ASD ISM 0516Comprehensive Network Diagrams for Critical Components
Official control statement
Network documentation includes high-level network diagrams showing all connections into networks and logical network diagrams showing all critical servers, high-value servers, network devices and network security appliances.
Quoted as published. Everything else on this page is written by Control Stack.
In plain English
Create network diagrams showing connections, critical servers, and security devices for proper documentation.
What this means in practice
Creating network diagrams is like drawing a map of how your computers and important equipment are connected. This helps you see where security might be weak and ensures that all important devices are accounted for in case of an incident, preventing potential data breaches or system downtime.
Framework
ASD Information Security Manual (ISM)
Control effect (Control Stack)
Proactive
Classifications
NC, OS, P, S, TS
ISM last updated
Mar 2022
Control Stack last updated
29 Sept 2026
E8 maturity levels
N/A
Why it matters
Without up-to-date high-level and logical network diagrams, critical servers, devices and connections can be missed, delaying response and increasing breach risk.
Operational notes
Update high-level ingress/egress and logical diagrams after changes; include all critical/high-value servers, network devices and security appliances.
Implementation tips
- The IT team should create an initial high-level network diagram. Use simple drawing tools to map out how all the computers, servers, and security tools like firewalls are connected, showing the big picture in general terms.
- IT staff should update the logical network diagram regularly. Every time a new critical server or security device is added or removed, mark it on your detailed network map. This ensures the diagram remains accurate and useful.
- Managers should facilitate regular review meetings. Once every quarter, bring together IT staff and key stakeholders to go through the diagrams and identify any changes or risks. This helps maintain alignment across departments.
- Business owners should allocate resources for detailed network documentation. Encourage investing in tools or software that make diagramming easier and more comprehensive, improving clarity and accessibility.
- Managers should ensure secure storage of network diagrams. Print or save these diagrams in a secure but easily accessible format in a centralised location to protect the information while ensuring that it's available when needed.
Audit / evidence tips
- AskThe most recent network diagrams: Request both the high-level and detailed logical network diagramsLook atThe dates on the diagrams to ensure they're recentGoodIs diagrams updated within the last three months
- AskDocumentation of changes: Request records of updates or changes to the networkLook atEntries in a change log detailing what changes were made and whyGoodShows consistent updates reflecting recent network alterations
- AskHow diagrams are reviewed: Inquire about the process for regular diagram reviewsLook atEvidence of scheduled meetings or review processesGoodIncludes meeting minutes or notes demonstrating regular reviews
- AskAccess controls on diagrams: Request information about who can view and edit the network diagramsLook atPermission settings ensuring only authorised personnel have accessGoodIncludes a list of authorised users and their roles
- AskAbout storage solutions: Inquire where the diagrams are keptLook atThe storage system or location for security measures protecting this dataGoodInvolves secure digital storage with backup protocols in place
Cross-framework mappings
How ISM-0516 relates to controls across ISO/IEC 27001, ISO/IEC 42001, Essential Eight, and ASD ISM.
ISO 27001
| Control | Notes | Details |
|---|---|---|
layersPartially meets(1)expand_less | ||
| Annex A 8.20 | ISM-0516 requires organisations to maintain comprehensive network diagrams that show inbound/outbound connections and the placement of cr... | |
extensionDepends on(1)expand_less | ||
| Annex A 8.9 | ISM-0516 requires network documentation to include high-level and logical network diagrams showing all connections and all critical compo... | |
These mappings show relationships between controls across frameworks. They do not imply full equivalence or certification.
Related ASD ISM controls in Networking
See all Guidelines for networking controls, or browse the full ASD ISM library.