---
_id: '45891'
author:
- first_name: Johannes
full_name: Blömer, Johannes
id: '23'
last_name: Blömer
- first_name: Fabian
full_name: Eidens, Fabian
id: '25078'
last_name: Eidens
- first_name: Tibor
full_name: Jager, Tibor
id: '64669'
last_name: Jager
- first_name: David
full_name: Niehues, David
id: '36113'
last_name: Niehues
- first_name: Christian
full_name: Scheideler, Christian
id: '20792'
last_name: Scheideler
citation:
ama: 'Blömer J, Eidens F, Jager T, Niehues D, Scheideler C. Robustness and Security.
In: Haake C-J, Meyer auf der Heide F, Platzner M, Wachsmuth H, Wehrheim H, eds.
On-The-Fly Computing -- Individualized IT-Services in Dynamic Markets.
Vol 412. Verlagsschriftenreihe des Heinz Nixdorf Instituts. Heinz Nixdorf Institut,
Universität Paderborn; 2023:145-164. doi:10.5281/zenodo.8068629'
apa: Blömer, J., Eidens, F., Jager, T., Niehues, D., & Scheideler, C. (2023).
Robustness and Security. In C.-J. Haake, F. Meyer auf der Heide, M. Platzner,
H. Wachsmuth, & H. Wehrheim (Eds.), On-The-Fly Computing -- Individualized
IT-services in dynamic markets (Vol. 412, pp. 145–164). Heinz Nixdorf Institut,
Universität Paderborn. https://doi.org/10.5281/zenodo.8068629
bibtex: '@inbook{Blömer_Eidens_Jager_Niehues_Scheideler_2023, place={Paderborn},
series={Verlagsschriftenreihe des Heinz Nixdorf Instituts}, title={Robustness
and Security}, volume={412}, DOI={10.5281/zenodo.8068629},
booktitle={On-The-Fly Computing -- Individualized IT-services in dynamic markets},
publisher={Heinz Nixdorf Institut, Universität Paderborn}, author={Blömer, Johannes
and Eidens, Fabian and Jager, Tibor and Niehues, David and Scheideler, Christian},
editor={Haake, Claus-Jochen and Meyer auf der Heide, Friedhelm and Platzner, Marco
and Wachsmuth, Henning and Wehrheim, Heike}, year={2023}, pages={145–164}, collection={Verlagsschriftenreihe
des Heinz Nixdorf Instituts} }'
chicago: 'Blömer, Johannes, Fabian Eidens, Tibor Jager, David Niehues, and Christian
Scheideler. “Robustness and Security.” In On-The-Fly Computing -- Individualized
IT-Services in Dynamic Markets, edited by Claus-Jochen Haake, Friedhelm Meyer
auf der Heide, Marco Platzner, Henning Wachsmuth, and Heike Wehrheim, 412:145–64.
Verlagsschriftenreihe Des Heinz Nixdorf Instituts. Paderborn: Heinz Nixdorf Institut,
Universität Paderborn, 2023. https://doi.org/10.5281/zenodo.8068629.'
ieee: 'J. Blömer, F. Eidens, T. Jager, D. Niehues, and C. Scheideler, “Robustness
and Security,” in On-The-Fly Computing -- Individualized IT-services in dynamic
markets, vol. 412, C.-J. Haake, F. Meyer auf der Heide, M. Platzner, H. Wachsmuth,
and H. Wehrheim, Eds. Paderborn: Heinz Nixdorf Institut, Universität Paderborn,
2023, pp. 145–164.'
mla: Blömer, Johannes, et al. “Robustness and Security.” On-The-Fly Computing
-- Individualized IT-Services in Dynamic Markets, edited by Claus-Jochen Haake
et al., vol. 412, Heinz Nixdorf Institut, Universität Paderborn, 2023, pp. 145–64,
doi:10.5281/zenodo.8068629.
