From: Tom Herbert <t...@herbertland.com> Date: Mon, 29 Apr 2019 16:15:11 -0700
> Extension headers are the mechanism of extensibility for the IPv6 > protocol, however to date they have only seen limited deployment. > The reasons for that are because intermediate devices don't handle > them well, and there haven't really be any useful extension headers > defined. In particular, Destination and Hop-by-Hop options have > not been deployed to any extent. > > The landscape may be changing as there are now a number of serious > efforts to define and deploy extension headers. In particular, a number > of uses for Hop-by-Hop Options are currently being proposed, Some of > these are from router vendors so there is hope that they might start > start to fix their brokenness. These proposals include IOAM, Path MTU, > Firewall and Service Tickets, SRv6, CRH, etc. > > Assuming that IPv6 extension headers gain traction, that leaves a > noticeable gap in IPv4 support. IPv4 options have long been considered a > non-starter for deployment. An alternative being proposed is to enable > use of IPv6 options with IPv4 (draft-herbert-ipv4-eh-00). "Assuming ipv6 extension headers gain traction, my patch set is useful." Well, when they gain traction you can propose this stuff. Until then, it's a facility implemented based upon wishful thinking. Sorry Tom, I kept pushing back using trivial coding style feedback because I simply can't justify applying this.
