Random network coding on the iPhone: fact or fiction?

ABSTRACT

In multi-hop wireless networks, random network coding represents the general design principle of transmitting random linear combinations of blocks in the same "batch" to downstream relays or receivers. It has been recognized that random network coding in multi-hop wireless networks may improve unicast throughput in scenarios when multiple paths are simultaneously utilized between the source and the destination. However, the computational complexity of random network coding, and its energy consumption implications, may potentially limit its applicability and practicality in mobile devices. In this paper, we present our real-world implementation of random network coding on the Apple iPhone and iPod Touch mobile platforms, and offer an in-depth investigation with respect to the difficulties towards such an implementation, the limitations of the ARM processor and the hardware platform, as well as our hand-tuning efforts to maximize coding performance on the iPhone platform. With our implementation deployed on both the iPhone 3G and the second-generation iPod Touch, we report its coding performance, energy consumption rates, as well as CPU usage with multimedia streaming.

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.4 PERFORMANCE OF SYSTEMS

Additional Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.4 Distributed Systems

General Terms:
Algorithms, Experimentation, Performance

Keywords:
P2P systems, iPhone, network coding