short: 'J. Blömer, F. Eidens, T. Jager, D. Niehues, C. Scheideler, in: C.-J. Haake,
F. Meyer auf der Heide, M. Platzner, H. Wachsmuth, H. Wehrheim (Eds.), On-The-Fly
Computing -- Individualized IT-Services in Dynamic Markets, Heinz Nixdorf Institut,
Universität Paderborn, Paderborn, 2023, pp. 145–164.'
date_created: 2023-07-07T08:08:47Z
date_updated: 2023-07-07T11:18:21Z
ddc:
- '004'
department:
- _id: '7'
doi: 10.5281/zenodo.8068629
editor:
- first_name: Claus-Jochen
full_name: Haake, Claus-Jochen
last_name: Haake
- first_name: Friedhelm
full_name: Meyer auf der Heide, Friedhelm
last_name: Meyer auf der Heide
- first_name: Marco
full_name: Platzner, Marco
last_name: Platzner
- first_name: Henning
full_name: Wachsmuth, Henning
last_name: Wachsmuth
- first_name: Heike
full_name: Wehrheim, Heike
last_name: Wehrheim
file:
- access_level: open_access
content_type: application/pdf
creator: florida
date_created: 2023-07-07T08:08:37Z
date_updated: 2023-07-07T11:18:21Z
file_id: '45892'
file_name: C1-Chapter-SFB-Buch-Final.pdf
file_size: 320980
relation: main_file
file_date_updated: 2023-07-07T11:18:21Z
has_accepted_license: '1'
intvolume: ' 412'
language:
- iso: eng
oa: '1'
page: 145-164
place: Paderborn
project:
- _id: '1'
grant_number: '160364472'
name: 'SFB 901: SFB 901: On-The-Fly Computing - Individualisierte IT-Dienstleistungen
in dynamischen Märkten '
- _id: '4'
name: 'SFB 901 - C: SFB 901 - Project Area C'
- _id: '13'
name: 'SFB 901 - C1: SFB 901 - Subproject C1'
publication: On-The-Fly Computing -- Individualized IT-services in dynamic markets
publisher: Heinz Nixdorf Institut, Universität Paderborn
series_title: Verlagsschriftenreihe des Heinz Nixdorf Instituts
status: public
title: Robustness and Security
type: book_chapter
user_id: '477'
volume: 412
year: '2023'
...
---
_id: '29763'
abstract:
- lang: eng
text: "Modern-day communication has become more and more digital. While this comes
with many advantages such as a more efficient economy, it has also created more
and more opportunities for various adversaries to manipulate communication or
eavesdrop on it. The Snowden revelations in 2013 further highlighted the seriousness
of these threats. To protect the communication of people, companies, and states
from such threats, we require cryptography with strong security guarantees.\r\nDifferent
applications may require different security properties from cryptographic schemes.
For most applications, however, so-called adaptive security is considered a reasonable
minimal requirement of security. Cryptographic schemes with adaptive security
remain secure in the presence of an adversary that can corrupt communication partners
to respond to messages of the adversaries choice, while the adversary may choose
the messages based on previously observed interactions.\r\nWhile cryptography
is associated the most with encryption, this is only one of many primitives that
are essential for the security of digital interactions. This thesis presents novel
identity-based encryption (IBE) schemes and verifiable random functions (VRFs)
that achieve adaptive security as outlined above. Moreover, the cryptographic
schemes presented in this thesis are proven secure in the standard model. That
is without making use of idealized models like the random oracle model."
author:
- first_name: David
full_name: Niehues, David
id: '36113'
last_name: Niehues
citation:
ama: Niehues D. More Efficient Techniques for Adaptively-Secure Cryptography.;
2022. doi:10.25926/rdtq-jw45
apa: Niehues, D. (2022). More Efficient Techniques for Adaptively-Secure Cryptography.
https://doi.org/10.25926/rdtq-jw45
bibtex: '@book{Niehues_2022, title={More Efficient Techniques for Adaptively-Secure
Cryptography}, DOI={10.25926/rdtq-jw45},
author={Niehues, David}, year={2022} }'
chicago: Niehues, David. More Efficient Techniques for Adaptively-Secure Cryptography,
2022. https://doi.org/10.25926/rdtq-jw45.
ieee: D. Niehues, More Efficient Techniques for Adaptively-Secure Cryptography.
