Title: Block-level packet recovery with network coding for wireless reliable multicast
Author(S) : Kaikai Chi,Xiaohong Jiang, Yi-hua Zhu, Jing Wang, Yanjun Li
Journal/Conference Name: Computer Networks
Volume: 57
Year: 2013
Issue: 4
Pages: 910-923
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Title: An Efficient Forward Error Correction Scheme for Wireless Sensor Network
Author(S) :M.P.Singha, Prabhat Kumarb
Journal/Conference Name: OpticalSwitchingandNetworking
:Volume
Year: 2012
:Issue
Pages: 737 – 742
Abstract
The two basic methods to recover erroneous packets in any network are Automatic Repeat Request (ARQ), and
Forward Error Correction (FEC). The life time of any wireless sensor network depends directly on the efficient use of
its power resources. Power is primarily consumed during wireless transmission and reception. As energy conservation
is a major issue of concern in WSN, repeat transmission is not an option and FEC would be preferred over ARQ. One
such FEC scheme is (16, 8) quasi cyclic code, which can be used to correct up to 2 Bit Errors and to detect 3 Bit
Errors. However, when more than 2 errors occur, retransmission of data is required. In this work, an efficient FEC
scheme for WSN’s has been developed to avoid retransmission which not only saves energy but also extends its
functionality and enables it to handle “BURST ERRORS”. The Proposed Error Correction Scheme is effective for
correcting Burst Errors of even 8 bits.
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PPR: Partial Packet Recovery for Wireless Networks
Kyle Jamieson and Hari Balakrishnan
MIT Computer Science and Artificial Intelligence Lab
{jamieson, hari}@csail.mit.edu
Abstract
Bit errors occur over wireless channels when the signal isn’t strong enough to
overcome the effects of interference and noise. Current wireless protocols may use
forward error correction (FEC) to correct for some (small) number of bit errors,
but generally retransmit the whole packet if the FEC is insufficient. We observe
that current wireless mesh network protocols retransmit a number of packets and
that most of these retransmissions end up sending bits that have already been received
multiple times, wasting network capacity. To overcome this inefficiency, we
develop, implement, and evaluate a partial packet recovery (PPR) system.
PPR incorporates three new ideas: (1) SoftPHY, an expanded physical layer
(PHY) interface to provide hints to the higher layers about how “close” the actual
received symbol was to the one decoded, (2) a postamble scheme to recover data
even when a packet’s preamble is corrupted and not decodable at the receiver,
and (3) PP-ARQ, an asynchronous link-layer retransmission protocol that allows a
receiver to compactly encode and request for retransmission only those portions of
a packet that are likely in error.
Our experimental results from a 27-node 802.15.4 testbed that includes Telos
motes with 2.4 GHz Chipcon radios and GNU Radio nodes implementing the
Zigbee standard (802.15.4) show that PPR increases the frame delivery rate by a
factor of 2× under moderate load, and 7× under heavy load when many links have
marginal quality.
LIEMRO_ A Low-Interference Energy-Efficient Multipath Routing Protocol for Improving QoS in Event-Based Wireless Sensor Networks
Marjan Radi, Behnam Dezfouli, Shukor Abd Razak, Kamalrulnizam Abu Bakar
Faculty of Computer Science and Information Systems
Universiti Teknologi Malaysia (UTM)
Johor, Malaysia
Abstract — In the recent years, multipath routing
techniques are recognized as an effective approach to
improve QoS in Wireless Sensor Networks (WSNs).
However, in most of the previously proposed protocols
either the effects of inter-path interference are ignored,
or establishing low-interference paths is very costly. In
this paper, we propose a Low-Interference Energyefficient
Multipath ROuting protocol (LIEMRO) for
WSNs. This protocol is mainly designed to improve
packet delivery ratio, lifetime, and latency, through
discovering multiple interference-minimized nodedisjoint
paths between source node and sink node. In
addition, LIEMRO includes a load balancing algorithm
to distribute source node’s traffic over multiple paths
based on the relative quality of each path. Simulation
results show that using LIEMRO in high traffic load
conditions can increase data reception rate and network
lifetime even more than 1.5x compared with single path
routing approach, while end-to-end latency reduces
significantly. Accordingly, LIEMRO is a multipath
solution for event-driven applications in which lifetime,
reliability, and latency are of great importance.
Keywords – Wireless Sensor Networks; QoS;
Multipath Routing; Load Balancing; Interference.
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