HBSD: An External Router For DTN2

· Overview · Global Architecture and Source Code · Implementation · Related Dependencies · Related Publications · Related Talks · People Involved · Contact

Design and Development of HBSD (our optimal joint scheduling and drop policy for DTN) as an External Router for DTN2 Overview As described in the papers presented in the related publications section below, HBSD (History Based Scheduling and Drop) is an efficient joint scheduling and drop policy that can optimize different performance metrics in a DTN, like average delay and delivery probability. We have implemented HBSD for DTN2. DTN2 is the current reference implementation (in C++) for Delay Tolerant Networks by the DTN Research Group. It acts as an additional networking layer between the application layer and the transport layer. DTN2 encapsulates application data into bundles, thus it is often called the "bundle layer", and calls on the transport layer to forward bundles from one node to the next. When two nodes are within range and have an established connection on the transport layer, the "link" between them is considered "open". While the transport layer, using traditional networking protocols, ensures delivery of bundle data from one node to the next, DTN2 is meant to ensure end-to-end delivery of bundles across the entire network. The decision making aspect of the bundle layer, which controls what bundles are sent over what links, is called the router. DTN2 includes a number of internal routers, such as: Static: only sends a bundle over an open link whose remote endpoint is the bundle's final destination Flood: sends every bundle across every link as soon as it is open PRoPHET. DTN2 includes also support for external routers such as RAPID (developed in Java) and our HBSD external router (developed in C++). Global Architecture & Source Code As described in the Figure 1, the HBSD external router run as separate processes and communicates with DTN2 by sending and receiving XML messages over a multicast socket. DTN2 sends XML event messages to a multicast socket, from which the HBSD external router reads. HBSD external router then processes the message, and may or may not decide to send back an XML request message, prompting DTN2 to take action. Figure 1: HBSD External Router + DTN2 · Download HBSD source code. · Learn more About HBSD external router mains building blocks. · Learn more about the different steps to follow in order to install both DTN2 and HBSD and run them correctly. · Learn more about the DTN2 and HBSD external router configuration. Our HBSD external router was tested on the SCORPION testbed at University of California Santa Cruz. Figure 2 depicts some of the mobile testbed nodes. Figure 2: SCORPION testbed mobile nodes Related Dependencies · The DTN2 source code: it embodies the components of the DTN architecture, while also providing a robust and flexible software framework for experimentation, extension, and real-world deployment. · Berkeley DB: The Berkeley DB package contains programs and utilities used by DTN2 and HBSD for database related functions. (A DB database is used as persistent storage for Bundles) · Xerces-C++: a validating XML parser written in a portable subset of C++. Xerces-C++ makes it easy for both HBSD and DTN2 to read and write XML data. · Oasys (Object-oriented Adaptors to SYStem interfaces): a C++ library that provides a set of wrapper classes and utilities for systems programming projects. Related Publications · Amir Krifa, Chadi Barakat, Thrasyvoulos Spyropoulos, "Optimal Buffer Management Policy for Delay Tolerant Networks", in proceedings of the 5th IEEE Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON 2008), San Francisco, June 2008.(CA), June 2008. ---- BEST PAPER AWARD · Amir Krifa, Chadi Barakat, Thrasyvoulos Spyropoulos, "An Optimal Joint Scheduling and Drop Policy for Delay Tolerant Networks”, in proceedings of the WoWMoM Workshop on Autonomic and Opportunistic Communications, Newport Beach (CA), June 2008. Related Talks · Chadi Barakat, Presentation of the paper "Optimal Buffer Management Policy for Delay Tolerant Networks", University of California Santa Cruz (UCSC), Santa Cruz, USA, 2010. · Amir Krifa, Presentation of the paper “Optimal Joint Scheduling and Drop Policy for DTN”, ENSI, Tunisia, 2008. · Amir Krifa, Presentation of the paper “Optimal Joint Scheduling and Drop Policy for DTN”, WoWMoM conference, Newport Beach (CA), USA, 2008. · Thrasyvoulos Spyropoulos, Presentation of the paper "Optimal Buffer Management Policy for Delay Tolerant Networks", IEEE Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON 2008), San Francisco, June 2008.(CA), USA, 2008 People involved Amir Krifa Chadi BARAKAT Thrasyvoulos Spyropoulos Contact Please send any general or development related question about BitHoc to Amir.Krifa@sophia.inria.fr