It's treated the same as any other Windows VM (and thus depends on the product/edition and what channel you acquired the license from). In practical terms, the

It's treated the same as any other Windows VM (and thus depends on the product/edition and what channel you acquired the license from). In practical terms, the proper license would usually be a MSDN subscription; they're intended for development and testing, which is what Vagrant is mostly used for. (As an aside, the Technet ISOs have been discontinued for a while now; time-limited evaluation licenses are available instead.)