This paper presents a model for analyzing the performance of transmission strategies in multihop packet radio network where each station has adjustable radius. A larger radius will increase probability finding receiver desired direction and contribute bigger progress if is successful, but it also higher collision with other transmissions. The converse true shorter range. We illustrate our by comparing three strategies. Our results show that can achieve better suitably controlling One...

The ad hoc network is a temporary wireless system without fixed (wired or wireless) infrastructure. Many clustering algorithms have been proposed to partition mobile users into clusters support routing and management. Most previous studies, however, focus on algorithm design, lacking an overall evaluation of overheads. We design multiple access scheme for the broadcast control messages, propose new access-based protocol (ABCP) whose cluster formation heavily influenced by outcome access. By...

Broadband packet switches handling an asynchronous-time-division-multiplexing type protocol format, e.g. Starlite, can achieve buffer efficiencies by sharing buffers between output ports. It is shown that the number of required with sharing, for random traffic, would be overestimated as much 30% at 90% traffic load if negative correlations naturally exist, this streams destined different ports were not taken into account. In general, discrepancy increases increases, and decreases switch size...

Mixed continuous-bit-rate (CBR) and bursty traffic contending for transmission on any output line of a broadband switch based the asynchronous transfer mode (ATM) is modeled as superposition from number independent random binary sources. With use recursive algorithm, complete queuing analysis presented. The queue length distribution, delay cell loss probability finite buffer system are exactly calculated. Cases considered analyzed include: priority CBR traffic, absolute DS1/DS3 emulation or...

In this paper, we analyze the throughput of IEEE 802.11 DCF scheme using RTS/CTS access mechanism in multi-hop ad hoc networks. The mathematical analysis is much more involved than that a single-hop network due to hidden node problem. A realistic carrier sense range considered paper. impact parameters, such as number stations, packet size, and range, also considered. Simulation results show good agreement with analytical results.

This paper studies the impact of node density on end-to-end throughput and delay in multi-hop wireless networks. In existing work, each packet is most assumed to be relayed through one cell at hop progress approximated by square root a area, which does not correspond actual real network. this paper, we calculate taking into account effect (i.e., number nodes within transmission range node), obtain required count for path. Based result, further discuss scaling relations between The effects...

With the vigorous development of industrial automation and Internet things, transmission data is more dependent on immediacy, so network devices have higher requirements for time synchronization accuracy. The clock source common provided by transistor oscillator in server, but will change with factors such as aging temperature, it cannot be guaranteed that server work at same frequency. Time can achieved technologies IRIG-B, NTP, or IEEE 1588 (PTP), hardware cost building IRIG-B high, NTP...

In this paper, we study the issues of medium access control (MAC) mechanisms for multi-hop wireless networks with directional antennas. Specifically, explore location-dependent carrier sensing problem and interference caused by minor lobes Existing solutions to antenna MAC problems rarely account impact typically assume that neighboring nodes' locations are known a priori. As result, they not applicable practical systems or mobile nodes. propose Reservation-based Directional (RDMAC) protocol...

In the industrial Internet of Things, network time protocol (NTP) can be used for synchronization, allowing machines to run in sync so that take critical actions within 1 ms. However, commonly NTP mechanism does not into account packet travel over a link is time-varying, which causes make incorrect synchronization decisions. Therefore, this paper proposed low-cost modification with clock skew compensation and adaptive adjustment, difference between client server controlled ms wired...

Abstract Cities worldwide have planned and implemented large‐scale wireless mesh network (WMN) deployments. These deployments are expected to provide broadband mobile access the Internet at a low cost user. This paper considers fairness problem affecting nodes in multihop WMNs. Many existing approaches coping with unsuitable because they necessitate modifications IEEE 802.11 MAC protocol or node queueing operations. Such require change hardware/firmware every WMN. Thus, these less favorable...

