I want to generate a small 30 or 32 bit PRP. I am going to use that PRP in an open web service and anyone will be able to get any number of plaintext-cyphertext pairs.
I've found an algorithm called FastPRP and the problem statement fits my requirements perfectly. However the performance seems quite low for 30-32 bit range. I need a high-performant point evaluations for both PRP and an inverse PRP.
Are there any 32-bit PRP algorithms (less secure probably) that allow a faster point evaluations?