Pratyay Mukherjee
@pratyay85.bsky.social
Principal Researcher @ Hashgraph | Interested in Cryptography and Security | https://pratyay.net/
Great program #Nordicrypt_2025
The program for the next NordiCrypt (30/06/2025) is online sites.google.com/view/nordicr...
June 25, 2025 at 3:03 PM
Great program #Nordicrypt_2025
Reposted by Pratyay Mukherjee
Scalable Multiparty Computation from Non-linear Secret Sharing (Sanjam Garg, Abhishek Jain, Pratyay Mukherjee, Mingyuan Wang) ia.cr/2025/1007
June 2, 2025 at 2:11 PM
Scalable Multiparty Computation from Non-linear Secret Sharing (Sanjam Garg, Abhishek Jain, Pratyay Mukherjee, Mingyuan Wang) ia.cr/2025/1007
New work on Verifiable Randomness
InstaRand: Instantly Available and Instantly Verifiable On-chain Randomness (Jacob Gorman, Lucjan Hanzlik, Aniket Kate, Pratyay Mukherjee, Pratik Sarkar, Sri AravindaKrishnan Thyagarajan) ia.cr/2025/896
![Abstract. Web3 applications, such as on-chain gaming, require unbiased and publicly verifiable randomness that can be obtained quickly and cost-effectively whenever needed. Existing services, such as those based on Verifiable Random Functions (VRF), incur network delays and high fees due to their highly interactive nature. FlexiRand [CCS 2023] addressed these problems by hiding the output of the VRF and using that as a seed to derive many randomnesses locally. These randomnesses are instantly available for usage. However, these randomnesses can not be verified independently (or instantly) without disclosing the seed, leaving scope for malicious actors to cheat.
To solve this problem, we introduce a new notion, called instantly-verifiable VRF (iVRF), which enables the generation of many randomnesses from one VRF output seed, such that each of them is verifiable independently - this enables the first solution to cost − effectively generate randomnesses, such that they are instantly available and also independently/instantly verifiable.
To instantiate we propose a generic construction called InstaRand - it combines any (possibly distributed) VRF at the server’s end with another VRF at the client’s end to construct an iVRF. Our specific instantiation uses the BLS-based GLOW-DVRF [Euro S&P 2021] at the server’s end and the DDH-based VRF of Goldberg et al. [RFC 2023] at the client’s end. We use the universal composability framework to analyze the security. Moreover, due to its generality, InstaRand can be instantiated with any post-quantum secure VRF to yield a post-quantum secure iVRF.
Our experiments demonstrate that our instantiation of InstaRand is highly practical. The client incurs a one − time cost to generate the seed (server’s VRF output) by querying the GLOW-dVRF servers once. Once the seed is set up, the client locally generates the pseudorandom value on demand in 0.18 ms, avoiding the client-server round-trip delay. Each value can be independently verified in 0.22 ms. This yields a 400× improvement in terms of output generation and 20× improvement in verification cost over existing solutions.](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:fwa55bujvdrwlwlwgqmmxmuf/bafkreihjxmem35yktb4ht3zqe4xtplbrpgsgc2jclsmehuxiqiix4sqxte@jpeg)
May 24, 2025 at 2:36 PM
New work on Verifiable Randomness
Overleaf is down! Quintessential single point of failure!
May 14, 2025 at 6:33 AM
Overleaf is down! Quintessential single point of failure!
The AI fix feature on @overleaf.com is pretty cool actually, I am loving it so far :-)
(and it's not insanely expensive either)
(and it's not insanely expensive either)
April 14, 2025 at 7:18 AM
The AI fix feature on @overleaf.com is pretty cool actually, I am loving it so far :-)
(and it's not insanely expensive either)
(and it's not insanely expensive either)
Why Bhutan is on the red list? 😶 #travelban
March 16, 2025 at 4:24 AM
Why Bhutan is on the red list? 😶 #travelban
Full version at eprint.iacr.org/2024/1713.pdf
February 26, 2025 at 1:16 PM
Full version at eprint.iacr.org/2024/1713.pdf
New paper PKC'25!
