Route selection for data packets in a tactical packet radio network using integrated voice and data transmissions

We introduce a new medium access control (MAC) protocol named PDMA (poll-before-data multiple access). Most prior MAC protocols aimed at avoiding collisions of data packets in networks with hidden terminals are sender-initiated, in that the sender transmits a short request to send (RTS) asking the receiver for permission to transmit. In contrast in PDMA, when a data packet arrives at the receiver, the receiver sends a ready-to-receive-and-transmit (RT2) packet stating the identifiers of a specific sender and receiver. A node receiving an RT2 packet addressed to it as a sender is enabled to send a data packet if it has one; otherwise, if the sender specified in the RT2 is quiet, the receiver specified in the RT2 sends a clear-to-send (CTS) packet, enabling the sender of the RT2 to send its own data packet free of collisions. PDMA is shown to avoid the collision of data packets with any type of packet. An analytical model is used to show that PDMA achieves higher throughput than prior collision-avoidance protocols for wireless networks, namely MACA-BI, FAMA NCS, and MACA. Average delays in PMA are also shown to be shorter than those in CSMA.

Existing packets scheduling algorithms designed for energy-efficient wireless networks ignore important features of periodic packets, thereby being inadequate for periodic packets with energy constraints. To remedy this problem, I present in this paper an approach to scheduling periodic packets in wireless networks subject to both timing and energy constraints. I propose a necessary and sufficient feasibility check for a set of periodic packets to be transmitted over a wireless link. Next, I develop an algorithm to schedule periodic packets (or ESPP for short) over a wireless link. The ESPP algorithm aims at minimizing energy dissipation of periodic packets without missing deadlines of periodic packets. I show through simulation studies that ESPP can significantly reduce energy consumption of wireless networks by an average of 46.4% while guaranteeing timing constraints of periodic packets.

The energy-efficient and reliable delivery of data packets in resource constraint underwater wireless sensor networks (UWSNs) is one of the key considerations to enhance the network lifetime. The traditional re-transmissions approach consumes the node battery and increases the communication overhead, which results in congestion and affects the reliable data packet delivery in the network. To ensure the reliability and conserve the node battery, in this paper, we propose adaptive forwarding layer multipath power control routing protocol to reduce the energy dissipation, achieve the data reliability and avoid the energy hole problem. In order to achieve the reliability, tree based topology is exploited to direct multiple copies of the data packet towards the surface through cross nodes in the network. The energy dissipation is reduced by a substantial amount with the selection of low noise path between the source and the destination including the information of neighbors of the potential forwarder node. Extensive simulation results show that our proposed work outperforms the compared existing scheme in terms of energy efficiency and packet received ratio (PRR).

IP transition is one of the innovative and challenging areas for the researchers in the recent times. Presently, the transition scheme in Advanced Dual Stack Transition Mechanism (ADSTM) is consuming more time in wireless networks, which impede in general performance of the network. This paper discusses the fast transition of IPV4 packets to IPV6 packets in the Wireless networks via ADSTM. To enhance the performance of ADSTM in wireless network, it is incorporated with the Super Fast Packet Transmission Algorithm (SFTPA). In SFTPA instead of Internet Protocol Header Compression (IPHC) algorithm it is replaced with Robust Header Compression (ROHC) algorithm for better compression, which will reflects in the fast transmission of data packets in Wireless Networks. Simulation experiments were conducted on both the DSTM and ROHC individually and later on their results were merged for the better performance. This work proves that SFTPA has performed better than Fast Packet Transition Algorithm (FPTA) without hampering the Quality-of-Service.

Packet radio technology is currently used in a wide range of tactical military communication systems, including SINCGARS, EPLARS, and NTDR, for the transfer of data based messages across the battlefield. The DARPA GloMo program is also investigating the use of this technology for the transfer of multimedia voice, data and video traffic among dismounted infantry users in ad hoc mobile radio networks. A key aspect of the GloMo program is the development of adaptive protocols that minimize energy consumption and maximize the battery life of a user's handheld terminal. Under sponsorship from DARPA and internal research and development funding from ITT Industries, we have developed a unique set of algorithms to minimize energy consumption by adaptation of physical and link layer protocol parameters within a packet radio network. This paper presents an overview of these algorithms and then presents a design and modeling approach, based upon Taguchi (1984, 1987) techniques, for the optimization of these algorithms. We present a metric that optimizes performance as a function of the number of successful information bits at the output of the decoder per unit of energy transmitted. When applied to hand-held or portable, packet radio communication equipment, this metric provides improved performance with respect to battery life and signal intercept performance. OPNET models are used to run a set of matrix experiments to arrive at an optimized set of design parameters for operation of theses adaptive transmission protocols in a tactical environment.

