Delay/Disruption Tolerant Networking (DTN) Working Group

Meeting: IETF 123 - Madrid
Session: Thursday III (120 minutes)
Date/Time (UTC): 24 JULY 2025 / 12:30 - 14:30

Area: INT
Area Director: Erik Kline
Chairs: Ed Birrane, Rick Taylor
Secretary: Adam Wiethuechter

Introduction, Note Well, Milestones (05 mins)

Speaker(s): Chairs
Document(s): N/A

• Birrane: 2 RFCs recently published, 11 drafts adopted, 7 related; AD
  to speak at beginning
• Kline: invited people to volunteer to serve as ADs

CoAP over BP (05 mins)

Speaker(s): Carles Gomez
Document(s): draft-gomez-core-coap-bp-04

• Gomez: draft being adopted in CoRE WG
• Kline: expand resolvability of .ipn.arpa in DNS?
• chairs: please don't hold up draft to get that into it
• Kline: will consult w/DNS experts in other WGs

Various Draft Status (20 mins)

Speaker(s): Brian Sipos
Document(s): draft-ietf-dtn-bpsec-cose, draft-ietf-dtn-eid-pattern,
draft-ietf-dtn-udpcl, draft-ietf-dtn-bp-sand, draft-sipos-dtn-bp-safe,
draft-sipos-dtn-edge-zeroconf

EID patterns:

• Klein: if anyone demands DTN patterns in EID, tell them to write up
  a proposal on exactly how to do it
• consensus: EID draft should proceed w/IPN patterns only, no DTN
  patterns, get it done, can add DTN patterns in future

UDPCL:

• chairs: need more than 1 implementation to ensure draft enables
  interoperability
• Sipos: that is fair

general:

• Sipos: bpsec-cose & eid-pattern ready for WGLC, other drafts less
  mature
• chairs: take those 2 WGLC call requests & bp-safe adoption request
  to list

DTNMA

Speaker: Justin Ethier
Document(s): draft-ietf-dtn-amm-05, draft-ietf-dtn-ari-06,
draft-ietf-dtn-amp-02

BTP-U (15 mins)

Speaker(s): Rick Taylor
Document(s): draft-ietf-dtn-btpu-00, draft-ietf-dtn-btpu-fec-00

• Sipos: BTPU good but needs framing over Ethernet to enable testing
• Taylor: agreed
• Pelov: why BP over Ethernet
• Taylor: people are asking for it for some use cases inc.
  on-satellite buses
• Kline: suggested expanding "over Ethernet" to "over Ethernet-like
  frames"

BIBE (15 mins)

Speaker(s): Scott Burleigh (in lieue of Joshua Deaton), then Alberto
Montilla
Document(s): draft-ietf-dtn-bibect

• Montilla: will upload slides post presentation
• Montilla: reported experiment ISS<->ground using BIBE etc.
• Montilla: summary of findings: mostly good but...
• Montilla: given mismatched network bandwidths, BIBE Retransmission
  Method tended to flood, so fixes being developed

DTN Architecture BIS (20 mins)

Speaker(s): Scott Burleigh
Document(s): draft-cerf-dtn-4838bis

• Burleigh: move it from IRTF to IETF & update it w/learnings from 18
  years experience
• Burleigh: 2 major changes as follows
• Burleigh: no more custody transfer protocol specifications
• Burleigh: flatten the stack using BP extension blocks rather than
  layers

DTN Resiliency (10 mins)

Speaker(s): Ed Birrane
Document(s): N/A

• Ron in 't Velt: Does your analysis take non-singleton endpoints into
  account?
• Birrane: not yet explicitly, but we should consider that
• Burleigh: w/o timeouts & retransmission, how can you have
  reliability, but they are difficult
• Sipos: measurement is important!
• Fraire: reliability requirements may drive CLP selection?
• Birrane: yes
• Montilla: signaling of desired/offered reliability classes?
• Birrane: yes
• Birrane: will upload draft post presentation

Strong Bundle Audit Mechanism (15 mins)

Speaker(s): Benjamin Dowling (in lieue of Xisen Tian)
Document(s): draft-tian-dtn-sbam

• Dowling: IACR paper analyzed BPSec & proposed "StrongBPSec"
  involving receipts & audits
• Dowling: requests for feedback: unique key IDs, COSE context, new
  block types, excluded blocks, collapse blocks
• Sipos: suggests separation of data & security info using BIB
• chairs: need WG review, suggest renaming "StrongBPSec" to avoid
  unintended inferences

Recharter Discussion (10 mins)

Speaker(s): Chairs
Document(s): N/A

• chairs: out of time for this discussion so go to list

Open Mic (05 mins)

Speaker(s): N/A
Document(s): N/A