2022.
mla: Niehues, David. More Efficient Techniques for Adaptively-Secure Cryptography.
2022, doi:10.25926/rdtq-jw45.
short: D. Niehues, More Efficient Techniques for Adaptively-Secure Cryptography,
2022.
date_created: 2022-02-07T13:29:07Z
date_updated: 2022-02-07T13:32:28Z
ddc:
- '000'
department:
- _id: '558'
doi: 10.25926/rdtq-jw45
file:
- access_level: closed
content_type: application/pdf
creator: davnie
date_created: 2022-02-07T13:26:05Z
date_updated: 2022-02-07T13:26:05Z
file_id: '29764'
file_name: de2107.pdf
file_size: 1542089
relation: main_file
success: 1
file_date_updated: 2022-02-07T13:26:05Z
has_accepted_license: '1'
keyword:
- public-key cryptography
- lattices
- pairings
- verifiable random functions
- identity-based encryption
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://elpub.bib.uni-wuppertal.de/servlets/DerivateServlet/Derivate-14686/de2107.pdf
oa: '1'
project:
- _id: '1'
name: 'SFB 901: SFB 901'
- _id: '4'
name: 'SFB 901 - C: SFB 901 - Project Area C'
- _id: '13'
name: 'SFB 901 - C1: SFB 901 - Subproject C1'
publication_status: published
status: public
supervisor:
- first_name: Tibor
full_name: Jager, Tibor
id: '64669'
last_name: Jager
- first_name: Anja
full_name: Lehmann, Anja
last_name: Lehmann
title: More Efficient Techniques for Adaptively-Secure Cryptography
type: dissertation
user_id: '36113'
year: '2022'
...
---
_id: '22057'
abstract:
- lang: eng
text: "We construct more efficient cryptosystems with provable\r\nsecurity against
adaptive attacks, based on simple and natural hardness\r\nassumptions in the standard
model. Concretely, we describe:\r\n– An adaptively-secure variant of the efficient,
selectively-secure LWE-\r\nbased identity-based encryption (IBE) scheme of Agrawal,
Boneh,\r\nand Boyen (EUROCRYPT 2010). In comparison to the previously\r\nmost
efficient such scheme by Yamada (CRYPTO 2017) we achieve\r\nsmaller lattice parameters
and shorter public keys of size O(log λ),\r\nwhere λ is the security parameter.\r\n–
Adaptively-secure variants of two efficient selectively-secure pairing-\r\nbased
IBEs of Boneh and Boyen (EUROCRYPT 2004). One is based\r\non the DBDH assumption,
has the same ciphertext size as the cor-\r\nresponding BB04 scheme, and achieves
full adaptive security with\r\npublic parameters of size only O(log λ). The other
is based on a q-\r\ntype assumption and has public key size O(λ), but a ciphertext
is\r\nonly a single group element and the security reduction is quadrat-\r\nically
tighter than the corresponding scheme by Jager and Kurek\r\n(ASIACRYPT 2018).\r\n–
A very efficient adaptively-secure verifiable random function where\r\nproofs,
public keys, and secret keys have size O(log λ).\r\nAs a technical contribution
we introduce blockwise partitioning, which\r\nleverages the assumption that a
cryptographic hash function is weak\r\nnear-collision resistant to prove full
adaptive security of cryptosystems."
author:
- first_name: Tibor
full_name: Jager, Tibor
last_name: Jager
- first_name: Rafael
full_name: Kurek, Rafael
last_name: Kurek
- first_name: David
full_name: Niehues, David
id: '36113'
last_name: Niehues
citation:
ama: 'Jager T, Kurek R, Niehues D. Efficient Adaptively-Secure IB-KEMs and VRFs
via Near-Collision Resistance. In: Public-Key Cryptography – PKC 2021.
