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Title Date Added Company

Performance Evaluation of Approximation Algorithms for Multipoint Relay Selection 0000-00-00 Macquarie University

In Mobile Ad hoc NETworks (MANET), the selection of Multipoint Relays provides an efficient routing scheme for efficient broadcast and shortest-path unicast. As such a selection is NP-hard, a heuristic has been designed and effectively implemented in protocols for MANET such as the Optimized Link State Routing protocol (OLSR). This paper introduces other heuristics that consider the impact of collision by exploiting the topological properties of the network (without assuming knowledge of geographic positions or geometric properties). For each heuristic, the paper gives its respective provable guaranteed approximation performance when compared to a solution of optimal value.

Tags: Software Engineering, Mobile - Wireless Communications

Modeling the Performance of Flooding in Wireless Multi-Hop Ad Hoc Networks 0000-00-00 University of California

One feature common to most existing routing protocols for wireless mobile ad hoc networks, or MANETs, is the need to flood control messages network-wide during the route acquisition and maintenance process. Flooding of control messages may result in redundant broadcasts and cause serious contention and collision problems in MANETs. This paper develops an analytical model to study the performance of plain- and probabilistic flooding in terms of its reliability and reachability in delivering packets. Reliability is a measure of the total number of packets received by network nodes whereas reachability refers to the total number of unique nodes reached by the flooding process.

Tags: Wireless

Partial Topology in an MPR-Based Solution for Wireless OSPF on Mobile Ad Hoc Networks 2007-03-15 French National Institute for Research in Computer Science and Control

Using reduced topology within link state routing has proven to be an efficient way to decrease routing overhead while still providing sufficient route quality. There are various ways to achieve topology reduction, based on different ways to form a backbone in the network - this backbone usually originates from the flooding optimization scheme in use, such as MPR or CDS. In case of mobile ad hoc networks, flooding using MPR backbones is preferable as it is more robust in face of topology changes, compared to flooding using CDS backbones. This text therefore describes several methods to enable the use of reduced topology in wireless OSPF for MANETs, when MPR-based flooding optimizations are used.

Tags: Mobile - Wireless Communications

Toward Broadcast Reliability in Mobile Ad Hoc Networks With Double Coverage 2007-02-01 Institute of Electrical and Electronics Engineers

The broadcast operation, as a fundamental service in Mobile Ad hoc NETworks (MANETs), is prone to the broadcast storm problem if forwarding nodes are not carefully designated. The objective of reducing broadcast redundancy while still providing high delivery ratio under high transmission error rate is a major challenge in MANETs. This paper proposes a simple broadcast algorithm, called Double-Covered Broadcast (DCB), which takes advantage of broadcast redundancy to improve the delivery ratio in an environment that has rather high transmission error rate. Among the 1-hop neighbors of the sender, only selected forwarding nodes retransmit the broadcast message.

Tags: Mobile - Wireless Communications

Towards an Information Theory of Large Networks: An Achievable Rate Region 2006-12-13 01:00:24 Alcatel-Lucent

This paper studies communication networks of arbitrary size and topology and communicating over a general vector discrete memoryless channel. The paper proposes an information-theoretic constructive scheme for obtaining an achievable rate region in such networks. Many well-known capacity-defining achievable rate regions can be derived as special cases of the proposed scheme. A few such examples are the physically degraded and reversely-degraded relay channels, the Gaussian multiple-access channel, and the Gaussian broadcast channel. The proposed scheme also leads to inner bounds for the multicast and allcast capacities.

How Does Ping Really Work? 2006-10-01 Global Knowledge

Ping is an Internet program that most of us use daily, but do you know how it really works? Gain an understanding of the cycle of processing associated with ping.

Limited Flooding Protocol for Mobile Ad Hoc Networks 2006-09-08 University of Guelph

Mobile ad hoc networks are collections of mobile nodes without any fixed infrastructure or central co-ordinating mechanism for packet routing. Consequently, routing is a challenge. This paper proposes a multipath routing protocol called Limited Flooding. The protocol is fully reactive and does not entail the computation of routing tables. It uses the basic features of flooding but restricts packet propagation by selecting a limited number of links. Discrete-event simulation is used to model ad hoc networks, and the performance of several variations of the protocol is evaluated.

