1. DTN Network Management Scenarios and General Requirements Will Ivancic william.d.ivancic@nasa.gov 216-433-3494

2. DTN D is for Delay (Deep Space) D is for Disruption (Military) D is for Disconnected (All)

3. 3 DTN in a nutshell DTN Source DTN Bundle Forwarding Agent DTN Destination Where are you headed? Knoxville, Wheeling, then Fort Pitt. Can you take this letter to my Brother at Fort Pitt? Yes Mam, I sure can. Dave Smith @ Ft. Pitt Dave Smith @ Ft. Pitt Dave Smith @ Ft. Pitt Dave Smith @ Ft. Pitt

4. 4 DTN in a nutshell DTN Bundle Forwarding Agent Dave Smith @ Ft. Pitt Dave Smith @ Ft. Pitt DTN Bundle Forwarding Agent DTN Destination

5. 5 Why DTN? Cons Non-Optimal Solution for particular situations such as if limited infrastructure exists Adds Overhead Can be significant overhead depending on the packet size Pros Flexibility Reliability Robustness DTN is a network overlay abstraction. This requires overhead. One is either willing to trade overhead for flexibility or they are not.

6. 6 Delay/Disruption Tolerant Network (DTN) A standardized store and forward protocol and routing protocol Designed for extreme environments Large transmission link delays Extended periods of network partitioning Routing capable of operating efficiently in the following environments Frequently-disconnected Pre-scheduled Opportunistic link availability High per-link error rates making end-to-end reliability difficult Heterogeneous underlying network technologies (including non- IP-based internets) The architecture operates as an overlay network Institutes a new naming architecture based on Uniform Resource Identifier (URI) Concept of Late Binding of Name to Address

7. 7 DTN Environments Scheduled (long delay) Opportunistic (Intermittent Connectivity, Short Delay)

8. 8 Known problems with DTN bundling IRTF DTN Research Group adopted bundling as ‘universal’ way to deal with DTNs. Currently not investigating alternatives. Bundling is not mature by any stretch of the imagination Security, routing, naming, reactive fragmentation, key and policy management, etc. are still open issues. Network overlays inherit all the good and bad of the underlying networks. Example, if one does not have a good handle of how to secure an ad hoc network, running DTN over an ad hoc network implies one has to address both the ad hoc and the DTN issues (routing, quality of service, security, etc...) The current bundle design has no built-in reliability checks. Security protocols are emphasized. Reliability is currently (as of November 2008) being retrofitted as an add-on to security. [Fixable] The current bundling protocol (RFC 5050) assumes all nodes know current UTC thus requiring network synchronization. [Fixable] Bundling is really still a research effort!

9. 9 Palm Island Resort, Dubai, 14 Dec 2003 (UK-DMC) www.dmcii.com The Cape of Good Hope and False Bay. False colours – red is vegetation. Taken by UK-DMC satellite on the morning of Wednesday, 27 August 2008. Downloaded using bundling over Saratoga, with proactive fragmentation. Fragments assembled at NASA Glenn, then post processed at SSTL. First sensor imagery delivered by bundles from space.

10. 10 Home Agent VMOC Open Internet VMOC Database Satellite Scheduler & Controller Ground Station 3 Ground Station 2 Ground Station 1 ->> Time ->> Large File Transfer Over Multiple Ground Stations - DTN is a Potential Solution - DTN Bundle Agent Intermediary DTN Bundle Agent Intermediary DTN Bundle Agent Intermediary DTN Bundle Agent Sink

11. Scenarios Deep Space Mars Relay Simple Sensor Networks Data Mule Rapid Disruption (Fades due to RF) Low Earth Orbiting Sensor Satellite Geostationary Bent Pipe Relay Satellite Unmanned Aeronautical Vehicles

12. Mars Relay Long Delay Short Delay DTN Bundle Agent

13. UAV via GEO Satellite DTN Bundle Agent DTN Bundle Agent DTN Bundle Agent RF Relay DTN Bundle Agent

14. Data Mule

15. Low Earth Orbiting Satellite

16. Network Management Monitoring and Measurement Debugging and Troubleshooting Performance profiles -- delay and throughput; disruption and connectivity Configuration Routing Security configurations (and policy) DTN-Tables ? (long term)  Applications (related to traffic generation for testing and monitoring purposes) General User Applications that can be use to test, stress and exercise the network (i.e. DTNtraceroute, DTNsend/receive, DTNperf, etc...) DTN useful applications (i.e DTNdatabase synchronization (DTNrsync), DTNmail, DTNchat ?, etc...)

17. Network Management Monitoring and Configuration General Requirements Local Network Management Remote Network Management Monitoring Bundle Processing System Characteristics Convergence Layers Multi-Homing Radios Processing Power Onboard Storage Configuration Routing Name Resolution Local and Network Time Security

18. Definitions Local Management ≡ Logged into the device locally or via Real-time access such as via a connected IP network Assume high bandwidth, no disruption and insignificant delay Remote Management ≡ Managed over a DTN network Handles Long Delays, Long Periods of Disruption, and Low Bandwidths

19. General Requirements Management and Configuration should work for all DTN environments High delay, long periods of disconnection, low bandwidth System may be multiple hops away and never reachable in a single hop System may not be synchronized (although current bundling RFC 5050 assumes synchronization) Multiple security levels Secure Login and encrypted data transfer (i.e. SSH or TLS for local management, something yet to be defined for remote management) Monitoring - Modest Security Configuration - High Security Remote Management uses bundling Remote Configuration Incremental Test, Validation, restore/recovery

20. Utilities – beginnings of NetMgt (Make utilities interoperable between ION and DTN-2) DTN-ping DTN-send/receive DTN-traceroute DTN-perf DTN-heartbeat DTN-email DTN-chat Bundle Count / Traffic Measurement (NEW Request)

21. NASA DEN Phase-0 Scenario Phase-0 Continuous Connectivity Static routing No BP Security Delay: Lunar 3 sec BW: 128kbps [>100Mbps] BP/LTP/Encap or BP/LTP/IP/Encap Delay: 100s msec? BW: 72/k/192k Story EVA sending some sort of telemetry (different kinds to APL and JPL) Understand that EVA data wouldn’t really go to APL/JPL BP/LTP/Encap or BP/LTP/IP/Encap? OhioU has TCPCL for ION? BW: 10Mbps Limit the amount of available storage (later)

22. DTNBone We invite you to participate in the DTNbone Web Page http://www.dtnrg.org/wiki/DtnBonehttp://www.dtnrg.org/wiki/DtnBone Mail list http://korgano.eecs.ohiou.edu/mailman/listinfo/dtnbonehttp://korgano.eecs.ohiou.edu/mailman/listinfo/dtnbone Establish a worldwide collection of nodes running DTN bundle agents and applications. Remote management and control of nodes, Interoperability, Application deployment and testing, Operations across administrative boundaries.

23. DTN GW Rover Habitat Science Sensor 1 Mbps 256 kbps 128 kbps EARTH MOON L2 Relay Lunar Relay Always ON ? Intermittent Multiple Switched Ground Stations emulated as one single DTN GW International Partner #2 International Partner #1 Switched

24. DTN GW L2 Relay Habitat Lunar Relay Rover Sensor SW CS Real-time Control Plan Defined as part of Local Management CS Channel Simulator (Rate, BER and Connectivity) DTN Data Flow