A resilient hashing system leverages a fast, non-cryptographic hash/checksum function that has good diffusion properties while remaining reasonably efficient on modern central processing units (CPUs). The hash function uses random secret data so that hash keys for particular data are difficult to predict. Due to its internal structure, well-chosen random secret data is difficult for an attacker to counter without having access to the direct output of the hash function. At every stage of the block function, there are at least two operations that can be performed in parallel, increasing performance on modern superscalar CPUs. Thus, the resilient hashing system provides a hash table and checksum that can be used in Internet-facing or other vulnerable sources of input data to manage performance in the face of malicious attacks.