Tags:

Rainbow Media Selects Scientific Atlanta Systems for Analog-to-Digital Content Distribution Migration 2006-05-03 Cisco Systems

Rainbow Media Holdings LLC has selected multiple Scientific Atlanta PowerVu digital content distribution systems for the analog-to-digital migration of North American programming delivery to its affiliates. Scientific Atlanta will provide two PowerVu multiplexes for the delivery of Standard Definition (SD) and High-Definition (HD) programming from uplink facilities in Bethpage, NY. In addition, Rainbow Media has purchased a backup PowerVu SD multiplex system for deployment in Belmont, N.Y., and will rely on Scientific Atlanta for assistance in distributing more than 6,000 PowerVu Integrated Receiver/Decoders (IRDs) to its cable affiliates.

Tags: Network Design

Information Dissemination Via Wireless Broadcast 2006-03-20 Hong Kong University of Science and Technology

The advent of sensor, wireless and portable device technologies will soon enable one to embed computing technologies transparently in the environment to provide uninterrupted services for one's daily life. With temperature and location sensors and wireless access points embedded in an environment, a person entering an environment can be automatically connected to the environment. All of his personal computing devices will then be adapted to the context, making all important information readily available for the user to tackle his tasks at hand. An important step towards the realization of this pervasive environment is to be able to disseminate timely and relevant information to the user anytime, anywhere.

Tags: Knowledge and Data Management,

Capacity Theorems for Cooperative Relay Broadcast Channels 2006-12-13 01:00:24 Alcatel-Lucent

The partially cooperative Relay Broadcast Channel (RBC) is studied in this paper, where a source transmits to two users, and one user also acts as a relay node to assist broadcast communication. The source has common information intended for both users and private information for each user. Inner and outer bounds on the capacity region are derived for discrete memoryless partially cooperative RBCs. These bounds are further refined for three example channels: partially cooperative RBCs with degraded message sets, semideterministic partially cooperative RBCs, and orthogonal partially cooperative RBCs. The inner and outer bounds are shown to match for the latter two channels, and hence the capacity regions are established.

