Resilient connections for SSH and TLS

Abstract

Disconnection of an SSH shell or a secure application session due to network outages or travel is a familiar problem to many Internet users today. In this paper, we extend the SSH and TLS protocols to support re-silient connections that can span several sequential TCP connections. The extensions allow sessions to survive both changes in IP addresses and long periods of discon-nection. Our design emphasizes deployability in real-world environments, and addresses many of the chal-lenges identified in previous work, including assump-tions made about network middleboxes such as firewalls and NATs. We have also implemented the extensions in the OpenSSH and PureTLS software packages and tested them in practice. 1