Cham; 2021. doi:10.1007/978-3-030-75245-3_22'
apa: Jager, T., Kurek, R., & Niehues, D. (2021). Efficient Adaptively-Secure
IB-KEMs and VRFs via Near-Collision Resistance. In Public-Key Cryptography
– PKC 2021. Cham. https://doi.org/10.1007/978-3-030-75245-3_22
bibtex: '@inbook{Jager_Kurek_Niehues_2021, place={Cham}, title={Efficient Adaptively-Secure
IB-KEMs and VRFs via Near-Collision Resistance}, DOI={10.1007/978-3-030-75245-3_22},
booktitle={Public-Key Cryptography – PKC 2021}, author={Jager, Tibor and Kurek,
Rafael and Niehues, David}, year={2021} }'
chicago: Jager, Tibor, Rafael Kurek, and David Niehues. “Efficient Adaptively-Secure
IB-KEMs and VRFs via Near-Collision Resistance.” In Public-Key Cryptography
– PKC 2021. Cham, 2021. https://doi.org/10.1007/978-3-030-75245-3_22.
ieee: T. Jager, R. Kurek, and D. Niehues, “Efficient Adaptively-Secure IB-KEMs and
VRFs via Near-Collision Resistance,” in Public-Key Cryptography – PKC 2021,
Cham, 2021.
mla: Jager, Tibor, et al. “Efficient Adaptively-Secure IB-KEMs and VRFs via Near-Collision
Resistance.” Public-Key Cryptography – PKC 2021, 2021, doi:10.1007/978-3-030-75245-3_22.
short: 'T. Jager, R. Kurek, D. Niehues, in: Public-Key Cryptography – PKC 2021,
Cham, 2021.'
date_created: 2021-05-10T15:56:24Z
date_updated: 2022-01-06T06:55:23Z
ddc:
- '000'
department:
- _id: '558'
doi: 10.1007/978-3-030-75245-3_22
file:
- access_level: closed
content_type: application/pdf
creator: davnie
date_created: 2021-05-10T16:02:02Z
date_updated: 2021-05-10T16:02:02Z
file_id: '22058'
file_name: Jager et al. - 2021 - Efficient Adaptively-Secure IB-KEMs and VRFs via
N.pdf
file_size: 701068
relation: main_file
file_date_updated: 2021-05-10T16:02:02Z
has_accepted_license: '1'
language:
- iso: eng
place: Cham
project:
- _id: '1'
name: SFB 901
- _id: '4'
name: SFB 901 - Project Area C
- _id: '13'
name: SFB 901 - Subproject C1
publication: Public-Key Cryptography – PKC 2021
publication_identifier:
isbn:
- '9783030752446'
- '9783030752453'
issn:
- 0302-9743
- 1611-3349
publication_status: published
status: public
title: Efficient Adaptively-Secure IB-KEMs and VRFs via Near-Collision Resistance
type: book_chapter
user_id: '36113'
year: '2021'
...
---
_id: '22059'
abstract:
- lang: eng
text: "Verifiable random functions (VRFs), introduced by Micali,\r\nRabin and Vadhan
(FOCS’99), are the public-key equivalent of pseudo-\r\nrandom functions. A public
verification key and proofs accompanying the\r\noutput enable all parties to verify
the correctness of the output. How-\r\never, all known standard model VRFs have
a reduction loss that is much\r\nworse than what one would expect from known optimal
constructions of\r\nclosely related primitives like unique signatures. We show
that:\r\n1. Every security proof for a VRF that relies on a non-interactive\r\nassumption
has to lose a factor of Q, where Q is the number of adver-\r\nsarial queries.
