2,974 research outputs found
From Instantly Decodable to Random Linear Network Coding
Our primary goal in this paper is to traverse the performance gap between two
linear network coding schemes: random linear network coding (RLNC) and
instantly decodable network coding (IDNC) in terms of throughput and decoding
delay. We first redefine the concept of packet generation and use it to
partition a block of partially-received data packets in a novel way, based on
the coding sets in an IDNC solution. By varying the generation size, we obtain
a general coding framework which consists of a series of coding schemes, with
RLNC and IDNC identified as two extreme cases. We then prove that the
throughput and decoding delay performance of all coding schemes in this coding
framework are bounded between the performance of RLNC and IDNC and hence
throughput-delay tradeoff becomes possible. We also propose implementations of
this coding framework to further improve its throughput and decoding delay
performance, to manage feedback frequency and coding complexity, or to achieve
in-block performance adaption. Extensive simulations are then provided to
verify the performance of the proposed coding schemes and their
implementations.Comment: 30 pages with double space, 14 color figure
Wireless Broadcast with Network Coding in Mobile Ad-Hoc Networks: DRAGONCAST
Network coding is a recently proposed method for transmitting data, which has
been shown to have potential to improve wireless network performance. We study
network coding for one specific case of multicast, broadcasting, from one
source to all nodes of the network. We use network coding as a loss tolerant,
energy-efficient, method for broadcast. Our emphasis is on mobile networks. Our
contribution is the proposal of DRAGONCAST, a protocol to perform network
coding in such a dynamically evolving environment. It is based on three
building blocks: a method to permit real-time decoding of network coding, a
method to adjust the network coding transmission rates, and a method for
ensuring the termination of the broadcast. The performance and behavior of the
method are explored experimentally by simulations; they illustrate the
excellent performance of the protocol
Centralized and Cooperative Transmission of Secure Multiple Unicasts using Network Coding
We introduce a method for securely delivering a set of messages to a group of
clients over a broadcast erasure channel where each client is interested in a
distinct message. Each client is able to obtain its own message but not the
others'. In the proposed method the messages are combined together using a
special variant of random linear network coding. Each client is provided with a
private set of decoding coefficients to decode its own message. Our method
provides security for the transmission sessions against computational
brute-force attacks and also weakly security in information theoretic sense. As
the broadcast channel is assumed to be erroneous, the missing coded packets
should be recovered in some way. We consider two different scenarios. In the
first scenario the missing packets are retransmitted by the base station
(centralized). In the second scenario the clients cooperate with each other by
exchanging packets (decentralized). In both scenarios, network coding
techniques are exploited to increase the total throughput. For the case of
centralized retransmissions we provide an analytical approximation for the
throughput performance of instantly decodable network coded (IDNC)
retransmissions as well as numerical experiments. For the decentralized
scenario, we propose a new IDNC based retransmission method where its
performance is evaluated via simulations and analytical approximation.
Application of this method is not limited to our special problem and can be
generalized to a new class of problems introduced in this paper as the
cooperative index coding problem
On Throughput and Decoding Delay Performance of Instantly Decodable Network Coding
In this paper, a comprehensive study of packet-based instantly decodable
network coding (IDNC) for single-hop wireless broadcast is presented. The
optimal IDNC solution in terms of throughput is proposed and its packet
decoding delay performance is investigated. Lower and upper bounds on the
achievable throughput and decoding delay performance of IDNC are derived and
assessed through extensive simulations. Furthermore, the impact of receivers'
feedback frequency on the performance of IDNC is studied and optimal IDNC
solutions are proposed for scenarios where receivers' feedback is only
available after and IDNC round, composed of several coded transmissions.
However, since finding these IDNC optimal solutions is computational complex,
we further propose simple yet efficient heuristic IDNC algorithms. The impact
of system settings and parameters such as channel erasure probability, feedback
frequency, and the number of receivers is also investigated and simple
guidelines for practical implementations of IDNC are proposed.Comment: This is a 14-page paper submitted to IEEE/ACM Transaction on
Networking. arXiv admin note: text overlap with arXiv:1208.238
Multi-user video streaming using unequal error protection network coding in wireless networks
In this paper, we investigate a multi-user video streaming system applying unequal error protection (UEP) network coding (NC) for simultaneous real-time exchange of scalable video streams among multiple users. We focus on a simple wireless scenario where users exchange encoded data packets over a common central network node (e.g., a base station or an access point) that aims to capture the fundamental system behaviour. Our goal is to present analytical tools that provide both the decoding probability analysis and the expected delay guarantees for different importance layers of scalable video streams. Using the proposed tools, we offer a simple framework for design and analysis of UEP NC based multi-user video streaming systems and provide examples of system design for video conferencing scenario in broadband wireless cellular networks
Random Linear Network Coding for 5G Mobile Video Delivery
An exponential increase in mobile video delivery will continue with the
demand for higher resolution, multi-view and large-scale multicast video
services. Novel fifth generation (5G) 3GPP New Radio (NR) standard will bring a
number of new opportunities for optimizing video delivery across both 5G core
and radio access networks. One of the promising approaches for video quality
adaptation, throughput enhancement and erasure protection is the use of
packet-level random linear network coding (RLNC). In this review paper, we
discuss the integration of RLNC into the 5G NR standard, building upon the
ideas and opportunities identified in 4G LTE. We explicitly identify and
discuss in detail novel 5G NR features that provide support for RLNC-based
video delivery in 5G, thus pointing out to the promising avenues for future
research.Comment: Invited paper for Special Issue "Network and Rateless Coding for
Video Streaming" - MDPI Informatio
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