Name
Abstract | ||
|---|---|---|
In this paper, we propose secret-sharing-based bit-decomposition and modulus-conversion protocols for a prime order ring Z(p) with an honest majority: an adversary can corrupt k - 1 parties of n parties and 2k - 1 <= n. Our protocols are secure against passive and active adversaries depending on the components of our protocols. We assume a secret is an l-bit element and 2(l+inverted right perpendicular log m )(inverted left perpendicular) < p, where m = k in the passive security and m ((n)(k-1)) in the active security. The outputs of our bit-decomposition and modulus-conversion protocols are tuple of shares in Z(2) and a share Z(p'), in respectively, where p' is the modulus after the conversion. If k and n are small, the communication complexity of our passively secure bit-decomposition and modulus-conversion protocols are O(l) bits and O (inverted right perpendicular log p' inverted left perpendicular) bits, respectively. Our key observation is that a quotient of additive shares can be computed from the least significant inverted right perpendicular log m( )inverted left perpendicular bits. If a secret a is "shifted" and additively shared as x(i)s so that 2(inverted right perpendicular log m) (inverted left perpendicular) a = Sigma(m-1)(i=0) x(i) = 2(inverted right perpendicular log m) (inverted left perpendicular) a + qp, the least significant Flog ml bits of Sigma(m-1)(i=0) determine q since p is an odd prime and the least significant inverted (right perpendicular log m) (inverted left perpendicular) bits of 2(inverted right perpendicular log m) (inverted left perpendicular) a are 0s. |
Year | DOI | Venue |
|---|---|---|
2018 | 10.1007/978-3-319-93638-3_5 | INFORMATION SECURITY AND PRIVACY |
Keywords | DocType | Volume |
Bit decomposition, Modulus conversion, Secure computation, Secret sharing, Honest majority | Conference | 10946 |
ISSN | Citations | PageRank |
0302-9743 | 0 | 0.34 |
References | Authors | |
13 | 5 | |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Ryo Kikuchi | 1 | 46 | 9.37 |
| Dai Ikarashi | 2 | 27 | 6.33 |
| Takahiro Matsuda | 3 | 343 | 42.05 |
| Koki Hamada | 4 | 61 | 10.92 |
| Koji Chida | 5 | 73 | 12.49 |