Philipp Jovanovic
YOU?
Author Swipe
View article: Mahi-Mahi: Low-Latency Asynchronous BFT DAG-Based Consensus
Mahi-Mahi: Low-Latency Asynchronous BFT DAG-Based Consensus Open
We present Mahi-Mahi, the first asynchronous BFT consensus protocol that achieves sub-second latency in the WAN while processing over 100,000 transactions per second. We accomplish this remarkable performance by building Mahi-Mahi on an un…
View article: Zero-Knowledge Location Privacy via Accurate Floating-Point SNARKs
Zero-Knowledge Location Privacy via Accurate Floating-Point SNARKs Open
We introduce Zero-Knowledge Location Privacy (ZKLP), enabling users to prove to third parties that they are within a specified geographical region while not disclosing their exact location. ZKLP supports varying levels of granularity, allo…
View article: From HODL to MOON: Understanding Community Evolution, Emotional Dynamics, and Price Interplay in the Cryptocurrency Ecosystem
From HODL to MOON: Understanding Community Evolution, Emotional Dynamics, and Price Interplay in the Cryptocurrency Ecosystem Open
This paper presents a large-scale analysis of the cryptocurrency community on Reddit, shedding light on the intricate relationship between the evolution of their activity, emotional dynamics, and price movements. We analyze over 130M posts…
View article: QuePaxa: Escaping the tyranny of timeouts in consensus
QuePaxa: Escaping the tyranny of timeouts in consensus Open
Leader-based consensus algorithms are fast and efficient under normal conditions, but lack robustness to adverse conditions due to their reliance on timeouts for liveness. We present QuePaxa, the first protocol offering state-of-the-art no…
View article: Performance of EdDSA and BLS Signatures in Committee-Based Consensus
Performance of EdDSA and BLS Signatures in Committee-Based Consensus Open
We present the first performance comparison of EdDSA and BLS signatures in committee-based consensus protocols through large-scale geo-distributed benchmarks. Contrary to popular beliefs, we find that small deployments (less than 40 valida…
View article: What Drives the (In)stability of a Stablecoin?
What Drives the (In)stability of a Stablecoin? Open
In May 2022, an apparent speculative attack, followed by market panic, led to the precipitous downfall of UST, one of the most popular stablecoins at that time. However, UST is not the only stablecoin to have been depegged in the past. Des…
View article: Mitigating Decentralized Finance Liquidations with Reversible Call Options
Mitigating Decentralized Finance Liquidations with Reversible Call Options Open
Liquidations in Decentralized Finance (DeFi) are both a blessing and a curse -- whereas liquidations prevent lenders from capital loss, they simultaneously lead to liquidation spirals and system-wide failures. Since most lending and borrow…
View article: Performance of EdDSA and BLS Signatures in Committee-Based Consensus
Performance of EdDSA and BLS Signatures in Committee-Based Consensus Open
We present the first performance comparison of EdDSA and BLS signatures in committee-based consensus protocols through large-scale geo-distributed benchmarks. Contrary to popular beliefs, we find that small deployments (less than 40 valida…
View article: Baxos: Backing off for Robust and Efficient Consensus
Baxos: Backing off for Robust and Efficient Consensus Open
Leader-based consensus algorithms are vulnerable to liveness and performance downgrade attacks. We explore the possibility of replacing leader election in Multi-Paxos with random exponential backoff (REB), a simpler approach that requires …
View article: An empirical study of DeFi liquidations
An empirical study of DeFi liquidations Open
Financial speculators often seek to increase their potential gains
\nwith leverage. Debt is a popular form of leverage, and with over
\n39.88B USD of total value locked (TVL), the Decentralized Finance
\n(DeFi) lending markets are thriving…
View article: An Empirical Study of DeFi Liquidations: Incentives, Risks, and Instabilities
An Empirical Study of DeFi Liquidations: Incentives, Risks, and Instabilities Open
Financial speculators often seek to increase their potential gains with leverage. Debt is a popular form of leverage, and with over 39.88B USD of total value locked (TVL), the Decentralized Finance (DeFi) lending markets are thriving. Debt…
View article: Reaching Consensus for Asynchronous Distributed Key Generation
Reaching Consensus for Asynchronous Distributed Key Generation Open
We give a protocol for Asynchronous Distributed Key Generation (A-DKG) that is optimally resilient (can withstand $f
View article: CALYPSO
CALYPSO Open
Distributed ledgers provide high availability and integrity , making them a key enabler for practical and secure computation of distributed workloads among mutually distrustful parties. Many practical applications also require strong confi…
View article: Que Sera Consensus: Simple Asynchronous Agreement with Private Coins and Threshold Logical Clocks
Que Sera Consensus: Simple Asynchronous Agreement with Private Coins and Threshold Logical Clocks Open
It is commonly held that asynchronous consensus is much more complex, difficult, and costly than partially-synchronous algorithms, especially without using common coins. This paper challenges that conventional wisdom with que sera consensu…
