New potential user evaluating ArcGIS for possible telecommunications applications as a optical fiber routes, networks and rings with network analysts engine capable of correlating device alarms with fiber network layout.
Do they have a windows partition and a legitimate copy of Windows? If so, you can just download the trial version and follow the instructions beginning here...
To add to what Dan mentioned, review the ArcGIS Desktop 10.5 system requirements—ArcGIS Help | ArcGIS Desktop
You may also want to look into a free developer account and some of the App builder software that will allow you to create apps for ios and Internet browsers. The apps are more for collection vs analysis. But it may give you some ideas for the field collection, etc.
ArcGIS for Developers
Many of of these can be used with ArcGIS Online, and do not need Desktop software, so that may be away for you to get around OS limitations. There is some analysis available thru ArcGIS Online, but might not be everything you need...that is, not as fully functional as Desktop
ArcGIS Pro is also lacking all tools, but word is most tools will be ported from Desktop to Pro by the end of the year.
ArcGIS Pro | ArcGIS Desktop
Public or free trial accounts/licenses are available for all of the above, so you can test to see what will work before purchasing.
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