Relay Gateway Research Articles

Toward Quantifying Decentralization of Blockchain Networks With Relay Nodes

In this paper, we present a methodology for quantifying the decentralization degree of a blockchain network. To accomplish this, we use two well-known graph models of Erdös-Rény and Barabási–Albert in order to study the blockchain network topology. We then quantify the decentralization degree using the clustering coefficient of our network models. We validate our approach through extensive simulations and analyze the decentralization degree with respect to network parameters such as the number of connections per node and the peer selection algorithm. Our results expose the trade-off between the average shortest path and the decentralization degree. Furthermore, we observe the impact of the average shortest path on the network speed and traffic overhead. Finally, we demonstrate that the presence of hub-like nodes such as relay gateways negatively impacts the decentralization degree of blockchain networks.

Design and Implementation of the Relay Gateway Driver Software Based on AudioCode Chip

In order to solve the problem of the PSTN network and IP network interconnection, in the study of digital relay server-driven software system architecture based on low-level driver software point of departure from the digital relay server, the proposed media and letter between the two networksso that the signaling conversion server communicate with each other, in order to achieve the signaling protocol conversion between the two networks; design of a digital relay server to complete media conversion between the two networks, the interconnection between two networks.

Facilitating Remote Laboratory Deployments Using a Relay Gateway Server Architecture

Hands-on experiments prepare students to deal with real-world problems and help to efficiently digest theoretical concepts and relate those to practical tasks. However, shortage of equipment, high costs, and the lack of human resources for laboratory maintenance and assistance decrease the implementation capacity of the hands-on training laboratories. At the same time, the Internet has become a common networking medium and is increasingly used to enhance education and training. In addition, experimental equipment at many sites is typically underutilized. Thus, remote laboratories accessible through the Internet can resolve cost and access constraints as they can be used at flexible times and from various locations. While many solutions have been proposed so far, this paper addresses an important issue of facilitating remote lab deployments by providing remote connectivity services to lab providers using a Relay Gateway Server architecture. A proof-of-concept solution is described which also includes other previously reported useful features. The system has been tested in engineering labs and student assessment is provided.

IPv6 based relay gateway protocol in hybrid networks

During the past few years, WMAN (Wireless Metropolitan Area Network) and WLAN (Wireless Local Area Network) provided fast, convenient and reliable solution for all kinds of users. With the development of the communication technology, the future wireless networks will allow mobile users access Internet anywhere, anytime. Therefore, it is a natural trend to combine different wireless networks to provide a seamless roaming for users. It is feasible for mobile terminal which have multiple modes to handoff between different networks. A relay gateway protocol for the WLAN-mode nodes (mono-mode WLAN nodes and dual-mode nodes) in the hybrid network of IEEE 802.16 WMANs and IEEE 802.11 WLANs is proposed to provide wider mobility. Dual-mode mobile nodes with good service can provide WLAN links to nearby WLAN-mode nodes with bad service or out of the WLAN coverage. Simulation results show that the relay gateway scheme can improve network performance of the hybrid networks. Moreover, the relay gateway method can bring additional service coverage and increase the capacity of WMANs and WLANs.

Fast Retransmission for Concurrent Multipath Transfer (CMT) over Vehicular Networks

In vehicular networks, a vehicle can connect to a nearby Rode Side Unit (RSU) covered by a relay gateway using IEEE 802.11p. When a vehicle communicates with a server, the link between the vehicle and RSU is a wireless link, while the link between the gateway and the server is a wired link. In most cases, packets are lost in the wireless link, not in the wired link. In this paper, we propose fast retransmission made by the Relay Gateway for Concurrent Multipath Transfer (RG-CMT) in vehicular networks. When packets are lost due to error loss or handoff loss in the wireless link, RG-CMT is able to fast retransmit lost packets from the relay gateway to the vehicle. Comparing to fast retransmission made by the server, retransmission made by the relay gateway saves transmission time and bandwidth. The simulation results show that RG-CMT can recover from handoff faster than CMT, and improve the throughput of CMT by 41% when the packet loss rate over the IEEE 802.11p link is 10%.

Connecting IPvX Networks Over IPvY with a P2P Method

During the transition from IPv4 to IPv6, the IPv6 islands inside the IPv4 networks need to communicate with each other and with the native IPv6 network. The drawback of existing IPv6 transition methods is that relay gateways become potential communication bottlenecks. In this paper, a new method--PS64--is presented to connect IPv6 islands together over IPv4 network and reduce the reliance on these relays by shifting the burden to edge gateways on each island. In this method, direct tunnels are set up between the IPv6 islands, and a P2P network is maintained between edge gateways of these islands to propagate information of tunnel end points. After describing the algorithm, we analyze the connectivity of the P2P network, the scalability of this algorithm, and present the prototype and experiments. The results of our analysis and experiments show that the proposed method is reliable, scalable and effective. Obviously, this technique works for all IPvX over IPvY situations.

Data relaying with constraints in hierarchical sensor networks

In this paper we present and discuss several optimisation problems that arise in the management of data flow in wireless sensor networks (WSNets). We consider a hierarchical architecture for WSNets composed of sensors, relays, and relay gateways. Sensors send data they generate at a known average bit rate to relays in one hop. The relay nodes use a multi-hop mechanism to reach a set of assigned gateways which then forward the data directly to the base station. We are concerned with finding an assignment of relay gateways to relays so that certain constraints are satisfied. We define a unified model in which constraints such as lifetime, data delay, and data flow splitting are formulated in terms of four optimisation problem in graphs.

AHBP: An efficient broadcast protocol for mobile Ad hoc networks

Broadcast is an important operation in many network protocols. It is utilized to discover routes to unknown nodes in mobile ad hoc networks (MANETs) and is the key factor in scaling on-demand routing protocols to large networks. This paper presents the Ad Hoc Broadcast Protocol (AHBP) and its performance is discussed. In the protocol, messages are only rebroadcast by broadcast relay gateways that constitute a connected dominating set of the network. AHBP can efficiently reduce the redundant messages which make flooding-like protocols perform badly in large dense networks. Simulations are conducted to determine the performance characteristics of the protocol. The simulation results have shown excellent reduction of broadcast redundancy with AHBP. It also contributes to a reduced level of broadcast collision and congestion.