Minimizing Transmission Cost for Third-Party Information
Exchange with Network Coding
ABSTRACT:
In wireless networks, getting the global knowledge
of channel state information (CSI, e.g., channel gain or link loss probability)
is always beneficial for the nodes to optimize the network design. However, the
node usually only has the local CSI between itself and other nodes, and lacks
the CSI between any pair of other nodes. To enable all the nodes to get the
global CSI, in this paper, we propose a network-coded third-party information
exchange scheme, with an emphasis on minimizing the total transmission cost for
exchanging the CSI among the nodes. We show that for a network of N nodes, if
and only if any k nodes (1 _ k < N) send at least k2 packets, a feasible
solution exists for third-party information exchange. Formulating the problem
of feasible and optimal solutions as an integer linear programming (ILP)
problem, we compute the optimal number of packets that must be transmitted by
every node. Guided by the necessary and sufficient condition, we construct two
practical transmission schemes: fair load (FL) scheme and proportional load
(PL) scheme. A deterministic encoding strategy based on XORs coding over GF(2)
is further designed to guarantee that with FL or PL scheme, each node finally
can decode the complete packets. It is shown that in two specific networks,
these two schemes are optimal, achieving the minimum transmission cost. In more
general networks, simulation results show that PL is still close to optimal with
a high probability. Finally, a distributed transmission protocol is developed,
which allows FL and PL schemes to be operated in a distributed and hence
scalable manner.
EXISTING SYSTEM:
v Network
coding, a cross-layer technology that was initially developed for static
(wireline) networks has received extensive research attention in wireless
community, due to its significant benefits in improving wireless performance
including throughput, reliability and etc.
v Recent
studies show that network coding can also help reduce the number of
transmissions or the transmission delay/cost for general cooperative data
exchange.
v An
earlier study of third-party information exchange demonstrated the existence of
optimal solutions, where the optimality is measured in terms of minimizing the
total number of transmissions.
v The
existing researches on cooperative data exchange mainly focus on minimizing the
total number of packets required to exchange, the total transmission cost/delay
or fixing the security issues.
DISADVANTAGES
OF EXISTING SYSTEM:
§ The
problem of third-party information exchange presents a special case of the
general problem of cooperative data exchange.
§ However,
finding the deterministic code design to achieve these limits for cooperative
data exchange can be non-trivial as it needs very high field size, and the
complication comes, in part, from the very general setup of cooperative data
exchange.
PROPOSED SYSTEM:
v In
this paper, we further study network-coded third party information exchange
with the objective of minimizing the total transmission cost. Different from
previous works, we aim to propose an efficient and scalable transmission scheme
which can tell the exact number of packets that should be sent by each node.
Besides that, we also aim to design an efficient deterministic encoding
strategy, which not only can achieve good performance, but also has a very low
encoding/decoding complexity (e.g., with a very low coding field size). We call
a deterministic coding and transmission scheme feasible if it allows all the
nodes to eventually deduce all the global CSI, and we call a feasible solution optimal
if it also minimizes a certain cost metric.
v The
goal of this paper is to develop constructive, feasible solutions (including
how many packets for each node to transmit and how they are encoded and
decoded) that are optimal with respect to the total transmission cost.
v We
construct two efficient and feasible transmission schemes, and prove that the
proposed two schemes will achieve optimality (with respect to the total
transmission cost) under two specific scenarios.
v A
deterministic encoding strategy is designed and can be used in combination with
the proposed schemes to ensure the successful deduction of all desired packets
at each node. Different from previous works on minimizing transmission cost,
the proposed encoding strategy is based on XORs coding over only GF(2), which
has very low complexity.
v We
also develop a practical distributed transmission protocol that enables the
proposed two transmission schemes to be operated in a distributed and hence
scalable manner.
ADVANTAGES
OF PROPOSED SYSTEM:
ü Common
control channel is available which allows reliable broadcast by any node to all
the other nodes.
ü We
formulate the problem of minimizing the total transmission cost as an integer
linear programming (ILP) problem. We show that the optimal solution is one of
“water-filling” nature, and a node with lower transmission cost should
therefore send more packets than the node with higher transmission cost.
ü The
deterministic encoding strategy helps in achieving good performance
ü The
system is optimal with respect to the total transmission cost.
ü The
system also ensures the successful deduction of all desired packets at each
node.
SYSTEM ARCHITECTURE:
SYSTEM
REQUIREMENTS:
HARDWARE REQUIREMENTS:
Ø
System : Pentium IV 2.4 GHz.
Ø
Hard Disk :
40 GB.
Ø
Floppy Drive : 1.44
Mb.
Ø
Monitor : 15
VGA Colour.
Ø
Mouse :
Logitech.
Ø Ram : 512 Mb.
SOFTWARE
REQUIREMENTS:
Ø Operating system : Windows
XP/7/LINUX.
Ø Implementation : NS2
Ø NS2 Version : NS2.2.28
Ø Front
End : OTCL (Object Oriented
Tool Command Language)
Ø Tool : Cygwin (To simulate in Windows OS)
REFERENCE:
Xiumin Wang, Chau Yuen, Tiffany Jing Li, Wentu Song,
and Yinlong Xu, “Minimizing Transmission Cost for Third-Party Information
Exchange with Network Coding”, IEEE TRANSACTIONS ON MOBILE COMPUTING, VOL. 14,
NO. 6, JUNE 2015.
