A DTN Gateway-Based Architecture for Web Access in Space Internet

Abstract

A Delay/Disruption-Tolerant Network (DTN) has received more attention as an expected solution in situations where it is difficult to provide a stable and continuous Internet connection. The purpose of this research is to design a client–server model for space Internet in order to have access to the web documents hosted by an interplanetary node. One of the DTN implementations named Interplanetary Overlay Network (ION) is introduced to provide the main functions to allow networked communications in deep space. In this paper, we propose an architecture for web document access in space Internet over DTN. Our web architecture is based on the DTN Gateway between terrestrial and space Internet that acts as a web proxy and bundle forwarder according to the type of web documents; it works as a web proxy for static web documents, while it works as bundle forwarder between DTN client and DTN server for other web documents. The HyperText Transfer Protocol (HTTP) requests and responses are formatted onto bundles by using bpsendfile and bprecvfile, and the DTN Gateway forwards them as a contact basis in space Internet. We have reported the evaluation results from our implementation by measuring the bit error rate and delay according to the size of static web documents.