The stability of a queueing network with interdependent servers is considered. dependency among the described by definition their subsets that can be activated simultaneously. Multihop radio networks provide motivation for consideration this system. problem scheduling server activation under constraints imposed studied. performance criterion policy its throughput characterized region, is, set vectors arrival and service rates which system stable. A obtained optimal in sense region superset...

The wireless networking environment presents formidable challenges to the study of broadcasting and multicasting problems. After addressing characteristics networks that distinguish them from wired networks, we introduce evaluate algorithms for tree construction in infrastructureless, all-wireless applications. performance metric used broadcast multicast trees is energy-efficiency. We develop incremental power algorithm, adapt it operation as well. This algorithm exploits nature...

The design of a packet radio network must reflect the operational requirements and environmental constraints to which it is subject. In this paper, we outline those features that distinguish High Frequency (HF) Intra Task Force (ITF) Network from other networks, present concept for encompasses organizational structure, waveform design, channel access. survivability achieved through use distributed control frequency hopping spread-spectrum signaling. We demonstrate how execution fully Linked...

In this paper we consider the problem of organizing a set mobile, radio-equipped nodes into connected network. We require that reliable structure be acquired and maintained in face arbitrary topological changes due to node motion and/or failure. also such achieved without use central controller. propose develop self-starting, distributed algorithm establishes maintains architecture. This is especially suited needs HF Intra-Task Force (ITF) communication network, which discussed paper.

Consider N parallel queues competing for the attention of a single server. At each time slot queue may be connected to server or not depending on value binary random variable, connectivity variable. Allocation at slot; is based information and lengths only. end slot, service completed with given fixed probability. Such queueing model appropriate some communication networks changing topology. In case infinite buffers, necessary sufficient conditions are obtained stabilizability system in...

We consider a communication system in which status updates arrive at source node, and should be transmitted through network to the intended destination node. The are samples of random process under observation, as packets, also contain time stamp identify when sample was generated. age information available node is elapsed, since last received update In this paper, we model source-destination link using queuing theory, assume that it takes successfully transmit packet an exponentially...

In this paper, we introduce a cross-layer design framework to the multiple access problem in contention-based wireless ad hoc networks. The motivation for study is twofold, limiting multiuser interference increase single-hop throughput and reducing power consumption prolong battery life. We focus on next neighbor transmissions where nodes are required send information packets their respective receivers subject constraint signal-to-interference-and-noise ratio. solved via two alternating...

A comprehensive study of the problem scheduling broadcast transmissions in a multihop, mobile packet radio network is provided that based on throughput optimization subject to freedom from interference. It shown NP complete. centralized algorithm runs polynomial time and results efficient (maximal) schedules proposed. distributed achieves same then The maximal broadcasting zone every slot.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Information theory has not yet had a direct impact on networking, although there are similarities in concepts and methodologies that have consistently attracted the attention of researchers from both fields. In this paper, we review several topics related to communication networks an information-theoretic flavor, including multiaccess protocols, timing channels, effective bandwidth bursty data sources, deterministic constraints datastreams, queuing theory, switching networks.

The standard discrete-time slotted ALOHA system with a finite number of buffered terminals is considered. stability (ergodicity) region for this known only the case two and any symmetric terminals. studied by means simple concept dominance. It shown that can be obtained in way. Lower (inner) bounds are an arbitrary tighter than ones already known. A similarity between these results achievable no-feedback collision channel pointed out suggests connection problems.< <ETX...

We consider a system in which random status updates arrive at source node, and should be transmitted through wireless network to the intended destination node. The are samples of process, as packets, containing time stamp identify moment sample was generated. it takes successfully transmit packet is modeled an exponentially distributed service time. update age receiver elapsed since last received In this paper, we analyze case that node has capability manage arriving decide packets will...

