Notes from IETF Delay Tolerant Networking Workshop, Minneapolis.
9 March 2005, 1530-1730.
These notes are paraphrased speakers comments that are not captured in slides, and an attempt at logging audience questions and remarks.
Kevin Fall Opening remarks.
[Vint Cerf] Its very important that you set aside your intuitions when thinking about DTN. Internet approaches dont always apply.
Bob Durst DTNRG: Where are we?
There are situations where you cannot or should not run IP.
There is pressure to support streaming applications.
Architecture currently uses expiration time instead of hop count. This idea needs refinement.
We are struggling with the meaning of regions.
Needs refinement: How to know when to trust lower layers?
DHCP-like issues and bootstrapping is an open problem.
Keith Scott Bundle Protocol Specification
There have been two revisions of the Bundling Specification. Here are some things needed for the next revision of the draft.
The dictionary appears to be a good idea. It is like a string table. It needs refinement.
Header is not necessarily word aligned. This needs to be refined or reconsidered.
We need to consider extensible headers.
Avri Doria SNC update and PROPHET protocol (no slides)
Avri is encountering and examining many of the same issues as DTN, like addressing and movement of nodes through regions.
Manikantan Ramadas LTP Update
LTP is the Licklider Transmission Protocol. It can also be thought of as the Long-Haul Transport Protocol
[Kevin Fall] What do the extension documents cover? Answer: Security.
[Vint Cerf] What are the assumptions in transmission systems that use LTP? Answer: Data streams in one direction, ACKs in the other.
Stephen Farrel SeNDT
Noise/Quiet application is monitoring of ambient noise for various purposes, e.g. environmental noise pollution.
[Vint Cerf] Can you put this on automobiles? Answer: An audience member responds that he is looking into this.
Michael Demmers DTN Reference Implementation
[Keith Scott] Simulation results take into account all headers.
[Vint Cerf] Some of these results can be explained by packetization effects.
Simulation Note: There is no flow control in the system. The Sendmail results are a result of Sendmail not being aggressive it is not a protocol failure.
SFTP is not Secure FTP. It is Simple FTP, a Tcl application that mimics FTP.
[Audience] Any plans on incorporating LTP into the Reference Implementation? Answer: Yes, it is on the To-Do list.
Susan Symington DTN Security
Bundle Daemon can deny access to network. It is the first level of access control.
[Vint Cerf] There is a clash between replay protection and bundle duplication. This is an issue.
[Kevin Fall] Routing loops are sometimes the optimal solution to routing problems.
Protecting against Replays will need more state at each node.
Protection against Replay and Denial of Service attacks is a hard problem.
[Vint Cerf] Peripheral security makes me nervous. Notion of boundaries in radio environments is squishy. How much can we depend on defining a boundary?
[Kevin Fall] Routing agents might intervene.
[Carsten Bormann] How useful is it to protect headers if I want to attack/misuse the system? I can misuse system infrastructure if I have cohorts and collaborators in the network.
[Michael Demmers] Reactive fragmentation might not be an untenable option.
[Avri Doria] Theres also the key-distribution problem.
[Sandra Murphy] Concerned with Byzantine compromise, e.g. compromise of routers.
[Vint Cerf] Software integrity of the bundle router is a big problem. Also, network management is a big hole that needs work.
[Terry Davis(?) (Boeing)] DTN seems relevant to A380/A787 aircraft connection system.
Kevin Fall Presentation of Oceanographic applications of DTN.
It is important to note that these slides were not made by me (Kevin Fall). It shows that people understand the ideas of DTN and how/where it applies.
Kevin Fall Concluding Remarks.
When should meet again? Every other IETF? (Audience seems to agree.)
[Avri Doria] DTN is relevant to ICT for Peace, to alert the world of events like war breaking out, emergencies, etc.
[Vint Cerf] DTN is also useful as a means to provide emergency communications.