New Zealand Information Security Manual (NZISM) 19.4.5.C.01: EAL4 diode between NZEO and foreign networks

What does 19.4.5.C.01 require?

Agencies must place a diode evaluated to at least EAL4 at the boundary of an NZEO network with any foreign network, on top of the minimum diode assurance levels required where classifications differ.

Maintained by Gerard BlokdykVerified against the published standard 31 May 2026Control text last updated 21 May 2026

Other controls in Chapter 19: Gateway security – New Zealand Information Security Manual (NZISM)

19.1.10.C.01 19.1.10.C.01 Cascaded gateway chains meet end-to-end assurance levels
19.1.11.C.01 19.1.11.C.01 Gateways protect, filter and are physically secured
19.1.11.C.02 19.1.11.C.02 Shared gateway components managed by highest domain owner
19.1.12.C.01 19.1.12.C.01 Gateway configuration: sole path, default deny, isolated management
19.1.13.C.01 19.1.13.C.01 Operating gateways between different security domains
19.1.14.C.01 19.1.14.C.01 Use demilitarised zones for externally accessed systems
19.1.14.C.02 19.1.14.C.02 Host externally accessed systems in demilitarised zones
19.1.15.C.01 19.1.15.C.01 Risk assessment before gateway implementation

Query this from an agent

The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.

MCP endpoint All New Zealand Information Security Manual (NZISM) controls