To that end, we extend the meta-reduction technique\r\nof Bader et al. (EUROCRYPT’16)
to also cover VRFs.\r\n2. This raises the question: Is this bound optimal? We
answer this ques-\r\ntion in the affirmative by presenting the first VRF with
a reduction\r\nfrom the non-interactive qDBDHI assumption to the security of VRF\r\nthat
achieves this optimal loss.\r\nWe thus paint a complete picture of the achievability
of tight verifiable\r\nrandom functions: We show that a security loss of Q is
unavoidable and\r\npresent the first construction that achieves this bound."
author:
- first_name: David
full_name: Niehues, David
id: '36113'
last_name: Niehues
citation:
ama: 'Niehues D. Verifiable Random Functions with Optimal Tightness. In: Public-Key
Cryptography – PKC 2021. Cham; 2021. doi:10.1007/978-3-030-75248-4_3'
apa: Niehues, D. (2021). Verifiable Random Functions with Optimal Tightness. In
Public-Key Cryptography – PKC 2021. Cham. https://doi.org/10.1007/978-3-030-75248-4_3
bibtex: '@inbook{Niehues_2021, place={Cham}, title={Verifiable Random Functions
with Optimal Tightness}, DOI={10.1007/978-3-030-75248-4_3},
booktitle={Public-Key Cryptography – PKC 2021}, author={Niehues, David}, year={2021}
}'
chicago: Niehues, David. “Verifiable Random Functions with Optimal Tightness.” In
Public-Key Cryptography – PKC 2021. Cham, 2021. https://doi.org/10.1007/978-3-030-75248-4_3.
ieee: D. Niehues, “Verifiable Random Functions with Optimal Tightness,” in Public-Key
Cryptography – PKC 2021, Cham, 2021.
mla: Niehues, David. “Verifiable Random Functions with Optimal Tightness.” Public-Key
Cryptography – PKC 2021, 2021, doi:10.1007/978-3-030-75248-4_3.
short: 'D. Niehues, in: Public-Key Cryptography – PKC 2021, Cham, 2021.'
date_created: 2021-05-10T16:07:50Z
date_updated: 2022-01-06T06:55:24Z
ddc:
- '000'
department:
- _id: '558'
doi: 10.1007/978-3-030-75248-4_3
file:
- access_level: closed
content_type: application/pdf
creator: davnie
date_created: 2021-05-10T16:09:17Z
date_updated: 2021-05-10T16:09:17Z
file_id: '22060'
file_name: Niehues - 2021 - Verifiable Random Functions with Optimal Tightness.pdf
file_size: 697361
relation: main_file
file_date_updated: 2021-05-10T16:09:17Z
has_accepted_license: '1'
language:
- iso: eng
place: Cham
project:
- _id: '1'
name: SFB 901
- _id: '4'
name: SFB 901 - Project Area C
- _id: '13'
name: SFB 901 - Subproject C1
publication: Public-Key Cryptography – PKC 2021
publication_identifier:
isbn:
- '9783030752477'
- '9783030752484'
issn:
- 0302-9743
- 1611-3349
publication_status: published
status: public
title: Verifiable Random Functions with Optimal Tightness
type: book_chapter
user_id: '36113'
year: '2021'
...
---
_id: '21396'
abstract:
- lang: eng
text: "Verifiable random functions (VRFs) are essentially digital signatures with
additional properties, namely verifiable uniqueness and pseudorandomness, which
make VRFs a useful tool, e.g., to prevent enumeration in DNSSEC Authenticated
Denial of Existence and the CONIKS key management system, or in the random committee
selection of the Algorand blockchain.\r\n\r\nMost standard-model VRFs rely on
admissible hash functions (AHFs) to achieve security against adaptive attacks
in the standard model. Known AHF constructions are based on error-correcting codes,
which yield asymptotically efficient constructions. However, previous works do
not clarify how the code should be instantiated concretely in the real world.
