Assessing and improving an approach to delay-tolerant networking

Delay-tolerant networking (DTN) is a term invented to describe and encompass all types of long-delay, disconnected, disrupted or intermittently-connected networks, where mobility and outages or scheduled contacts may be experienced. 'DTN' is also used to refer to the Bundle Protocol, which has been proposed as the one unifying solution for disparate DTN networking scenarios, after originally being designed solely for use in deep space for the 'Interplanetary Internet.' We evaluated the Bundle Protocol by testing it in space and on the ground. We have found architectural weaknesses in the Bundle Protocol that may prevent engineering deployment of this protocol in realistic delay-tolerant networking scenarios, and have proposed approaches to address these weaknesses.Comment: 2 pages; First Annual CCSR Research Symposium (CRS 2011), Centre for Communication Systems Research, 30 June 201

Security Analysis of DTN Architecture and Bundle Protocol Specification for Space-Based Networks

A Delay-Tolerant Network (DTN) Architecture (Request for Comment, RFC-4838) and Bundle Protocol Specification, RFC-5050, have been proposed for space and terrestrial networks. Additional security specifications have been provided via the Bundle Security Specification (currently a work in progress as an Internet Research Task Force internet-draft) and, for link-layer protocols applicable to Space networks, the Licklider Transport Protocol Security Extensions. This document provides a security analysis of the current DTN RFCs and proposed security related internet drafts with a focus on space-based communication networks, which is a rather restricted subset of DTN networks. Note, the original focus and motivation of DTN work was for the Interplanetary Internet . This document does not address general store-and-forward network overlays, just the current work being done by the Internet Research Task Force (IRTF) and the Consultative Committee for Space Data Systems (CCSDS) Space Internetworking Services Area (SIS) - DTN working group under the DTN and Bundle umbrellas. However, much of the analysis is relevant to general store-and-forward overlays

A Performance Evaluation of NACK-Oriented Protocols as the Foundation of Reliable Delay- Tolerant Networking Convergence Layers

Delay-Tolerant Networking (DTN) is an active area of research in the space communications community. DTN uses a standard layered approach with the Bundle Protocol operating on top of transport layer protocols known as convergence layers that actually transmit the data between nodes. Several different common transport layer protocols have been implemented as convergence layers in DTN implementations including User Datagram Protocol (UDP), Transmission Control Protocol (TCP), and Licklider Transmission Protocol (LTP). The purpose of this paper is to evaluate several stand-alone implementations of negative-acknowledgment based transport layer protocols to determine how they perform in a variety of different link conditions. The transport protocols chosen for this evaluation include Consultative Committee for Space Data Systems (CCSDS) File Delivery Protocol (CFDP), Licklider Transmission Protocol (LTP), NACK-Oriented Reliable Multicast (NORM), and Saratoga. The test parameters that the protocols were subjected to are characteristic of common communications links ranging from terrestrial to cis-lunar and apply different levels of delay, line rate, and error

Delay/Disruption Tolerant Networking for the International Space Station (ISS)

Disruption Tolerant Networking (DTN) is an emerging data networking technology designed to abstract the hardware communication layer from the spacecraft/payload computing resources. DTN is specifically designed to operate in environments where link delays and disruptions are common (e.g., space-based networks). The National Aeronautics and Space Administration (NASA) has demonstrated DTN on several missions, such as the Deep Impact Networking (DINET) experiment, the Earth Observing Mission 1 (EO-1) and the Lunar Laser Communication Demonstration (LLCD). To further the maturation of DTN, NASA is implementing DTN protocols on the International Space Station (ISS). This paper explains the architecture of the ISS DTN network, the operational support for the system, the results from integrated ground testing, and the future work for DTN expansion

Networked Operations of Hybrid Radio Optical Communications Satellites

In order to address the increasing communications needs of modern equipment in space, and to address the increasing number of objects in space, NASA is demonstrating the potential capability of optical communications for both deep space and near-Earth applications. The Integrated Radio Optical Communications (iROC) is a hybrid communications system that capitalizes on the best of both the optical and RF domains while using each technology to compensate for the other's shortcomings. Specifically, the data rates of the optical links can be higher than their RF counterparts, whereas the RF links have greater link availability. The focus of this paper is twofold: to consider the operations of one or more iROC nodes from a networking point of view, and to suggest specific areas of research to further the field. We consider the utility of Disruption Tolerant Networking (DTN) and the Virtual Mission Operation Center (VMOC) model

