Gen Motoyoshi

Proposal and evaluation of a future mobile network management mechanism with attractor selection

Several task forces are currently working on how to design the future Internet and it is high time for research work to also move a step forward to future mobile networks on a large scale. In this article, we propose a future mobile network management method based on a combination of OpenFlow and the biologically inspired attractor selection method to achieve scalability and energy efficiency. In other words, we propose novel approaches to wireless network management by extending the attractor selection mechanism in path and cluster management for signaling cost reduction. First, in path management, we establish a control method that each mobile node selects the best suited interfaces in accordance with instantaneous live traffic volume. Then, in cluster management, we design a network management method that network devices select the best OpenFlow cluster to join in order to reduce handover signaling cost. Through autonomous decisions of each mobile node and network device, the whole wireless network can be managed in an autonomous, energy efficient, and robust manner.

Future mobile network management with attractor selection

Several task forces have been working on how to design the future Internet and it is high time for research work to move a step forward to networks on a large scale. In this paper, we propose a future mobile network architecture on a combination of OpenFlow and the attractor selection method to achieve scalability and energy conservation. In addition, we propose novel approaches to wireless network management by extending the attractor selection mechanism in route calculation and signaling cost for energy conservation. First, each mobile node selects the best suited interfaces in accordance with instantaneous live traffic volume. Then, network devices select the best cluster to join to reduce handover signaling cost. Through autonomous decision of each mobile node and network device, the whole wireless network can be managed in an energy efficient and robust manner.

Quality of service of mobile users for longcut routes with congested access points

Network resources for mobile users such as available bandwidth fluctuate depending on the level of background traffic. The deployment of many access points enables mobile users to access more network resources on their way to their destination by taking the longcut route rather than the shortcut route. These users pay some extra cost to take the longcut but obtain greater gains, such as in throughput, over the shortcut route. Previous research has shown that the gain-to-cost ratio can be more than double for the longcut route. No considerations, however, have been made for the case in which resource fluctuation is due to network congestion. This paper investigates the Quality of Service (QoS) for a longcut route with fewer resources (real resources) compared with that for one with the total resources (ideal resources) in the longcut route calculation. The results show that, on average, users have gains of approximately twice in real resources of their gains in ideal resources. This finding indicates that users can greatly improve their gains if they could accurately predict the resource fluctuation.

Function-distributed mobility system for the future Internet

Recently societal requirements have become so complicated that the current Internet is facing many challenging issues to overcome. Several task forces have been working on research on the future Internet in a clean slate manner and mobility management is one of the key issues to be considered. Mobility management in the future Internet is still designed in an “all-in-one” way where all management functions are tightly kept at a single location and this results in cost inefficiency and can be an obstruction to constructing flexible systems. In this paper, we propose a function-distributed mobility management system that can enable more flexible future Internet construction. Furthermore, we show the effectiveness of our proposed system via the cost analysis with a random walk mobility model.

A Wi-Fi P2P communication platform between wireless LAN memory cards: Prototype implementation and performance evaluation

Wi-Fi Peer to Peer (P2P), commercially known as Wi-Fi Direct, is a recent industry standard that allows user devices to communicate with each other without requiring a Wi-Fi access point or Internet connectivity. Offering promising solutions for secure and high-throughput device to device communication over moderately high range, Wi-Fi P2P can potentially revolutionize M2M communication and Internet of Things (IoT) towards an all-connected wireless ecosystem. Secure Digital (SD) memory cards with built-in processing unit and Wireless LAN chipset can serve as a small standalone communication terminal which on installation of a communication protocol stack and a data-sharing application may enable connection establishment and data communication between memory cards. Such architecture may find interesting applications with manifold advantages for device-to-device data sharing in public gatherings without requiring cellular network or WLAN access points. In this paper, we develop an architecture to establish Wi-Fi P2P connection between SD memory cards and enable automatic data sharing by proximity-based device-to-device communication between mobile user equipments. The prototype does not use any of the resources of host device barring power. The key contribution of this paper is the development of a standalone prototype of our proposition on off-the-shelf WLAN SD memory cards and its experimental performance evaluation.

MTFR: Mobility Tolerant Firework Routing

In this paper, we propose a novel mobility assisted, adaptive broadcast routing mechanism called Mobility Tolerant Firework Routing (MTFR) that improves node reach ability especially in situations with high mobility. We evaluate our proposal by simulations with the random walk and random waypoint mobility models and disclose tendencies that can be observed with regard to typical parameters for wireless communication. As a result, we show that our proposed method produces better reach ability in many aspects at the expense of a small additional transmission delay and intermittent traffic overhead, as well as some specific no recoverable conditions are revealed due to wireless coverage density. Hence, an extension with adaptive parameter management has the potential to produce even better reachability and we thus consider MTFR to be a promising routing protocol, feasible enough for future Internet infrastructures.

Route instruction mechanisms with ‘longcut’ paths for mobile users

The recent advent of smartphones and mobile thin-clients has increased opportunities for people to download a large volume of data via wireless access networks while they on the move. In this study, we considered a scenario in which a mobile user moving from one location to another has to arrive at the destination within a certain period of time and wants to obtain as much data as possible before arriving there. In scenario like this, wireless access points on routes that a lot of people pass through become congested. In particular, if the communication range of the wireless access point is limited like wireless local access networks, the wireless bandwidth becomes more competitive. We therefore propose route instruction mechanisms for mobile users that consider ‘longcut’ paths. Our mechanisms direct mobile users to another route on which wireless access points are less competitive. However, we need to consider the tradeoff between the loss caused by the additional movement and the amount of additionally downloaded data. Furthermore, when there are two or more users, this route instruction problem can be modeled as a cooperation problem because the users selfishly try to occupy the best route for themselves. We therefore came up with and compared cooperative and non-cooperative route instruction mechanisms. Computer simulation demonstrated that the former approach brings better fairness for users.

Throughput improvement by disruption-suppressed channel switching in multi-channel ad-hoc networks

As Internet of Things (IoT) and smart devices are becoming widespread, expectations for large-scale ad-hoc networks are increasing. To accommodate a large number of nodes, ad-hoc networks should use multiple channels. Thus, dynamic channel switching methods in multi-channel ad-hoc networks have been investigated to control congestion of the channel. However, such channel switching has a considerable impact on the routing layer. Channel switching causes link failure, and routing protocols are forced to recalculate the route related to channel switching nodes. As a result, end-to-end communications may be disrupted during route recalculations. In this paper, we propose a channel-switching scheme which mitigates channel congestion for throughput improvement while suppressing the end-to-end communication disruption. The proposed scheme properly classifies nodes according to whether they are allowed to switch channels on the basis of the current route by which nodes with multiple radio interfaces are connected. Selecting nodes to switch their channel for mitigating congestion can suppress the communication disruption. Our simulation results showed that our proposed scheme achieved 1.8 times throughput by mitigating congestion compared with the initial state at which nodes randomly select the channel. It was also similar throughput to a centralized scheme which dedicate to mitigate congestion. Besides, proposed scheme produced half the number of communication disruptions owing to the proper selection of nodes.