# Current

Unless stated otherwise, the seminar takes place on Tuesdays,
from 10 to 11, in room 385 at IMB. To get announcements, you can subscribe to the

mailing-list.

2016-10-18

10:00

Salle 385

Gregor Seiler (ETH Zurich)

Computing ray class fields of imaginary quadratic fields

2016-11-22

10:00

Salle 385

Razvan Barbulescu

Pairings are a relatively new cryptographic tool which have been the
object of many arithmetic works. In the last few years some of the
pairings have become obsolete because of the progress on the underlying
problem of discrete logarithm in finite fields. We propose ourselves to
make a list of pairings constructions, to explain their advantages but
also their weaknesses. The sporadic curves are vulnerable to the Logjam
attack and have never been a popular choice. The small characteristic
curves allow a very good arithmetic but are the target of a
quasi-polynomial algorithm. The pairings where the characteristic has a
low Hamming weight, which eliminate the cost of modular reductions,
have been the object of special attacks. When the embedding degree is
composite the one can use the tower field arithmetic but there are also
tower field attacks.