The amount of trust required (and thus operational, physical, personnel, network, and system security applied) is commensurate with the risk of piracy, tampering, and reverse engineering (within a given threat environment).
A Secure End Node typically involves authentication of (i.e. establishing trust in) the remote computer's hardware, firmware, software, and/or user.
The common, but expensive, technique to deploy SENs is for the network owner to issue known, trusted, unchangeable hardware to users.
[1] A less secure but very low cost approach is to trust any hardware (corporate, government, personal, or public) but restrict user and network access to a known kernel (computing) and higher software.
An implementation of this is a Linux Live CD that creates a stateless, non-persistent client, for example Lightweight Portable Security.