Energy Minimization through Network Coding for Lifetime Constrained Wireless Networks

Abstract

Energy management is the key issue in the design and operation of wireless network applications like sensor networks, pervasive computing and ubiquitous computing where the network is primarily driven by battery-powered embedded devices. This paper studies network coding as an energy minimization technique. Network coding reduces the energy consumption by minimizing the number of transmissions required to communicate a given amount of information across the network. However, aggressive application of network coding adversely affects the network lifetime. We illustrate this trade off in this paper, and show that the existing throughput based network coding approaches cannot be applied to energy-constrained networks. Specifically, we address the following routing problem. Given a set of traffic demands the goal is to route the demands across the network with the objective of minimizing the total energy consumption while providing guarantees on the lifetime of individual nodes. This paper studies multi-path variation of the above routing problem. We present analytical formulations to solve the problem optimally. Evaluation results indicate that the proposed solution is 35% more energy efficient than no-networkcoding solution while still meeting required lifetime constraints.

Energy Minimization With Network Coding via Latin Hypercubes

“…Moreover, optimization algorithms for solving the link scheduling problem are investigated. In [12], authors minimize the total energy consumed in the network with lifetime constraints, by determining the traffic on each edge, assuming XOR coding. In [13], an optimization problem with rate constraint is developed to minimize energy in wireless multihop networks.…”

Network Coding-aware Lifetime Maximal routing in Multi-hop Static Wireless Ad-hoc Networks

“…But the above works assumed that the nodes were not energy-limited, which is really not the case in sensor and ad-hoc networks. The work by Gaddam et al [6] addressed this issue and network coding was used as an energy-minimization technique. They formulated the lifetime maximization problem as a linear programming (LP) problem, and showed that network coding could improve network lifetime.…”

Towards network coding enhanced routing protocols for group mobility

“…Besides, the authors in [103] point out another disadvantage of the greediness for coding opportunities. That is, although routing traffic for more coding opportunities can save the total energy consumption of the network, it causes the encoding node to deplete its energy much faster than other non-encoding nodes.…”

“…In fact, the faster energy depletion of some nodes will shorten the network lifetime. Hence, to extend the network lifetime, it is necessary to be aware of the node lifetime for routing traffic: the authors in [103] propose to adopt multi-path routing together with flow traffic splitting to distribute the traffic more evenly in the network and thus ensure the network lifetime.…”

“…In this Sub-section, we summarize in Table 2-1 how each representative XNC scheme proposed under reliable links addresses the factors illustrated above. It can be seen from the table that (1) opportunistic scheduling is widely adopted in many XNC schemes due to its simplicity; and that (2) in most centralized scheduling based XNC schemes (e.g., [85,87,103]), the routing is generally aware of the coding opportunities and the network congestion state.…”