[dtn] AMA question and DTN Data Mules

["Nordgren, Bryce -FS" <[e-mail]>]

Tangent: on cursory inspection, draft-ietf-dtn-ama-01 seems unnecessarily limited to "network management", since nearly all the concepts seem applicable to management of any distributed application operating across challenged links. The draft would seem to describe the case of an "Autonomous Parameterized Procedure Call" commanding a remote Kubernetes cluster to roll out a new deployment of some app to a local network on the other end of a challenged link--except it seems to be focused on network management.

A conceptual piece that may be missing from AMA is synchronized data, or data that should be eventually consistent across application instances present at multiple nodes, where each serves users local to their own node (to offer better response times or conserve bandwidth). Data such as the collection of "users" of the app (Who Are The Actors? Who Are The Managers? Did Someone Get Fired? Is There A New Guy? Did User A Change Her Password?). It may not be appropriate to specify a particular method to pursue consistency, but defining the syncronized data type and its binding to a set of endpoints may be useful. Also, and I haven't read closely enough to understand if this is a problem...Actors and Managers in terrestrial networks may access the network from different nodes, and user generated content (even if it's just a state change due to their interaction) may be supplied from any node. The draft doesn't actually define permissible management operations on individual DTN nodes, so is there a reason to limit these generic concepts to "network management"?

The meat: during the development of the DTN concept, has there been any thought to the use of "dumb media" to connect isolated network islands?

Use Case: An Incident Management Team (IMT) splits some of its essential functions between an Incident Command Post (ICP), chosen for connectivity reasons; and a Forward Operating Base (FOB), chosen for proximity to the fire/earthquake/disaster. The current communication flows between locations may include paper forms or electronic files shared via flash drives.

Deployment scenario: Two "fixed" DTN nodes are set up, one at each location, running a DTN app like 'DTNbox' to sync one or more directories between the two. They also participate on a local network at each facility (where the FOB does not have internet connectivity) and run a webserver. The webserver allows end users to view or download published data (such as the day's Incident Action Plan or maps), as well as upload admin info, like electronic time cards and COVID screenings.

Writing an app to make a smartphone into a "mobile" node (data mule) seems a conceptually straightforward thing to do. This is because a smartphone is smart, and can act like a DTN node that's doggedly trying to join WiFi and pester whatever "fixed" nodes it finds. However, it requires that users install something on their phone, which is likely forbidden if it's an agency phone.

My question is: Is there a spec or a strategy regarding how to dump bundles which need to be moved between nodes to "dumb" media, like a flash drive or a USB hard drive? Someone then carries the dumb media from place to place, plugging it into the DTN node when they arrive. Seems like an on-media structure would need to be developed so nodes could add what they need to transmit and consume bundles destined for them. And since there's no guarantee that two nodes are running the same DTN implementation, it seems that the structure (and allowable operations on said structure) would need to be standardized. Would this be a "mass storage" convergence layer in your parlance?

Has this come up before, and is it dumb?

Thanks,
Bryce




This electronic message contains information generated by the USDA solely for the intended recipients. Any unauthorized interception of this message or the use or disclosure of the information it contains may violate the law and subject the violator to civil or criminal penalties. If you believe you have received this message in error, please notify the sender and delete the email immediately.