The scope of ISO/TR 17427-4:2015 is, as an informative document, to identify potential critical minimum system requirements and behaviour for core systems issues that C-ITS service provision may face or introduce, to consider strategies for how to identify, control, limit or mitigate such issues. The objective of this Technical Report is to raise awareness of and consideration of such issues and to give pointers, where appropriate, to subject areas and, where available, to existing standards deliverables that provide specifications for all or some of these aspects. This Technical Report does not provide specifications for solutions of these issues.