Workshop on Security of Permissionless Systems

Permissionless systems allow nodes to join and depart without centralized control; they include such new systems as: distributed ledgers, IoT, smart grid, and robot networks, along with older distributed systems such as peer-to-peer and ad-hoc wireless networks. These systems must cope with security threats that arise from an absence of administrative control, and a lack of trust between a dynamic set of participants.

The Workshop on Security of Permissionless Systems (SPS) is dedicated to addressing the application of new tools and adaptation of traditional tools in order to ensure security of permissionless systems. The workshop is a one-day event that will consist of invited speakers presenting on results of interest to the broad community of distributed-computing researchers. Time will also be allocated for the discussion of open problems and future research directions.

Schedule

8:50am - 9:20am: Kevin Sekniqi

9:20am - 9:50am: Maurice Herlihy

9:50am - 10:20am: Nitin Vaidya

10:20am - 10:50am: Coffee Break

10:50am - 11:20am: Diksha Gupta

11:20am - 11:50am: Aniket Kate

11:50am - 12:35pm: Round Table Discussion

12:35pm - 1:20pm: Lunch (in the Mandarin Foyer)

1:20pm - 1:50pm: Mahnush Movahedi

1:50pm - 2:20pm: Valerie King

2:20pm - 2:50pm: Gopal Pandurangan


Details

SPS 2019 will be held on August 2, 2019 in Toronto, ON, Canada, and will be co-located with the ACM Symposium on Principles of Distributed Computing (PODC 2019).

The workshop is a one-day event that will consist of invited speakers presenting on results of interest to the broad community of distributed-computing researchers. Time will also be allocated for the discussion of open problems and future research directions.

Topics of interest include the following:

(1) Constrained Resources. Certain types of permissionless systems such as ad hoc wireless, robot and IoT networks, often face limitations on computational power, bandwidth, and energy, in addition to unreliable communication. Ensuring security in such networks has been an enduring challenge. Can we adapt emerging tools that have been successful in distributed ledgers to these networks, such as proof-of-work (PoW) and proof-of-stake (PoS)?

(2) Resource Testing. Does the success of distributed ledgers justify a renewed interest in PoW-based defenses for traditional threats to permissionless systems such as the Sybil attack, distributed denial-of-service (DDoS) attacks, and routing/eclipse attacks? Can cost relationships between attackers and defenders, be used to achieve high security in modern systems? What are the appropriate models -- in terms of computation, communication, and adversarial power -- for use in designing algorithms that utilize PoW (or PoS) to mitigate these attacks?

(3) Game-Theoretic Approaches. Is there a way to incentivize micropayment-based (PoW/PoS) non-cryptocurrency applications in permissionless systems. In particular, can we create permissionless systems to maintain a distributed ledger, even when there is no currency available to pay participants to help in maintaining the system?

(4) Handling Churn. In permissionless systems, attackers and defenders continually join and depart. Thus, the adversary is neither static nor adaptive. Moreover, there is a need to efficiently incorporate new defenders into the system, and seamlessly handle their unpredictable departures. How should we define formal security problems in this new domain? In particular, how can we do this for new problems such as maintaining a distributed ledger and enabling smart contracts/secure multiparty computation (MPC)?

Invited Speakers

Maurice Herlihy, Brown University
Aniket Kate, Purdue University
Valerie King, University of Victoria
Mahnush Movahedi, DFINITY
Gopal Pandurangan, University of Houston
Kevin Sekniqi, Ava Labs
Nitin Vaidya, Georgetown University

Organizers

Diksha Gupta, University of New Mexico
Jared Saia, University of New Mexico
Maxwell Young, Mississippi State University