On Applications of Disruption Tolerant Networking to Optical Networking in Space

The integration of optical communication links into space networks via Disruption Tolerant Networking (DTN) is a largely unexplored area of research. Building on successful foundational work accomplished at JPL, we discuss a multi-hop multi-path network featuring optical links. The experimental test bed is constructed at the NASA Glenn Research Center featuring multiple Ethernet-to-fiber converters coupled with free space optical (FSO) communication channels. The test bed architecture models communication paths from deployed Mars assets to the deep space network (DSN) and finally to the mission operations center (MOC). Reliable versus unreliable communication methods are investigated and discussed; including reliable transport protocols, custody transfer, and fragmentation. Potential commercial applications may include an optical communications infrastructure deployment to support developing nations and remote areas, which are unburdened with supporting an existing heritage means of telecommunications. Narrow laser beam widths and control of polarization states offer inherent physical layer security benefits with optical communications over RF solutions. This paper explores whether or not DTN is appropriate for space-based optical networks, optimal payload sizes, reliability, and a discussion on security

A Roadmap Toward a Unified Space Communication Architecture

In recent years, the number of space exploration missions has multiplied. Such an increase raises the question of effective communication between the multitude of human-made objects spread across our solar system. An efficient and scalable communication architecture presents multiple challenges, including the distance between planetary entities, their motion and potential obstruction, the limited available payload on satellites, and the high mission cost. This paper brings together recent relevant specifications, standards, mission demonstrations, and the most recent proposals to develop a unified architecture for deep-space internetworked communication. After characterizing the transmission medium and its unique challenges, we explore the available communication technologies and frameworks to establish a reliable communication architecture across the solar system. We then draw an evolutive roadmap for establishing a scalable communication architecture. This roadmap builds upon the mission-centric communication architectures in the upcoming years towards a fully interconnected network or InterPlanetary Internet (IPN). We finally discuss the tools available to develop such an architecture in the short, medium, and long terms. The resulting architecture cross-supports space agencies on the solar system-scale while significantly decreasing space communication costs. Through this analysis, we derive the critical research questions remaining for creating the IPN regarding the considerable challenges of space communication.Peer reviewe

Tests Scenario on DTN for IOT III Urbanet collaboration

This document presents the first part of the DTN (Delay Tolerant Network) study within IOT (Internet Of Things) context. The motivation for using generic protocols able to handle the constraints due to the IOT is highlighted with the choice of Bundle Protocol. A study of existing implementations of this protocol is realised within a sensor context. We justify the choices made for our implementation, then we define the mechanisms which we will test with the IOT-Lab platform by following the protocol of tests we have developed. The performance analysis are also presented

Implementing Delay-Tolerant Networking at Morehead State University

A thesis presented to the faculty of the College of Science at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Nathaniel J. Richard on April 28, 2017

Expériences et résultats pour les DTN pour l’IOT Collaboration III Urbanet

This document presents the full study of the DTN (Delay Tolerant Network) within IOT (Internet Of Things) context. The motivation for using generic protocols able to handle the constraints due to the IOT is highlighted with the choice of the Bundle Protocol. A study of existing implementations of this protocol is realised within a sensor context. We justify the choices made for our implementation, then we define the mechanisms which we test with the Cooja platform by following the protocol of tests we have developed. The results of the experiments are analysed.Ce document présente l’étude complète des DTN (Delay Tolerant Network) dans un contexte d’IOT (Internet Of Things). La motivation de l’utilisation de protocoles génériques capables de supporter les contraintes inhérentes au contexte IOT est mise en avant avec le choix du Bundle Protocol. Une étude des implantations existantes de ce protocole est faite dans un contexte capteur. Nous proposons notre implantation en justifiant les choix réalisés, puis nous définissons des mécanismes que nous testons avec la plate-forme Cooja en suivant le protocole de tests que nous avons élaboré. Les resultats de ces expérimentations sont analysées