The paper by Michael Scott “Missing a trick: Karatsuba variations” takes the reader for a tour through different versions of Karatsuba multiplication. This is of considerable interest for efficient implementations of public-key cryptography and in particular for Elliptic Curve Cryptography. The author discusses an interesting variant called “arbitrary-degree” Karatsuba (ADK).

In the paper “Backtracking-assisted multiplication”, Houda Ferradi, Remi G ´ eraud, Diana ´ Maimut, David Naccache and Hang Zhou describe a new multiplication algorithm, particularly suited to lightweight microprocessors. This leads to improvements when one of the operands is known in advance.