Its NUMBER@1 rounds are arranged as a source-heavy Feistel network , with NUMBER@2 rounds of one type -LRB- MIXING -RRB- punctuated by two rounds of another type -LRB- MASHING -RRB- .

Rounds are arranged as a source-heavy feistel network , with NUMBER@2 rounds of one type called `` mixing rounds '' interleaved by two rounds of another type called `` mashing rounds '' .