A number of performance issues associated with real-time traffic-monitoring schemes are addressed. These will likely be used in broadband packet-transport-based networks such as ISDN (B-ISDN) asynchronous transfer mode (ATM). The an appropriate framework for scheme comparisons, control actions based on traffic-monitoring, and how traffic parameters (that could enter strongly into service contracts between the network users) should best specified treated overview summary. Some more commonly...

Abstract Previous studies on the performance of synchronous self‐routeing packet switches have assumed that input traffic is random, i.e. there no correlation between adjacent arrivals. This assumption generally not valid in data communication environment (e.g. host‐to‐host communication) where a file transfer usually generates string correlated packets. The consequence random greatly underestimates buffer requirement switch. In this paper, we model each stream as binary source first step to...

The femtocell base station is a low power and cost small in the customer premise. It connects to core network via cable, DSL or similar backhaul technology. In this paper, we focus on how received signal quality can be improved by deploying stations WiMAX system. We propose suburban model analyze potential improvement SINR when using different channel assignment schemes deployment densities of within macrocell. simulation results show that enhance large number macrocells,...

In this paper, we study how the downlink received signal quality and throughput will be affected by deploying Open Subscriber Group (OSG) Femtocell [1] using Location-Dependent Power Setting (LDPS) scheme with spectrum allocation (1, 3, 3) in next generation mobile network. The LDPS aims to use a suitable power for femtocell base station maintains its indoor user coverage. design of mandating users connect femtocells ensures transmission reduces load macrocell stations. Furthermore,...

Recent research on router architectures focuses speeding up the time-consuming routing-lookup procedure by elaborate algorithms and data structures to match ever-increasing wire-speed of fiber links. However, we observed strong temporal locality in traffic traces collected from two TANet backbone routers. Thus, a routing cache, which is used reuse previous results, can significantly offload module. In this paper, first introduce our analysis. Then investigate efficiency several cache...

Abstract The performance of backoff scheme plays an important role in designing efficient Medium Access Protocols for ad hoc networks. In this paper, we propose adaptive and evaluate the proposed mechanism devised by us grants a node access to channel based on its probability collision transmitted frame comparison nodes two‐hop contention area. We use both analytical model simulation experiments our network. results show that protocol exhibits significant improvement power saving, end‐to‐end...

To evaluate the behavior of TCP on a path with wireless link, we build wireline-wireless network model, and assume link is bottleneck which causes packets to be buffered at interface buffer. A reliable layer protocol assumed hides fluctuations medium from TCP. We first model channel Markov chain use matrix geometric method packet loss probability. then analyze long-term steady-state send rate throughput connection.

In order to ensure an efficient network control for mobile ad hoc networks, nodes are usually aggregated into clusters provide a convenient framework. However, important issue on how properly assign channels over multi-cluster structure has not been studied in depth. this paper, we first propose new clustering algorithm facilitate subsequent channel assignment. Each cluster one clusterhead. Between clusterheads, there gateways that relay information and help eliminate the hidden terminal...

In MANETs querying routes by blind flooding often incurs redundancy, contention, and collision. These phenomena are known as the broadcast storm problem, which will degrade network performance. To alleviate we propose a controlled mechanism, called zone-based (ZCF), to improve efficiency of rebroadcast in route discovery phase. quickly repair broken link close destination node without enlisting service source node, also one-hop recovery mechanism locally route, thereby minimizing routing...

There has been a growing interest in multihop wireless ad hoc networks recent years. Previous studies have shown that, when using the IEEE 802.11 DCF protocol network, maximum end-to-end good put is achieved all nodes are within transmission range of each other. The main reason that channel spatial reuse factor gained from network does not match increase additional hops packet needs to travel network. For its MAC frame delivery capacity approximately fixed at value dependent on factor. If...

In many applications of wireless sensor networks, nodes are required to move around complete their job assignments, e.g., collecting data or exploring the environment. those cases, location is an important information. previous localization studies, it that certain anchor be fixed in locations provide references. this paper, we propose a novel algorithm, which can derive other with high accuracy environment where all mobility and without requiring existence fixed-location nodes.