The rate and the minimal distance of the selected code have significant impact
on the efficiency of the resulting cryptosystem, therefore it is unclear if and
how the aforementioned constructions can be used in practice.\r\n\r\nFirst, we
explain inherent limitations of code-based AHFs. Concretely, we assume that even
if we were given codes that achieve the well-known Gilbert-Varshamov or McEliece-Rodemich-Rumsey-Welch
bounds, existing AHF-based constructions of verifiable random functions (VRFs)
can only be instantiated quite inefficiently. Then we introduce and construct
computational AHFs (cAHFs). While classical AHFs are information-theoretic, and
therefore work even in presence of computationally unbounded adversaries, cAHFs
provide only security against computationally bounded adversaries. However, we
show that cAHFs can be instantiated significantly more efficiently. Finally, we
use our cAHF to construct the currently most efficient verifiable random function
with full adaptive security in the standard model."
author:
- first_name: Tibor
full_name: Jager, Tibor
last_name: Jager
- first_name: David
full_name: Niehues, David
id: '36113'
last_name: Niehues
citation:
ama: 'Jager T, Niehues D. On the Real-World Instantiability of Admissible Hash Functions
and Efficient Verifiable Random Functions. In: Lecture Notes in Computer Science.
Cham; 2020. doi:10.1007/978-3-030-38471-5_13'
apa: Jager, T., & Niehues, D. (2020). On the Real-World Instantiability of Admissible
Hash Functions and Efficient Verifiable Random Functions. In Lecture Notes
in Computer Science. Cham. https://doi.org/10.1007/978-3-030-38471-5_13
bibtex: '@inbook{Jager_Niehues_2020, place={Cham}, title={On the Real-World Instantiability
of Admissible Hash Functions and Efficient Verifiable Random Functions}, DOI={10.1007/978-3-030-38471-5_13},
booktitle={Lecture Notes in Computer Science}, author={Jager, Tibor and Niehues,
David}, year={2020} }'
chicago: Jager, Tibor, and David Niehues. “On the Real-World Instantiability of
Admissible Hash Functions and Efficient Verifiable Random Functions.” In Lecture
Notes in Computer Science. Cham, 2020. https://doi.org/10.1007/978-3-030-38471-5_13.
ieee: T. Jager and D. Niehues, “On the Real-World Instantiability of Admissible
Hash Functions and Efficient Verifiable Random Functions,” in Lecture Notes
in Computer Science, Cham, 2020.
mla: Jager, Tibor, and David Niehues. “On the Real-World Instantiability of Admissible
Hash Functions and Efficient Verifiable Random Functions.” Lecture Notes in
Computer Science, 2020, doi:10.1007/978-3-030-38471-5_13.
short: 'T. Jager, D. Niehues, in: Lecture Notes in Computer Science, Cham, 2020.'
conference:
end_date: 2019-08-16
location: Waterloo, Canada
name: Selected Areas in Cryptography
start_date: 2019-08-12
date_created: 2021-03-08T16:50:31Z
date_updated: 2022-01-06T06:54:58Z
ddc:
- '000'
department:
- _id: '558'
doi: 10.1007/978-3-030-38471-5_13
file:
- access_level: closed
content_type: application/pdf
creator: davnie
date_created: 2021-03-08T17:02:37Z
date_updated: 2021-03-08T17:02:37Z
file_id: '21399'
file_name: Jager und Niehues - 2020 - On the Real-World Instantiability of Admissible
Ha.pdf
file_size: 706743
relation: main_file
file_date_updated: 2021-03-08T17:02:37Z
has_accepted_license: '1'
keyword:
- Admissible hash functions
- Verifiable random functions
- Error-correcting codes
- Provable security
language:
- iso: eng
main_file_link:
- url: https://link.springer.com/content/pdf/10.1007%252F978-3-030-38471-5_13.pdf
place: Cham
project:
- _id: '1'
name: SFB 901
- _id: '4'
name: SFB 901 - Project Area C
- _id: '13'
name: SFB 901 - Subproject C1
publication: Lecture Notes in Computer Science
publication_identifier:
isbn:
- '9783030384708'
- '9783030384715'
issn:
- 0302-9743
- 1611-3349
publication_status: published
quality_controlled: '1'
related_material:
link:
- relation: later_version
url: https://eprint.iacr.org/2019/1335.pdf
status: public
title: On the Real-World Instantiability of Admissible Hash Functions and Efficient
Verifiable Random Functions
type: book_chapter
user_id: '36113'
year: '2020'
...