# When A Sponge Helps To Make Things Secure — And Light-weight

When can you get a hash function and also implement encryption? Well, you can when you have a sponge, and which stores and processes a permutation value. It was first introduced with SHA-3 and where we define a state size (S) of 1600 bits (Keccak-f[1600]). This state (S) is made up from r (rate) and c (capacity). The total bits in the state is thus 1,600 bits. With this we can either…