# Physical Network **Entity class:** Network type A **physical network** represents connected material or engineered entities such as infrastructure, transportation systems, energy systems, sensors, communications hardware, facilities, or supply pathways. DTRA's basic-research record studies physical and social networks together because WMD acquisition, proliferation, use, and consequence can depend on interactions between human organization and material infrastructure. ## Relationships - **studied by:** [[wiki/Cognitive and Information Science|Cognitive and Information Science]]. - **contrasted with and coupled to:** [[wiki/Social Network Analysis|Social Network Analysis]]. - **represented within:** [[wiki/Multilayer Network|Multilayer Network]] and [[wiki/Threat Network|Threat Network]]. ## Sources - [Basic Research for Countering Weapons of Mass Destruction — DTRA](https://www.govinfo.gov/content/pkg/GOVPUB-D15-PURL-gpo18268/pdf/GOVPUB-D15-PURL-gpo18268.pdf) **As of:** 2026-09-23