// TAG · HANS STUDY POSTS
#network-security
6 posts tagged #network-security.
Hardening HPE Aruba CX Switches Running AOS-CX: A Practical Baseline
A hardening baseline for HPE Aruba CX access and distribution switches on AOS-CX: SSH on the management VRF, AAA, SNMPv3, authenticated NTP, DHCP snooping, ARP ...
Hardening Cisco Catalyst Switches Running IOS-XE: A Practical Baseline
A working hardening baseline for Cisco Catalyst access and distribution switches on IOS-XE, from SSH-only management and SNMPv3 to DHCP snooping, DAI, and a bla...
IEC 62443 Zones and Conduits for a Small Plant, Worked Through
A worked IEC 62443 zones and conduits example for one small site with 3 PLCs, an HMI, a historian, an engineering workstation, and a vendor remote link, with th...
Security Controls for OT Networks That Hold Up in Production
The security controls an operational technology network actually needs, applied in a way that respects how plant systems run. Zones and conduits, the iDMZ, prot...
The Firewall Did Its Job: What FortiBleed Was Really About
FortiBleed wasn't a firewall flaw. It was a pile of reused, never-rotated credentials with a brand name attached. The lesson is older than the headline....
Nobody Owns the Network Between the Integrator and IT
When physical security systems sit on critical infrastructure networks, the most dangerous gap isn't technical. It's that no one is responsible for the seam bet...