This document specifies a method for resolving IP addresses to ANSI High-Performance Parallel Interface (HIPPI) hardware addresses and for emulating IP broadcast in a logical IP subnet (LIS) as a direct extension of HARP (hardware addresses). This memo defines a HARP that will interoperate between HIPPI-800 and HIPPI-6400 (also known as Gigabyte System Network, GSN). This document (when combined with RFC 2067 "IP over HIPPI") obsoletes RFC 1374. [STANDARDS-TRACK]