Ultra-lightweight block cipher Twine

Twine is a 64-bit block cipher having 80-bit or 128-bit key. It employs the Generalized Feistel Structure (GFS), a scheme enabling a small footprint in hardware and software.
A cipher based on GFS usually incurs a slow speed due to the slow diffusion property. However, Twine uses an improved variant of GFS which significantly make diffusion faster (which was proposed at FSE 2010) and realizes a small and fast block cipher.
For example, Twine can be implemented in hardware using around 1/10 gates of a standard AES implementation.
The details of Twine and its security evaluation, implementations are described here.

Implementation results of Twine (for 80-bit key, encryption-only)

Hardware (ASIC)

Software implementation（Atmel AVR Atmega163）

Software implementation (Intel CPU, SSE)