As jobs arrive they have to be routed one of two similar exponential servers. It is shown that if the queue lengths at both servers are observed then Optimal decision route shorter queue, whereas lenths not it best alternate between queues, provided initial distribution sizes same. The optimality these routing strategies independent statistics job arrivals.

In this paper, a novel cognitive multiple-access strategy in the presence of cooperating relay is proposed. Exploiting an important phenomenon wireless networks, source burstiness, utilizes periods silence terminals to enable cooperation. Therefore, no extra channel resources are allocated for cooperation and system encounters bandwidth losses. Two protocols developed implement proposed strategy. The maximum stable throughput region delay performance characterized. results reveal that...

We consider the system where a source randomly generates status update messages and transmits them via network cloud to intended destination. These message can take different times traverse network, which we model as exponential service times, may result in packets reaching destination out of order, rendering some earlier transmissions obsolete. analyze age for such system, show that it tracks well with simulation results.

This paper focuses on status age, which is a metric for measuring the freshness of continually updated piece information (i.e., status) as observed at remote monitor. In paper, we study system in sensor sends random updates over dynamic network to For this system, consider impact having messages take different routes through age. First, with plentiful resources many nodes that can provide numerous alternate paths), so packets need not wait queues each node multihop path. modeled single queue...

In this paper, we introduce a new performance metric in the framework of status updates that will refer to as Age Incorrect Information (AoII). This deals with shortcomings both (AoI) and conventional error penalty functions it neatly extends notion fresh “informative” updates. The word informative context refers bring correct information monitor side. After properly motivating metric, aim minimizing its average, formulate Markov Decision Process (MDP) transmitter-receiver pair scenario...

We consider a real-time status update system consisting of source-destination network. A stochastic process is observed at the source, and samples, so called updates, are extracted random time instances, delivered to destination. In this paper, we expand concept information ageing by introducing Cost Update Delay (CoUD) metric characterize cost having stale introduce Value Information (VoIU) that captures reduction CoUD upon reception an update. The importance VoIU lies on its tractability...

Information age is a recently introduced metric to represent the freshness of information in communication systems. We investigate minimization wireless network and propose novel approach optimizing scheduling strategy deliver all messages as fresh possible. Specifically, we consider set links that share common channel. The transmitter at each link contains given number packets with time stamps from an source generated them. address transmission problem objective minimizing overall age. This...

We study the age of information, which is a measure freshness continually updated piece information as observed at remote monitor. The metric has been studied for variety different queueing systems, and in this paper, we introduce packet deadline control mechanism to its impact on average an M/M/1/2 system. analyze system cases fixed random exponential derive closed-form expressions age. also expression optimal case. Our numerical results show relationship performance that M/M/1/1...

We present our vision for a departure from the established way of architecting and assessing communication networks, by incorporating semantics information, defined not necessarily as meaning messages, but their significance, possibly within real-time constraint, relative to purpose data exchange. argue that research efforts must focus on laying theoretical foundations redesign entire process information generation, transmission, usage networked systems in unison developing advanced semantic...

The focused attention of the community on energy issues in study and design wireless networks has spurred a great deal research subject. In this article brief overview is provided what constitutes major efficiency ad hoc networks. Emphasis placed key conceptual points, which are then illustrated case multicasting connection-oriented traffic.

In this paper we introduce power control as a solution to the multiple access problem in contention-based wireless ad-hoc networks. The motivation for study is two fold, limiting multi-user interference increase single-hop throughput, and reducing consumption battery life. We focus on next neighbor transmissions where nodes are required send information packets their respective receivers subject constraint signal-to-interference-and-noise ratio. solved via alternating phases, namely...

A new architecture for mobile radio networks, called the linked cluster architecture, is described, and methods implementing this using distributed control techniques are presented. We illustrate how fully can be combined with hierarchical to create a network that robust respect both node loss connectivity changes. Two algorithms presented deal formation linkage of clusters activation links. To study performance our structuring algorithms, simulation model was developed. The use Simula...