Adam Sampson's icmp bookmarkshttps://bookmarks.offog.org/ats/icmpAdam Sampson2016-10-14T16:18:00ZSamy Kamkar - pwnat: NAT to NAT client-server communicationhttps://bookmarks.offog.org/edit?url=http%3A%2F%2Fsamy.pl%2Fpwnat%2F2016-10-14T16:18:00ZHole-punching by forged ICMP. Neat, and the paper does have some description of how well it works in practice.