Saved in:
Bibliographic Details
Main Authors: Suda, So, Watanabe, Shun
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2501.11883
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910922171219968
author Suda, So
Watanabe, Shun
author_facet Suda, So
Watanabe, Shun
contents We consider the oblivious transfer (OT) capacities of noisy channels against the passive adversary; this problem has not been solved even for the binary symmetric channel (BSC). In the literature, the general construction of OT has been known only for generalized erasure channels (GECs); for the BSC, we convert the channel to the binary symmetric erasure channel (BSEC), which is a special instance of the GEC, via alphabet extension and erasure emulation. In a previous paper by the authors, we derived an improved lower bound on the OT capacity of BSC by proposing a method to recursively emulate BSEC via interactive communication. In this paper, we introduce two new ideas of OT construction: (i) via ``polarization" and interactive communication, we recursively emulate GECs that are not necessarily a BSEC; (ii) in addition to the GEC emulation part, we also utilize interactive communication in the key agreement part of OT protocol. By these methods, we derive lower bounds on the OT capacity of BSC that are superior to the previous one for a certain range of crossover probabilities of the BSC. Via our new lower bound, we show that, at the crossover probability being zero, the slope of tangent of the OT capacity is unbounded.
format Preprint
id arxiv_https___arxiv_org_abs_2501_11883
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle An Improved Lower Bound on Oblivious Transfer Capacity Using Polarization and Interaction
Suda, So
Watanabe, Shun
Information Theory
We consider the oblivious transfer (OT) capacities of noisy channels against the passive adversary; this problem has not been solved even for the binary symmetric channel (BSC). In the literature, the general construction of OT has been known only for generalized erasure channels (GECs); for the BSC, we convert the channel to the binary symmetric erasure channel (BSEC), which is a special instance of the GEC, via alphabet extension and erasure emulation. In a previous paper by the authors, we derived an improved lower bound on the OT capacity of BSC by proposing a method to recursively emulate BSEC via interactive communication. In this paper, we introduce two new ideas of OT construction: (i) via ``polarization" and interactive communication, we recursively emulate GECs that are not necessarily a BSEC; (ii) in addition to the GEC emulation part, we also utilize interactive communication in the key agreement part of OT protocol. By these methods, we derive lower bounds on the OT capacity of BSC that are superior to the previous one for a certain range of crossover probabilities of the BSC. Via our new lower bound, we show that, at the crossover probability being zero, the slope of tangent of the OT capacity is unbounded.
title An Improved Lower Bound on Oblivious Transfer Capacity Using Polarization and Interaction
topic Information Theory
url https://arxiv.org/abs/2501.11883