Idea NXT

FOX, also referred to as IDEA NXT, is a symmetric encryption algorithm, which was co-developed by Serge Vaudenay and Pascal Junod. He represents the successor of the IDEA and was published in 2003.

FOX is a block cipher with a block size of 64 or 128 bits. It works with key lengths of 128 or 256 bits. FOX is a very fast but patented algorithm. However, there are legal doubt whether patent protection in the European Union at all valid.