On limits of embedded systems in network packet processing

The paper deals with a measurement of single-hop one way packet delay on embedded systems used for networking. The single-hop one way packet delay is essential parameter when we need to process packets with strict delivery time constrains. Comparison of different approaches to single-hop one way packet delay measurements is presented in this work along with discussion about strong and weak points in specific measurement approach. The impact of different types of system load and number of CPU cores are also covered by presented results. The presented results of measurement single-hop one way packet delay in embedded Linux system show that for the specific system configuration the packet processing delay depends (in different ways) on system load and network stack load

Stability conditions for a decentralised medium access algorithm: single- and multi-hop networks

We consider a decentralised multi-access algorithm, motivated primarily by the control of transmissions in a wireless network. For a finite single-hop network with arbitrary interference constraints we prove stochastic stability under the natural conditions. For infinite and finite single-hop networks, we obtain broad rate-stability conditions. We also consider symmetric finite multi-hop networks and show that the natural condition is sufficient for stochastic stability

Source Coding for a Multihop Network

Summary form only given. In this paper, we bound the rate-distortion region for a four-node network. The results are the first known expansion of rate-distortion theory from single-hop networks (every source has a direct connection to each of its destinations), to multihop networks, which allow intermediate nodes. While single-hop network source coding solutions may be applied in multihop networks, such applications require explicit rate allocation for each source-destination pair, and the resulting solutions may be suboptimal. We therefore tackle the multihop network source coding problem directly using a diamond network

Multi-hop Cooperative Relaying for Energy Efficient In Vivo Communications

This paper investigates cooperative relaying to support energy efficient in vivo communications. In such a network, the in vivo source nodes transmit their sensing information to an on-body destination node either via direct communications or by employing on-body cooperative relay nodes in order to promote energy efficiency. Two relay modes are investigated, namely single-hop and multi-hop (two-hop) relaying. In this context, the paper objective is to select the optimal transmission mode (direct, single-hop, or two-hop relaying) and relay assignment (if cooperative relaying is adopted) for each source node that results in the minimum per bit average energy consumption for the in vivo network. The problem is formulated as a binary program that can be efficiently solved using commercial optimization solvers. Numerical results demonstrate the significant improvement in energy consumption and quality-of-service (QoS) support when multi-hop communication is adopted

Parameterized Verification of Safety Properties in Ad Hoc Network Protocols

We summarize the main results proved in recent work on the parameterized verification of safety properties for ad hoc network protocols. We consider a model in which the communication topology of a network is represented as a graph. Nodes represent states of individual processes. Adjacent nodes represent single-hop neighbors. Processes are finite state automata that communicate via selective broadcast messages. Reception of a broadcast is restricted to single-hop neighbors. For this model we consider a decision problem that can be expressed as the verification of the existence of an initial topology in which the execution of the protocol can lead to a configuration with at least one node in a certain state. The decision problem is parametric both on the size and on the form of the communication topology of the initial configurations. We draw a complete picture of the decidability and complexity boundaries of this problem according to various assumptions on the possible topologies.Comment: In Proceedings PACO 2011, arXiv:1108.145

Mode Selection for Multi-Hop Cellular Networks with Mobile Relays

Multi-hop Cellular Networks using Mobile Relays (MCN-MRs) are being investigated to help address certain limitations of traditional single-hop cellular communications. A key element of MCN-MR technologies is the mode selection scheme that selects the most adequate connection mode (traditional single hop cellular or multi-hop link) for each transmission. This paper proposes a novel mode selection scheme that uses context information to select the connection mode, and can adapt its decisions to the operating conditions. This study shows that the proposed scheme outperforms distance-based mode selection schemes, and helps improving the MCN-MR performance with respect to single-hop cellular communications