In the context of WP3 “Work Package 3”, this deliverable D3.1describesthe use cases design, requirements specification, and technologies (software and hardware identification) related to the Infrastructure, Transportation, Security & Safety (ITSS) domain. Each use case includes details on its definition, application design, devices and equipment, infrastructures in support of their implementation, trials description, preliminary technical requirements, and the time plan. WP3 is responsible for all the activities towards the implementation of the use cases (UCs) in the ITSS domain for all the TrialsNet clusters and will address the main objectives of i) trial aset of innovative 6G applications and ii) to introduce societal benefits in different areas, thanks to 6G applications.