Proposal of Data Triage Methods for Disaster Information Network System Based on Delay Tolerant Networking

Abstract

After the East Japan Great Earthquake in 2011, a robust network communication has been one of significant subjects for the study of Disaster Information System. Then, DTN (Delay Tolerant Network) has been focused for the effective methods for such inoperable network circumstances. However, when DTN is applied for the local areas, there are some problems such as message delivery rate and latency because there are fewer roads, cars, and pedestrians than in urban areas. Therefore, we propose the Enhanced Media Coordinate System for DTN to the architecture in order to provide the Data Triage, Node Selection based on its Territory, and Dynamic FEC (Forward Error Correction). In this paper, the proposed Data Triage Methods that provide the data priority by the user policy and the application type is especially explained, and the results of the computational simulation by the GIS map of a Japanese coastal town is reported. Then, the results are discussed for the future studies of DTN for Disaster Information Network System in local areas.

Vehicular Delay-Tolerant Networks with Image Recognition-Based Adaptive Array Antenna for Winter Road Surveillance in Local Areas

“…In the system, first of all, the road conditions are estimated by the QEF and temperature sensors on vehicles, and the estimated data are stored in each vehicle. Then, when there are vehicles which can receive transmissions or wireless devices on the utility poles along the roads, the data are communicated to others via DTN routing using the data triage methods [10,11].…”

Disaster Management through Delay Tolerant Networks

“…In [13] the authors proposed Enhanced Media Coordinate system for DTN that realize dynamic control of the parameters by the nodes environment, user policies and network conditions in situation of emergencies. The proposed system architecture has three additional functionalities that are Data triage by user specific policies, selection of nodes by its territories and dynamic FEC by population estimation method.…”

“…Data triage method re shuffles the data stored in the buffer according to the marked importance. Unlike the previous forwarding approaches used by DTN in which the latest data arrives and gets forwarded first and with this the data arrived earlier could have to wait for quite long time [13], which could be very bad for the disaster scenarios in which non important data could be using the scarce network resources and the data important for the relief and recovery operation would be delayed unnecessarily. With the data triage, the proper shuffling of the data before forwarding can ignore the less important data based by the policies of the users and give priority to the important data.…”

Delay Tolerant Networking with Data Triage Method based on Emergent User Policies for Disaster Information Network System

“…The basic typed DTN protocol is called the epidemic model because the spread models of virus can predict it. SIR model [10] is one of the epidemic DTN models that are used for the estimation of data delivery rates or the latency (delivery time). When "S" is set to a susceptible population, "I" is set to an infected population, and "R" is set to a recovered population, the evolution of the epidemic is defined by the following equations:…”

“…Therefore, this paper proposes a novel DTN architecture with the Enhanced Media Coordinate System (EMCS) for DTN to realize dynamic parameters control by the nodes' environments, the network conditions, and the user policies under emergent situations. Besides, the proposed methods mainly consist of three additional functions for DTN such as Data Triage by user policies, Node Selection methods by its territory, and Dynamic FEC (Forward Error Correction) by population estimation method [10]. Especially, this paper newly deals with the efficiency of the previous DTN routings by the comparison with the middle city and the local city in Japanese coastal area by the extended experiments of our proposed Data Triage Method.…”