Cooperative Forwarding Schemes Research Articles

Online Caching and Cooperative Forwarding in Information Centric Networking

Information centric networking is one of the most promising future Internet architectures to tackle the increasing network traffic by enabling in-network caching to cache popular contents. Although in-network caching reduces the network traffic by providing requested content locally to the users, several challenging issues are still unsolved. For example, identical contents are replicated in all routers along each request’s forwarding path, which incurs faster cache replacement and degrades cache utilization, and temporally cached content’s locations are not easy to track or search in the network. Besides, it is tough to correctly predict future popularity of contents and decide which contents to store. Hence, in this paper, an online caching and cooperative forwarding scheme is proposed to enhance cache utilization and to reduce network delay, as well as reduce the workload on each router. The caching problem is formulated as a Ski-Rental problem, which is a classical method for online decision making, in combination with consistent-hashing to obtain an online coordinated caching solution. The proposed request forwarding scheme is based on consistent-hashing, where every router knows the potential location of the cached copy of the requested content and thereby avoiding the unnecessary forwarding. Finally, the proposed request forwarding and caching schemes were validated by a chunk-level simulator. The simulation results show that the proposed scheme outperforms the existing algorithms in terms of content hit rate, server load, the processing load on routers, and access delay.

A Wireless Cloud Network Platform for Industrial Process Automation: Critical Data Publishing and Distributed Sensing

Wireless technologies combined with advanced computing are changing industrial communications. Industrial wireless networks can improve the monitoring and the control of the entire system by jointly exploiting massively interacting communication and distributed computing paradigms. In this paper, we develop a wireless cloud platform for supporting critical data publishing and distributed sensing of the surrounding environment. The cloud system is designed as a self-contained network that interacts with devices exploiting the time synchronized channel hopping protocol (TSCH), supported by WirelessHART (IEC 62591). The cloud platform augments industry-standard networking functions as it handles the delivery (or publishing) of latency and throughput-critical data by implementing a cooperative-multihop forwarding scheme. In addition, it supports distributed sensing functions through consensus-based algorithms. Experimental activities are presented to show the feasibility of the approach in two real industrial plant sites representative of typical indoor and outdoor environments. Validation of cooperative forwarding schemes shows substantial improvements compared with standard industrial solutions. Distributed sensing functions are developed to enable the autonomous identification of recurring cochannel interference patterns.

Uncoordinated Cooperative Multihop Forwarding in 2D Highly Dynamic Networks

This paper investigates cooperative forwarding in two-dimensional highly dynamic wireless networks. Unlike traditional coordinated cooperative forwarding schemes that require a large amount of neighborhood discovery and coordination information to be exchanged before making the forwarding decision, this paper proposes an uncoordinated cooperative forwarding scheme where each node determines whether or not to forward a received packet independently based on a forwarding probability determined by its own location, the locations of the destination, and the transmitter from which it receives the packet, without the costly or even impractical neighbor discovery and coordination process. Analytical results are derived for the successful transmission probability and the expected number of forwarding nodes involved in the cooperative forwarding process. On that basis, discussions are presented on the optimal forwarding probability design that meets a predesignated successful transmission probability target using minimum number of forwarding nodes. Simulations are conducted to evaluate the performance of the proposed scheme.

A cooperative forwarding scheme for social preference-based selfishness in mobile social networks

Most schemes in mobile social networks (MSNs) assume that nodes simply forward messages without considering selfishness. We therefore first devise social preference-based selfishness for MSNs by which nodes decide to drop or keep (forward) and replace messages to save buffer space according to the message preference and the communities of nodes. We then propose a novel cooperative forwarding scheme for social preference-based selfishness in MSNs, the social preference-aware forwarding scheme (SPF) incorporates the proposed message forwarding scheme and a buffer replacement policy for the message preference. It takes advantage of social information with the home-cell community-based mobility model. Considering the contact probability and buffer replacement policy for the message preferences, SPF, therefore, efficiently delivers messages to the destination by reflecting the degree of selfishness to which nodes cooperatively manage their buffer spaces and how frequently and how recently they meet. Consequently, all nodes can cooperatively drop or keep (forward) and replace the messages in the buffer spaces for the message preferences in SPF. SPF outperforms Epidemic, PRoPHET, and SimBet in terms of delivery ratio, network traffic, buffer space, hop count, and replacement frequency.

COUPON: A Cooperative Framework for Building Sensing Maps in Mobile Opportunistic Networks

Human-carried or vehicle-mounted sensors can be exploited to collect data ubiquitously for building various sensing maps. Most of existing mobile sensing applications consider users reporting and accessing sensing data through the Internet. However, this approach cannot be applied in the scenarios with poor network coverage or expensive network access. Existing data forwarding schemes for mobile opportunistic networks are not sufficient for sensing applications as spatial-temporal correlation among sensory data has not been explored. In order to build sensing maps satisfying specific sensing quality with low delay and energy consumption, we design COUPON, a novel cooperative sensing and data forwarding framework. We first notice that cooperative sensing scheme can eliminate sampling redundancy and hence save energy. Then we design two cooperative forwarding schemes by leveraging data fusion: Epidemic Routing with Fusion (ERF) and Binary Spray-and-Wait with Fusion (BSWF). Different from previous work assuming that all packets are propagated independently, we consider that packets are spatial-temporal correlated in the forwarding process, and derive the dissemination law of correlated packets. Both the theoretic analysis and simulation results show that our cooperative forwarding schemes can achieve better tradeoff between delivery delay and transmission overhead. We also evaluate our proposed framework and schemes with real mobile traces. Extensive simulations demonstrate that the cooperative sensing scheme can reduce the number of samplings by 93 percent compared with the non-cooperative scheme; ERF can reduce the transmission overhead by 78 percent compared with Epidemic Routing (ER); BSWF can increase the delivery ratio by 16 percent, and reduce the delivery delay and transmission overhead by 5 and 32 percent respectively, compared with Binary Spray-and-Wait (BSW).

A cross-layer multi-hop cooperative network architecture for wireless ad hoc networks

In this paper, a novel decentralized cross-layer multi-hop cooperative network architecture is proposed and presented. This cross-layer architecture introduces a new cooperative flooding scheme and two decentralized opportunistic cooperative forwarding mechanisms based on randomized coding, and a Routing Enabled Cooperative Medium Access Control (RECOMAC) protocol that enables cooperative forwarding, while incorporating physical, medium access control (MAC) and routing layers. RECOMAC employs randomized coding to realize cooperative diversity, so that relay selection and actuation mechanisms are alleviated and the MAC costs are reduced. The coded packets are routed in the network via the proposed cooperative forwarding schemes, which opportunistically form cooperative sets within a region, not needing a prior route to be established. Essentially, in the RECOMAC architecture, the routing layer functionality is submerged into the MAC layer to provide seamless cooperative communication, while the messaging overhead to set up routes, select and actuate relays is reduced. We evaluate the performance of RECOMAC in terms of network throughput, delay and MAC and routing overhead, in comparison to the conventional architecture based on the well-known IEEE 802.11 MAC and Ad hoc On Demand Distance Vector (AODV) routing protocols. RECOMAC is shown to provide quite significant improvement by an order of magnitude difference in all investigated performance metrics, under a variety of scenarios, considering different network sizes, static and mobile scenarios and networks with multiple flows.