http://www.rfc-editor.org/rfc/rfc7654.txt
RFC 7654: Benchmarking Methodology for In-Service Software Upgrade (ISSU), S. Banks, F. Calabria, G. Czirjak, R. Machat2015-10-01T23:00:00-00:00Modern forwarding devices attempt to minimize any control- and data-plane disruptions while performing planned software changes by implementing a technique commonly known as In-Service Software Upgrade (ISSU). This document specifies a set of common methodologies and procedures designed to characterize the overall behavior of a Device Under Test (DUT), subject to an ISSU event.