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Title	Date Added	Company
Performance Evaluation of Approximation Algorithms for Multipoint Relay Selection	0000-00-00	Macquarie University
In Mobile Ad hoc NETworks (MANET), the selection of Multipoint Relays provides an efficient routing scheme for efficient broadcast and shortest-path unicast. As such a selection is NP-hard, a heuristic has been designed and effectively implemented in protocols for MANET such as the Optimized Link State Routing protocol (OLSR). This paper introduces other heuristics that consider the impact of collision by exploiting the topological properties of the network (without assuming knowledge of geographic positions or geometric properties). For each heuristic, the paper gives its respective provable guaranteed approximation performance when compared to a solution of optimal value. Tags: Software Engineering, Mobile - Wireless Communications
Modeling the Performance of Flooding in Wireless Multi-Hop Ad Hoc Networks	0000-00-00	University of California
One feature common to most existing routing protocols for wireless mobile ad hoc networks, or MANETs, is the need to flood control messages network-wide during the route acquisition and maintenance process. Flooding of control messages may result in redundant broadcasts and cause serious contention and collision problems in MANETs. This paper develops an analytical model to study the performance of plain- and probabilistic flooding in terms of its reliability and reachability in delivering packets. Reliability is a measure of the total number of packets received by network nodes whereas reachability refers to the total number of unique nodes reached by the flooding process. Tags: Wireless
Partial Topology in an MPR-Based Solution for Wireless OSPF on Mobile Ad Hoc Networks	2007-03-15	French National Institute for Research in Computer Science and Control
Using reduced topology within link state routing has proven to be an efficient way to decrease routing overhead while still providing sufficient route quality. There are various ways to achieve topology reduction, based on different ways to form a backbone in the network - this backbone usually originates from the flooding optimization scheme in use, such as MPR or CDS. In case of mobile ad hoc networks, flooding using MPR backbones is preferable as it is more robust in face of topology changes, compared to flooding using CDS backbones. This text therefore describes several methods to enable the use of reduced topology in wireless OSPF for MANETs, when MPR-based flooding optimizations are used. Tags: Mobile - Wireless Communications
Toward Broadcast Reliability in Mobile Ad Hoc Networks With Double Coverage	2007-02-01	Institute of Electrical and Electronics Engineers
The broadcast operation, as a fundamental service in Mobile Ad hoc NETworks (MANETs), is prone to the broadcast storm problem if forwarding nodes are not carefully designated. The objective of reducing broadcast redundancy while still providing high delivery ratio under high transmission error rate is a major challenge in MANETs. This paper proposes a simple broadcast algorithm, called Double-Covered Broadcast (DCB), which takes advantage of broadcast redundancy to improve the delivery ratio in an environment that has rather high transmission error rate. Among the 1-hop neighbors of the sender, only selected forwarding nodes retransmit the broadcast message. Tags: Mobile - Wireless Communications
Towards an Information Theory of Large Networks: An Achievable Rate Region	2006-12-13 01:00:24	Alcatel-Lucent
This paper studies communication networks of arbitrary size and topology and communicating over a general vector discrete memoryless channel. The paper proposes an information-theoretic constructive scheme for obtaining an achievable rate region in such networks. Many well-known capacity-defining achievable rate regions can be derived as special cases of the proposed scheme. A few such examples are the physically degraded and reversely-degraded relay channels, the Gaussian multiple-access channel, and the Gaussian broadcast channel. The proposed scheme also leads to inner bounds for the multicast and allcast capacities.
How Does Ping Really Work?	2006-10-01	Global Knowledge
Ping is an Internet program that most of us use daily, but do you know how it really works? Gain an understanding of the cycle of processing associated with ping.
Limited Flooding Protocol for Mobile Ad Hoc Networks	2006-09-08	University of Guelph
Mobile ad hoc networks are collections of mobile nodes without any fixed infrastructure or central co-ordinating mechanism for packet routing. Consequently, routing is a challenge. This paper proposes a multipath routing protocol called Limited Flooding. The protocol is fully reactive and does not entail the computation of routing tables. It uses the basic features of flooding but restricts packet propagation by selecting a limited number of links. Discrete-event simulation is used to model ad hoc networks, and the performance of several variations of the protocol is evaluated. Tags:
Rainbow Media Selects Scientific Atlanta Systems for Analog-to-Digital Content Distribution Migration	2006-05-03	Cisco Systems
Rainbow Media Holdings LLC has selected multiple Scientific Atlanta PowerVu digital content distribution systems for the analog-to-digital migration of North American programming delivery to its affiliates. Scientific Atlanta will provide two PowerVu multiplexes for the delivery of Standard Definition (SD) and High-Definition (HD) programming from uplink facilities in Bethpage, NY. In addition, Rainbow Media has purchased a backup PowerVu SD multiplex system for deployment in Belmont, N.Y., and will rely on Scientific Atlanta for assistance in distributing more than 6,000 PowerVu Integrated Receiver/Decoders (IRDs) to its cable affiliates. Tags: Network Design
Information Dissemination Via Wireless Broadcast	2006-03-20	Hong Kong University of Science and Technology
The advent of sensor, wireless and portable device technologies will soon enable one to embed computing technologies transparently in the environment to provide uninterrupted services for one's daily life. With temperature and location sensors and wireless access points embedded in an environment, a person entering an environment can be automatically connected to the environment. All of his personal computing devices will then be adapted to the context, making all important information readily available for the user to tackle his tasks at hand. An important step towards the realization of this pervasive environment is to be able to disseminate timely and relevant information to the user anytime, anywhere. Tags: Knowledge and Data Management,
Capacity Theorems for Cooperative Relay Broadcast Channels	2006-12-13 01:00:24	Alcatel-Lucent
The partially cooperative Relay Broadcast Channel (RBC) is studied in this paper, where a source transmits to two users, and one user also acts as a relay node to assist broadcast communication. The source has common information intended for both users and private information for each user. Inner and outer bounds on the capacity region are derived for discrete memoryless partially cooperative RBCs. These bounds are further refined for three example channels: partially cooperative RBCs with degraded message sets, semideterministic partially cooperative RBCs, and orthogonal partially cooperative RBCs. The inner and outer bounds are shown to match for the latter two channels, and hence the capacity regions are established.