Joint work with Megan Chen (BU), Pousali Dey (ISI), Chaya Ganesh (IISC), Pratik Sarkar (Supra) and Swagata Sasmal (ISI)
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Joint work with Megan Chen (BU), Pousali Dey (ISI), Chaya Ganesh (IISC), Pratik Sarkar (Supra) and Swagata Sasmal (ISI)
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February 26, 2025 at 1:15 PM
New paper PKC'25!
Joint work with Megan Chen (BU), Pousali Dey (ISI), Chaya Ganesh (IISC), Pratik Sarkar (Supra) and Swagata Sasmal (ISI)
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Joint work with Megan Chen (BU), Pousali Dey (ISI), Chaya Ganesh (IISC), Pratik Sarkar (Supra) and Swagata Sasmal (ISI)
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New paper on ePrint on Tracebale CCA-secure Encryptions!
CCA-Secure Traceable Threshold (ID-based) Encryption and Application (Rishiraj Bhattacharyya, Jan Bormet, Sebastian Faust, Pratyay Mukherjee, Hussien Othman) ia.cr/2025/341
![Abstract. A recent work by Boneh, Partap, and Rotem [Crypto’24] introduced the concept of traceable threshold encryption, in that if t or more parties collude to construct a decryption box, which performs decryptions, then at least one party’s identity can be traced by making a few black-box queries to the box. This has important applications, e.g., in blockchain mempool privacy, where collusion yields high financial gain through MEVs without any consequence - the possibility of tracing discourages collusion. Nevertheless, their definitions leave room for exploitation as they only achieve CPA security and do not consider inconsistency in decryption via different participating sets.
This paper proposes stronger definitions of traceable threshold encryption, which supports CCA-security and consistency. Our main approach considers identity-based variants of traceable encryption (which we also define). It converts that to a CCA-secure construction, adapting two generic transformations, first using a one-time signature and then a fingerprinting code. We put forward two efficient instantiations of our identity-based scheme with different merits: our first construction is based on Boneh-Franklin IBE [Crypto’01] and has constant size ciphertexts but quadratic size public keys - this is proven secure based on XDH and BDDH. Our second construction is based on Boneh-Boyen IBE [Eurocrypt’04]. It supports both constant-size ciphertexts and constant-size public keys - this is proven secure based on a variant of the uber assumption over bilinear pairings. Our concrete analysis shows that the first construction’s ciphertext is much (~6x) smaller than the second construction. Finally, we extend the definitions to support consistency and achieve it by adjoining an efficient, non-interactive proof of correct encryption.](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:fwa55bujvdrwlwlwgqmmxmuf/bafkreib5mdsmiwvcylsy3vclhkkkw3hlchnl74vhd26thgldffjwpjyxq4@jpeg)
February 26, 2025 at 1:07 PM
New paper on ePrint on Tracebale CCA-secure Encryptions!
Kolkata Crypto Day (took place on 8th Dec at ISI Kolkata) slides are up!
sites.google.com/d/1Lz8Mff3Uj...
sites.google.com/d/1Lz8Mff3Uj...
Google Drive: Sign-in
Access Google Drive with a Google account (for personal use) or Google Workspace account (for business use).
sites.google.com
February 13, 2025 at 7:09 AM
Kolkata Crypto Day (took place on 8th Dec at ISI Kolkata) slides are up!
sites.google.com/d/1Lz8Mff3Uj...
sites.google.com/d/1Lz8Mff3Uj...
New work on ePrint!
VITARIT: Paying for Threshold Services on Bitcoin and Friends (Lucjan Hanzlik, Aniket Kate, Easwar Vivek Mangipudi, Pratyay Mukherjee, Sri AravindaKrishnan Thyagarajan) ia.cr/2025/174
February 7, 2025 at 10:58 AM
New work on ePrint!
I love this idea!
I recommend no fewer than 4 copies of any beloved book. A paperback for traveling and lending to friends, an eBook for reading with greasy snack fingers, an audio book so you know how the characters' names are actually pronounced, and a pristine hardcover to be buried with you like a pharaoh
December 20, 2024 at 3:40 AM
I love this idea!
