Opened 8 years ago

Closed 8 years ago

Last modified 8 years ago

#4679 closed project (fixed)

Design a pluggable transport roadmap

Reported by: karsten Owned by: sjmurdoch
Priority: Medium Milestone:
Component: Circumvention/Pluggable transport Version:
Severity: Keywords: SponsorF20120315
Cc: asn, nickm, zwol, blanu, arma Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description (last modified by phobos)

"Disambiguation" note: This ticket is about comparing pluggable transport protocols, not about writing down the steps for deploying pluggable transports (#4562).

For sponsor F deliverable 6 we promised to "help SponsorF design a roadmap for the scope of transports we expect need work." This deliverable comprises the following tasks:

  • Talk to SponsorF about the prototypes of various pluggable transports they came up with and include them in the roadmap.
  • Describe what security properties each of the transports aims to provide (i.e. what censorship techniques it aims to defeat).
  • Figure out how far along we are at each of them and what research and development roadblocks remain.
  • Prioritize transports by complexity and urgency of deployment.
  • Build a plan for how to compose transports appropriately without screwing up their properties.
  • For each transport, speculate about how easy and/or smart it would be to bake into Tor itself.

Optimistically assigning this ticket to Steven, because he said he might be able to lead this deliverable. This deliverable needs input from many Tor developers.

Child Tickets

Attachments (1)

pluggable-roadmap.pdf (72.0 KB) - added by asn 8 years ago.

Download all attachments as: .zip

Change History (10)

comment:1 Changed 8 years ago by karsten

Cc: zwol blanu added

Adding zwol and blanu to Cc, because I was told they have valuable input on the topic.

comment:2 Changed 8 years ago by karsten

Cc: arma added

Did I forget to cc Roger? Oops.

comment:3 Changed 8 years ago by phobos

Description: modified (diff)

comment:4 Changed 8 years ago by sjmurdoch

Resolution: fixed
Status: newclosed

The roadmap can be found as a PDF and in git (branch project4679, commit bb207c619310e450060ce39d6343c4742f26488f).

In summary:

Of the currently available pluggable transports, obfs2 is a good default due to its efficiency and resistance to blocking. StegoTorus offers alternative pluggable transports which are significantly harder to block, but come with a much higher overhead. Suggestions for future development include: efficiency improvements, splitting and joining Tor cells to disguise Tor's distinctive packet-size probability distribution, efficient ways to hide ciphertext in compressed data, hardening obfs2 against a passive adversary, and designing a HTTP transport capable of traversing a proxy server.

comment:5 Changed 8 years ago by asn

I added two sections to the document. They talk about bananaphone and stupid transports like base64. You can find the changes in project4679 in

I'm also attaching the updated PDF:

Changed 8 years ago by asn

Attachment: pluggable-roadmap.pdf added

comment:6 Changed 8 years ago by karsten

So, which PDF should we link from the wiki page? We're currently linking to Steven's PDF there.

comment:7 in reply to:  6 Changed 8 years ago by sjmurdoch

Replying to karsten:

So, which PDF should we link from the wiki page? We're currently linking to Steven's PDF there.

I've replaced my PDF with the one that George attached, so we can continue linking to my one.

comment:8 Changed 8 years ago by sjmurdoch

I've merged George's changes into git and also added him as an author. George, let me know if this isn't OK.

comment:9 Changed 8 years ago by karsten

Keywords: SponsorF20120315 added
Milestone: Sponsor F: March 15, 2012

Switching from using milestones to keywords for sponsor deliverables. See #6365 for details.

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