View article: OmniLedger: A Secure, Scale-Out, Decentralized Ledger via Sharding
OmniLedger: A Secure, Scale-Out, Decentralized Ledger via Sharding Open
Designing a secure permissionless distributed ledger (blockchain) that performs on par with centralized payment processors, such as Visa, is a challenging task. Most existing distributed ledgers are unable to scale-out, i.e., to grow their…
View article: On Enforcing the Digital Immunity of a Large Humanitarian Organization
On Enforcing the Digital Immunity of a Large Humanitarian Organization Open
Humanitarian action, the process of aiding individuals in situations of crises, poses unique information-security challenges due to natural or manmade disasters, the adverse environments in which it takes place, and the scale and multidisc…
View article: Nonce-Disrespecting Adversaries:Practical Forgery Attacks on GCM in TLS
Nonce-Disrespecting Adversaries:Practical Forgery Attacks on GCM in TLS Open
We investigate nonce reuse issues with the GCM block cipher mode as used in TLS and focus in particular on AES-GCM, the most widely deployed variant. With an Internet-wide scan we identified 184 HTTPS servers repeating nonces, which fully …
View article: Scalable Bias-Resistant Distributed Randomness
Scalable Bias-Resistant Distributed Randomness Open
Bias-resistant public randomness is a critical component in many (distributed) protocols. Existing solutions do not scale to hundreds or thousands of participants, as is needed in many decentralized systems. We propose two large-scale dist…
View article: Proof-of-Personhood: Redemocratizing Permissionless Cryptocurrencies
Proof-of-Personhood: Redemocratizing Permissionless Cryptocurrencies Open
Permissionless blockchain-based cryptocurrencies commonly use proof-of-work (PoW) or proof-of-stake (PoS) to ensure their security, e.g. to prevent double spending attacks. However, both approaches have disadvantages: PoW leads to massive …
View article: CHAINIAC: Proactive Software-Update Transparency via Collectively Signed Skipchains and Verified Builds
CHAINIAC: Proactive Software-Update Transparency via Collectively Signed Skipchains and Verified Builds Open
Software-update mechanisms are critical to the security of modern systems, but their typically centralized design presents a lucrative and frequently attacked target. In this work, we propose CHAINIAC, a decentralized software-update frame…
View article: Keeping Authorities "Honest or Bust" with Decentralized Witness Cosigning
Keeping Authorities "Honest or Bust" with Decentralized Witness Cosigning Open
The secret keys of critical network authorities - such as time, name, certificate, and software update services - represent high-value targets for hackers, criminals, and spy agencies wishing to use these keys secretly to compromise other …
View article: Enhancing Bitcoin Security and Performance with Strong Consistency via Collective Signing
Enhancing Bitcoin Security and Performance with Strong Consistency via Collective Signing Open
While showing great promise, Bitcoin requires users to wait tens of minutes for transactions to commit, and even then, offering only probabilistic guarantees. This paper introduces ByzCoin, a novel Byzantine consensus protocol that leverag…
View article: Enhancing Bitcoin Security and Performance with Strong Consistency via\n Collective Signing
Enhancing Bitcoin Security and Performance with Strong Consistency via\n Collective Signing Open
While showing great promise, Bitcoin requires users to wait tens of minutes\nfor transactions to commit, and even then, offering only probabilistic\nguarantees. This paper introduces ByzCoin, a novel Byzantine consensus protocol\nthat leve…
View article: Keeping Authorities âHonest or Bustâ with Decentralized Witness Cosigning
Keeping Authorities âHonest or Bustâ with Decentralized Witness Cosigning Open
âThe secret keys of critical network authorities â such as time, name, certificate, and software update services â represent high-value targets for hackers, criminals, and spy agencies wishing to use these keys secretly to compromise…
View article: Managing Identities Using Blockchains and CoSi
Managing Identities Using Blockchains and CoSi Open
We combine collective signing and blockchains to create a secure and easy-to-use, decentralized SSH-key management system.
View article: Keeping Authorities "Honest or Bust" with Decentralized Witness\n Cosigning
Keeping Authorities "Honest or Bust" with Decentralized Witness\n Cosigning Open
The secret keys of critical network authorities - such as time, name,\ncertificate, and software update services - represent high-value targets for\nhackers, criminals, and spy agencies wishing to use these keys secretly to\ncompromise oth…
View article: Analysis and Design of Symmetric Cryptographic Algorithms
Analysis and Design of Symmetric Cryptographic Algorithms Open
This doctoral thesis is dedicated to the analysis and the design of
symmetric cryptographic algorithms.
In the first part of the dissertation, we deal with fault-based attacks
on cryptographic circuits which belong to the field of act…