Reposted by Pratyay Mukherjee
Submission deadline approaching for the IACR Communications in Cryptology (CiC).
Don’t miss your chance to contribute to this diamond open access journal.
Deadline: January 13, 2025 (AoE)
Details and submission guidelines: cic.iacr.org/callforpapers
#cryptography #iacr
Don’t miss your chance to contribute to this diamond open access journal.
Deadline: January 13, 2025 (AoE)
Details and submission guidelines: cic.iacr.org/callforpapers
#cryptography #iacr
December 13, 2024 at 10:18 AM
Submission deadline approaching for the IACR Communications in Cryptology (CiC).
Don’t miss your chance to contribute to this diamond open access journal.
Deadline: January 13, 2025 (AoE)
Details and submission guidelines: cic.iacr.org/callforpapers
#cryptography #iacr
Don’t miss your chance to contribute to this diamond open access journal.
Deadline: January 13, 2025 (AoE)
Details and submission guidelines: cic.iacr.org/callforpapers
#cryptography #iacr
Thank you! Also hope you enjoyed the boat ride :-) #Asiacrypt2024
It worked out well in the end (even if some people had to find a place that sells button downs last minute), thanks for organizing!
December 13, 2024 at 3:26 AM
Thank you! Also hope you enjoyed the boat ride :-) #Asiacrypt2024
Paul Kocher will deliver an IACR Distinguished Lecture tomorrow at #Asiacrypt2024
December 10, 2024 at 3:24 PM
Paul Kocher will deliver an IACR Distinguished Lecture tomorrow at #Asiacrypt2024
December 10, 2024 at 11:28 AM
#Asiacrypt2024 (Important Change): The welcome reception will take place at the Calcutta Rowing Club (15, Dhakuria, Rabindra Sarobar, Kolkata, West Bengal 700029). Be aware that the venue *dress code* prohibits slippers/flip-flops/open chappals and shirts without collars
December 7, 2024 at 6:50 AM
#Asiacrypt2024 (Important Change): The welcome reception will take place at the Calcutta Rowing Club (15, Dhakuria, Rabindra Sarobar, Kolkata, West Bengal 700029). Be aware that the venue *dress code* prohibits slippers/flip-flops/open chappals and shirts without collars
#Asiacrypt2024 is almost here. As someone who was born and raised in Kolkata, I decided to provide some unofficial updates/tips and will post them as they come into my mind. Folks, especially who are coming from outside the sub-continent, might find these useful.
1/3
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December 6, 2024 at 10:27 AM
#Asiacrypt2024 is almost here. As someone who was born and raised in Kolkata, I decided to provide some unofficial updates/tips and will post them as they come into my mind. Folks, especially who are coming from outside the sub-continent, might find these useful.
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I don’t understand why the hotcrp for IACR conferences always need signing in plus the password autofill never works, unlike for security conferences (CCS, S&P, Usenix) 🥲
November 30, 2024 at 6:24 AM
I don’t understand why the hotcrp for IACR conferences always need signing in plus the password autofill never works, unlike for security conferences (CCS, S&P, Usenix) 🥲
Happening with Asiacrypt
Are you attending Asiacrypt2024? If you are a women-in-cryptography, you can participate in our coffee breaks: docs.google.com/forms/d/e/1F... We will match you with someone and you can grab a coffee/tea in person!
November 28, 2024 at 12:45 PM
Happening with Asiacrypt
Follow this pack to interact with the bsky Cryptography Research community…
Here is a Cryptography starter pack. I've included academics, researchers and journalists. Let me know if you should be included in this. I will not be adding accounts selling products, the focus here is on research and investigative journalism into privacy. Cheers. go.bsky.app/st9dXx
November 28, 2024 at 6:47 AM
Follow this pack to interact with the bsky Cryptography Research community…
Hello bsky world! 👋
November 28, 2024 at 6:00 AM
Hello bsky world! 👋