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Network Coding for Mobile Devices - Systematic Binary Random Rateless Codes

In this work we consider the implementation of Random Linear Network Coding (RLNC) on battery constrained mobile devices with low computational capabilities such as; sensors, mobile phones and Personal Digital Assistants (PDAs). It is non-trivial to create an efficient implementation of RLNC which is needed to ensure high throughput, low computational requirements and energy consumption. As a consequence there does not, to the best of our knowledge, exist any such implemen- tation for mobile device that allow for throughput close to what can be achieved in e.g. Wireless Local Area Network (WLAN). In this paper we propose to base RLNC on the binary Galois field and to use a systematic code. We have implemented this approach in C++ and Symbian C++ and achieve synthetic encoding/decoding throughput of up to 40/30 MB/s on a Nokia N95-8GB mobile phone and 1.5/1.0 GB/s on a high end laptop. Index Terms—Mobile devices, Network coding, Reliable Mul- ticast. I. INTRODUCTION A large body of existing literature (1) treats the theoretical benefits of Network Coding (NC). However, the costs of implementing NC in terms computational overhead, memory consumption or network usage is often not considered. In this work we consider the implementation of RLNC on mobile bat- tery constrained devices with low computational capabilities, such as sensors, mobile phones or PDAs. The computations performed using RLNC is based on finite fields arithmetic also known as Galois fields. From a coding perspective the field size, q, used should be large to ensure that coded packets are linearly independent, additionally increasing the size of the field elements is advantageous as this reduces the number of

Kodo: an open and research oriented network coding library

This paper introduces theKodo network coding library. Kodo is an open source C++ library intended to be used in practical studies of network coding algorithms. The target users for the library are researchers working with or interested in network coding. To provide a research friendly library Kodo provides a number of algorithms and building blocks, with which new and experimental algorithms can be implemented and tested. In this paper we introduce potential users to the goals, the structure, and the use of the library. To demonstrate the use of the library we provide a number of simple programming examples. It is our hope that network coding practitioners will use Kodo as a starting point, and in time contribute by improving and extending the functionality of Kodo.

Implementation and Performance Evaluation of Network Coding for Cooperative Mobile Devices

In this work a performance evaluation of network coding for cooperative wireless networks is carried out. Implementing network coding on commercially available mobile devices, the performance is presented in terms of throughput, delay and energy consumption. In contrast to purely cellular systems, where the mobile devices are only connected to the base station, in cooperative wireless networks, the mobile device, in addition to the cellular communication, establishes short range links to neighboring mobile devices within its proximity. In prior work it has been shown that the newly formed cooperative cluster, also referred as wireless grid, can offer each participating mobile device a better performance in terms of data rate, delay, robustness, security, and energy consumption in contrast to any stand alone device. To improve the performance within the cooperative cluster even more, network coding seems to be a promising technology as it decreases the number of packets to be interchanged among cooperative mobile devices leading to a decreased packet delay. The energy saved by fewer packet transmissions is confronted with the energy needed to carry out the network coding and related overhead. The findings of this paper show that network coding is always beneficial in terms of throughput and delay for the cooperative cluster.

Novel concepts for device-to-device communication using network coding

Device-to-device communication is currently a hot research topic within 3GPP. Even though D2D communication has been part of previous ad hoc, meshed and sensor networks proposals, the main contribution by 3GPP is that the direct communication among two devices is carried out over a dynamically assigned, licensed spectrum; thus, it is under full control of the cellular network. D2D communication creates a market potential for new services, new approaches to efficient spectrum use, and security concepts. This is especially true if D2D communication is extended to larger communication groups organized in meshed clusters. In this article, we discuss the potential and shortcomings of D2D communication as proposed today, advocating for the use of network coding as an enabling technology for enhanced security and communication efficiency using the PlayNCool and CORE protocols as key examples to deliver smarter D2D systems.

Synchronized multimedia streaming on the iPhone platform with network coding

This paper presents the implementation of synchronized multimedia streaming for the Apple iPhone platform. The idea is to stream multimedia content from a single source to multiple receivers with direct or multi-hop connections to the source. First we look into existing solutions for video streaming on the iPhone for point-to-point architectures. After acknowledging their limitations, we propose a solution based on network coding to efficiently and reliably deliver the multimedia content to many devices in a synchronized manner. Then we introduce an application that implements this technique on the iPhone. We also present our testbed which consists of 16 iPod Touch devices to showcase the capabilities of our application.

Lean and mean: network coding for commercial devices

With its ability to reduce the number of transmissions in lossy networks as well as its potential to simplify the design and required signaling of communication protocols, network coding has emerged as an attractive solution to harness the power of wireless and cooperative networks in order to provide higher throughput and lower energy expenditure. This article shows that network codings complexity is not an issue for current mobile devices even without hardware acceleration. We provide real-life measurements of energy savings gains of two design styles of network coding, namely, inter- and intra-session network coding using commercial platforms, including Open-Mesh routers and various mobile phones. We demonstrate that the energy per bit invested in coding/decoding operations can be several orders of magnitude smaller than that used for transmission/reception, while also maintaining processing speeds as high as several hundreds of Mb/s or even several Gb/s depending on the device and coding configuration used.

Cautious view on network coding — From theory to practice

Energy consumption has been mostly neglected in network coding (NC) research so far. This work investigates several different properties of NC that influence the energy consumption and thus are important when designing NC systems for battery-driven devices. Different approaches to the necessary implementation of coding operations and Galois fields arithmetic are considered and complexity expressions for coding operations are provided. We also benchmark our own mobile phone implementation on a Nokia N95 under different settings. Several NC strategies are described and compared, furthermore expressions for transmission times are developed. It is also shown that the use of NC introduces a tradeoff between reduction in transmission time and increase in energy consumption.

Mobile Clouds: The New Content Distribution Platform

This paper discusses the future of content distribution among mobile devices forming the so-called mobile clouds. This paper introduces the current-technology-based problems of the approach, but also highlights its future potential. One core element of this paper is the technical development in this area and the social paradigm that will be used to create cooperation among users. We conclude that the future of mobile clouds will be in novel technologies such as network coding as well as in combination with social networks in order to boost cooperation among users as well as connect people over the shared content.

CATWOMAN: Implementation and Performance Evaluation of IEEE 802.11 Based Multi-Hop Networks Using Network Coding

This paper investigates the performance of network coding for an IEEE802.11 enabled meshed network. By means of basic setups the impact of the medium access control in combination with network coding is investigated. In contrast to prior work the network coding approach is tailored to commercial WiFi hardware without any special tweaks. The implementation of network coding is done on top of an existing routing scheme known as B.A.T.M.A.N. which has some inherent advantages to support network coding. We present schemes to utilize the B.A.T.M.A.N. routing to detect coding opportunities. One finding is that the performance gain for the well known Alice and Bob scenario using network coding is 60% compared to a pure relaying scheme. The software used in the presented measurement campaign is made publicly available.

PictureViewer - A mobile application using network coding

This paper looks into the implementation details of network coding for a mobile application running on commercial mobile phones. The mobile application coined PictureViewer can convey pictures from one source device to many neighboring devices using WiFi. The advantage of network coding in this context is that the source devices only needs a minimal amount of knowledge about the targets received packets and therefore only a minimal amount of feedback is needed to ensure reliable data delivery. The implemented network coding algorithms are tailored to be fast and energy efficient on commercial mobile phones. The goal of the paper is therefore to investigate those algorithms and to demonstrate that network coding can be deployed on state of the art mobile phones.