Mobile wireless networks have been gaining popularity since the turn of the new millennium as they enable communication to take place without fixed communication infrastructure. This form of communication, which has been made possible by radio links proved its usefulness during emergency medical rescues such as an Ebola pandemic, battlefield communications or other emergency situations, where quick communication is of paramount importance. Nature-inspired algorithms such as AntHocNet, AntSense, among other ant inspired techniques, have been mimicked in solving the communication challenges in wireless networks, but they focus mostly on the ‘next-hop’ in determining routing of data packets from the source to the destination, which tends to suffer from congestion-related problems. Ant routing methods focus more on next-hop neighbours when choosing the shortest path which might have many data packets and are prone to congestion. Focusing on the next-hop neighbours poses a challenge of having other nodes that end up being congested. This problem of routes being heavily used, often decreases throughput rates, leading to the proposed Queuing Ant Colony System (QUACS) which is a bio-inspired, complementing the queuing optimisation approach in routing of data packets across the network. The results of simulations show that QUACS performs better in throughput, packet delivery ratio, end-to-end delay and communication overhead than other ant routing algorithms. This study is particularly beneficial in the ad hoc networks where the QUACS routing method can greatly assist in faster communication and evacuation in emergency for treatment of patients during emergency medical rescue operations.

Hybrid wireless mesh networks are suitable for complex environment communication in coal mine. Mesh clients with application service and routing function in hybrid wireless mesh networks can form a highly robust hybrid network with mesh routers. The processes of nutrient flux transfer and path choice in Physarum network are similar to data transmission and routing selection in hybrid wireless mesh networks. In this article, we use Physarum-inspired autonomic optimization model to design a Physarum-inspired multi-parameter adaptive routing protocol to improve the service quality of coal mine hybrid wireless mesh networks. Physarum-inspired multi-parameter adaptive routing protocol has achieved distributed routing decision by drawing the hybrid wireless mesh network parameters into Poisson’s equation of Physarum-inspired autonomic optimization model to measure the quality of link and implements two adjustment strategies to make the protocol more adaptive. The resource-dependent adjustment, which considers the irreversible energy consumption and recoverable buffer occupation, makes the energy consumption problem prominent when there is a lack of energy. The position-dependent adjustment makes routing decision efficient according to the load of different positions, which is caused by many-to-one data transmission model in coal mine. Based on NS2, simulation experiments are performed to evaluate the performance of Physarum-inspired multi-parameter adaptive routing protocol, and the results are compared with those of ad hoc on-demand distance vector, HOPNET, ANT-DSR, and Physarum-inspired routing protocols. The experimental results show that the route path selected by Physarum-inspired multi-parameter adaptive routing protocol is better than those selected by the other four protocols in the performance of average end-to-end delay and delivery ratio. The balance of energy consumption and network load is achieved and the network lifetime is effectively prolonged when using Physarum-inspired multi-parameter adaptive routing protocol.

A real-time flood-routed voice protocol for fibre optic local area networks

We address an issue of channel sharing among users by using a random assignment/transmitter-oriented (RA/T) code scheme which permits the contention mode only in the transmission of a header while avoiding collision during the data packet transmission. Once the header is successfully received, the data packet is ready for reception by switching to one of the programmable matched-filters. But the reception may be blocked due to a limited number of matched-filters so that this effect is taken into account in our analysis. We also consider an acknowledgment scheme to notify whether the header is correctly detected and the data packet can be processed continuously, which aims at reducing the interference caused by unwanted data transmission. For a realistic analysis, we integrate the detection performance at the physical level with the channel activity at the link level through a Markov chain model. It is shown that compared to classical code-division multiple-access (CDMA) systems, a reduction in the receiver complexity of a half is allowed by choosing a proper number of RA/T codes without losing the performance quality in view of the normalized throughput.

Wireless communication that provides voice only is not sufficient to support the necessity of user. In the future, the major advantage of third generation wireless communication (3G) are providing packet data communication, mobile Internet, and mobile multimedia data communication. This kind of data type requires more bandwidth to transmit data. Sometimes, the communication would be encountered the transmitting block because the new cell has no enough resource allocating to mobile station (MS or MH) in handoff. How to reduce the losing probability of data packets in wireless communication networks is important things which can raise the quality of service (QoS) and degrade the time and resource consume. In this paper, a resource reservation method is proposed to improve QoS and resource switching management to reduce data packet loss for multimedia communication at handoff operation.

In order to build a mobile ad hoc network, only some battery powered nodes are required to be deployed; no additional infrastructure is necessary. Routing, scheduling etc. algorithms for this kind of networks have to be designed in such a manner that battery power in nodes can be saved, that is, algorithms should be energy efficient. In most cases, an external priority is assigned to data packets which we have to take care. Along with that, in WEEP, we consider residual lifetime of source and destination nodes to estimate whether the current packet can be sent to destination. Moreover, if possibility of completion of a communication session is less, then more weight is given to data packets belonging to those sessions. The present article aims at reducing the number of route discovery sessions through energy efficient scheduling policy. Therefore, packets travelling through paths consisting of delicate links, are blessed with more priority than those travelling through strong wireless links. Simulation results show that performance improvement produced by WEEP is very significant compared to other protocols used to scheduling in ad hoc networks. As far as the authors know, WEEP is a unique scheduling algorithm in ad hoc network that considers expected residual lifetime of destination along with performance and fragility of a path.

