Cybersecurity
Remote Access
Letting people in without leaving the door open.
Written guides in this section
Full references, procedures, and diagnostic guides published under Remote Access.
Vendor Remote Access
Integrators and equipment vendors need to get in. How to let them without leaving a permanent door open: utility-controlled sessions, named accounts, MFA, a jump host, session recording, and what to do about the modem you did not know was there.
11 min readUpdated Sep 5, 2026
VPN Design
How a VPN fits remote access for a control system: it terminates in the DMZ and lands on a jump host, never the control network; site-to-site tunnels carry telemetry; user tunnels require multi-factor and individual accounts; the concentrator is patched fast.
9 min readUpdated Sep 5, 2026
Jump Hosts
The one machine every remote session must pass through: what a jump host is, how it is hardened, what it may reach, session recording, the tools it carries, and why a vendor laptop never gets past it.
9 min readUpdated Sep 5, 2026
Multi-Factor Authentication
Requiring a second proof of identity beyond a password, where it matters most in a control system and how to do it without locking an operator out: the factor types, where it is mandatory, where it does not fit, enrollment and recovery, and vendor accounts.
8 min readUpdated Sep 5, 2026
Session Logging
Recording every remote session into the control system: who connected, from where, when, to what, and what they did, from the VPN log through jump host session recording to the SCADA audit trail and controller change log, stored off the systems and reviewed.
8 min readUpdated Sep 5, 2026
Topics in this area
Vendor Remote Access
Vendor Remote Access — practical reference notes for controls engineers, integrators, and technicians working with remote access.
VPN Design
VPN Design — practical reference notes for controls engineers, integrators, and technicians working with remote access.
Jump Hosts
Jump Hosts — practical reference notes for controls engineers, integrators, and technicians working with remote access.
Multi-Factor Authentication
Multi-Factor Authentication — practical reference notes for controls engineers, integrators, and technicians working with remote access.
Session Logging
Session Logging — practical reference notes for controls engineers, integrators, and technicians working with remote access.
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