api: nitfix(off by 1) & readability/documentation
api: nitfix(off by 1) & readability/documentation

protocol O(1) checking now documents length-expectations (and
technically gets newly-changed request protocol slightly better).

jzacsh/netwtcpip-cmp405,jzacsh/netwtcpip-cmp405,jzacsh/netwtcpip-cmp405,jzacsh/netwtcpip-cmp405