility support for Internet devices is quite important for consumer electronics. The number of the hand-held devices is growing quickly. However, there are not enough IP addresses for the number of the rapidly growing devices in the All-IP generation. Internet Protocol version 6 (IPv6) was therefore adopted to solve these problems. Our purposed structure is based on IEEE 802.11. However, IEEE 802.11 has a serious security drawback. Further, from the Internet Service Providers' point of view, accounting is a potential problem. A mechanism combining Mobile IPv6 and AAA based on IEEE 802.11 to overcome these problems is essential. Both Internet Protocol version 4 (IPv4) and IPv6 support IP security (IPsec) when data packets are exchanged across the IP network. IPsec operates at the IP layer. It can support system authentication and authorization, However, it lacks a system accounting function. Therefore ISPs cannot establish correct billing for their services. This is the reason why we chose to combine the wireless network and AAA functions. In this paper, the AAA mechanism is used to protect security, with the architecture having authentication, authorization, and accounting functions. We will discuss the benefits of AAA and state the reason why we choose to combine AAA with the mobility architecture.,Copyright © 2004 John Wiley & Sons, Ltd. [source]

IPv6 networks over DVB-RCS satellite systems

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 1 2008
Ricardo Castellot Lou
Abstract Satellite plays an important role in global information infrastructure (GII) and next generation networks (NGNs). Similarly, satellite communication systems have great advantages to support IPv6 (Internet Protocol version 6) networks as a technology that allows universal access to broadband e-services (audio, video, VPN, etc.). In the context of DVB-S2 (digital video broadcast-satellite) and DVB-RCS (digital video broadcast-return channel via satellite) standards, this paper presents the current SatSix project (satellite-based communications systems within IPv6 networks) within the European 6th Framework Programme, which is implementing innovative concepts and effective solutions (in relation with the economical cost) for broadband satellite systems and services using the technology presented above. This project is promoting the introduction of the IPv6 protocol into satellite-based communication systems. Moreover, through SatSix, the industry is addressing the next generation Internet, IPv6. It also enhances its competitive position in satellite broadband multimedia systems by exploiting the common components defined by the European DVB-S2 and DVB-RCS satellite broadband standards. Copyright © 2007 John Wiley & Sons, Ltd. [source]