More from @ittaia

Sep 14, 2024

“Even if MPC works you still need TEEs”

Pioneer blockchain researcher @socrates1024 in a great podcast about TEEs 🔥

Some of my notes ⤵️

https://twitter.com/zeroknowledgefm/status/1833876724901138611

1. Must watch explanation about delegation and encumbrance - this is clearly going to be a major future use case. Wonderful clarity around ZK enabling read permissions vs TEE also enabling smart contract based write permissions

ZK, TEEs and MPC will all play a major role here

2. People who don’t understand consensus continue to not understand consensus 😃 A bit disappointed that Andrew did not push back - not to mention cases where TEEs improve BFT and where BFT improve TEEs...

Read 6 tweets

Jan 23, 2024

1/4 Motorway: a new super high throughput and low latency BFT system that is **not a DAG** by lead authors Neil Giridharan and Florian Suri-Payer !!

arxiv.org/abs/2401.10369

2/4 BFT systems in partial synchrony loose liveness in asynchrony and regain it once synchrony comes back.

But when operating on constant load most systems suffer a **hangover** - they have to spend considerable time catching up on all the transactions they could not process.

3/4 Motorway experiences no hangover because it can make data dissemination progress during asynchrony and then can instantly commit the entire backlog as soon as synchrony returns.

Some DAG BFT also obtain this property but suffer from higher latency

Read 4 tweets

Jan 10, 2024

Decentralized Thoughts: we are nearing 5 years and 100+ posts!

A few updates for this year 🧵

First, check out the awesome post by Ling Ren on a Simpler Security proof for Nakamoto Consensus

It’s amazing that Bitcoin is 15 years old and it took so long to get clear security proofs for it

decentralizedthoughts.github.io/2023-10-30-Ana…

Gilad Stren on Gather with Binding and Verifiability

Gather is emerging as a core building block in asynchrony - Gilad’s post explains how to obtain the super important properties of Binding and Verifiability in the information theoretic setting!

decentralizedthoughts.github.io/2024-01-09-gat…

Read 8 tweets

Apr 24, 2023

1/From the seminal work of BGW88 and CCD88 we know that perfectly secure (unbounded adversary - just private channels) optimally-resilient (t<n/3) secure Multi-Party Computation (MPC) is possible. But is it efficient?

2/ For a circuit with depth d, there are, in general, two families of protocols: 1. Efficient but slow: O(n) words per gate, but O(n+d) rounds 2. Fast but not efficient: O(d) expected rounds, but O(n^4) words per gate Can we get the best of worlds?

3/ In new work by lead author Shravani Patil with co-authors Gilad Asharov and Arpita Patra we answer this question affirmatively! (accepted to Eurocrypt 2023)

O(n) words per gate and O(d) expected rounds eprint.iacr.org/2023/557.pdf

Read 10 tweets

Jan 28, 2023

1/5 Chained Byzantine Fault Tolerant systems leverage pipelining and leader rotation for efficiency and fairness. Pipelining significantly increases throughput. Leader rotation means that each chosen leader speaks only once, significantly reducing risk of bribery and attacks

2/5 Existing protocols require a sequence of three **consecutive** honest leaders to commit. Even simple leader crashes weaken liveness in theory and practice. Obtaining chained BFT that commits even if the sequence of honest leaders is non-consecutive, remains an open question

3/5 In work led by Neil Giridharan, with @siobhcroo, @heidiann360 and Florian Suri-Payer we resolve this question via a new chained BFT protocol called BeeGees that successfully commits blocks even with non-consecutive honest leaders

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Jan 25, 2023

1/5 View synchronisation is an important component of many modern Byzantine Fault Tolerant State Machine Replication (SMR) systems in the partial synchrony model. The efficiency of view synchronisation has emerged as a bottleneck in the efficiency of SMR systems as a whole

2/5 A key question remained open: Do there exist view synchronisation protocols with asymptotically optimal quadratic worst-case word complexity that also obtain linear message complexity and responsiveness when moving between consecutive correct leaders?

3/5 In work led by @AndrewLewisPye, we answer this question affirmatively with a new view synchronisation protocol for partial synchrony assuming minimal clock synchronisation, called Fever 🔥🔥🔥

Read 5 tweets