Network congestion causes severe transmission performance loss. Congestion control is the key to achieve low latency, high bandwidth and high stability. Due to the high regularity of topologies, datacenter networks contain abundant resources of equal-cost paths inherently and have huge potential for high-bandwidth transmission. Taking in-network telemetry (INT) information as the congestion signal, congestion control algorithms can monitor the network based on precise link load data. Hence the INT-based algorithm is the focus of recent high-precision congestion control research. However, existing INT-based congestion control algorithms handle the single-path transmission between the sender and the receiver, which cannot make full use of the abundant equal-cost paths resources in the network. In this paper, we make the first attempt to propose a multi-path INT-based congestion control algorithm, called MPICC. Compared with the most advanced INT-based congestion control algorithm HPCC, our method realizes multi-path coordinated transmission of data packets in datacenter networks. We conduct extensive experiments under various workloads to evaluate the performance of MPICC. The experimental results show that under the condition of ensuring high throughput of end hosts, MPICC is able to use multi-path to transmit data packets, which greatly reduces the flow completion time (FCT) of the flow in the network. Specifically, under three common datacenter workloads, Cache Follower, Web Search and Web Server, MPICC reduces the average flow completion time of the network by 20.1%, 14.4%, and 39.5%, respectively, and shortens the 97th-percentile flow completion time by 39.9%, 18.9% and 57.9%, respectively.KeywordsCongestion controlIn-network telemetry (INT)Multi-pathDatacenter networksProgrammable switch

We analyse throughput-delay performance of an unslotted DS-CDMA packet radio network (PRN) using the channel load sensing protocol (CLSP) and packet-length adaptation. This paper shows that while error-correcting channel coding has not yet been effective in heavily correlated flat fading environments, adapting the length of radio packets to time-varying channel conditions is a simple adaptive technique for maintaining and improving the system performance and the energy efficiency of mobile terminals. In our modeling we study the correlation between fade duration statistics and packet length in a flat Rayleigh fading channel under the effects of imperfect power control and user mobility. The results are used to derive practical and robust adaptation mechanisms and performance characteristics. A number of numerical results is presented. This paper lays the groundwork for exploiting adaptive radio possibilities on media access control (MAC) layer in unslotted DS-CDMA PRN.

A tactical network mainly consists of software-defined radios (SDRs) integrated with programmable and reconfigurable features that provide the addition and customization of different waveforms for different scenarios, e.g., situational awareness, video, or voice transmission. The network, which is mission-critical, congested, and delay-sensitive, operates in infrastructure-less terrains with self-forming and self-healing capabilities. It demands reliability and the need to survive by seamlessly maintaining continuous network connectivity during mobility and link failures. SDR platforms transfer large amounts of data that must be processed with low latency transmissions. The state-of-the-art solutions lack the capability to provide high data throughput and incorporate overhead in route discovery and resource distribution that is not appropriate for resource-constrained mission-critical networks. A cross-layer design exploits existing resources to react to environment changes efficiently, enable reliability, and escalate network throughput. A solution that integrates SDR benefits and cross-layer optimization can perform all the mentioned operations efficiently. In tactical networks, SDR’s maximum usable bandwidth can be utilized by exploiting radios’ autonomous behavior. This paper presents a novel virtual sub-nets based cross-layer medium access control (VSCL-MAC) protocol for self-forming multihop tactical radio networks. It is a MAC-centric design with cross-layer optimization that enables dynamic routing and autonomous time-slot scheduling in a multichannel network environment among SDRs. The cross-layer coupling uses link-layer information from the hybrid of time division multiple access and frequency division multiple access (TDMA/FDMA) MAC to proactively enable distributed intelligent routing at the network layer. The virtual sub-nets based distributed algorithm exploits spectrum resources and provides call setup with persistently available k-hop route information and simultaneous collision-free transmission of voice and data. The experimental results over extensive simulations show significant performance improvements in terms of minimum control overhead, processing time in relay nodes, a substantial increase in network throughput, and lower data latency (up to 76.98%) compared to conventional time-slotted MAC protocols. The design is useful for mission-critical, time-sensitive networks and exploits multihop simultaneous communication in a distributed manner.

Smart Grid is a convergent system of the existing power grid and Information Technology (IT). In Smart Grid system, AMI (Advanced Metering Infrastructure) is a system with various sensors to evaluate data related with the usage of various utility resources such as electricity, gas, and water. In this paper, IEEE 802.15.4 MAC protocol for the AMI sensor networks is analyzed. Based on the analysis, OPNET simulator was implemented for the performance evaluation. Particularly, this paper focuses on the effect of protocol parameters to the performance. For these parameters, the simulation results are presented to achieve the most efficient usage of network under different traffic loads. Based on the performance evaluation results, it is revealed that real-time data transmission is possible if the total offered load is restricted under 50 % with 100 nodes and the offered load period from 20 to 50 % makes the best trade-off in terms of network throughput, average delay, etc.