Nothing, whether inside or outside the network perimeter of an organisation, must automatically be trusted. Therefore, anyone and anything trying to connect to an organisation's system must be verified before being granted access. The main objective of this approach is to mitigate the risk of cyber-attacks in the modern environments that are the theatre of activity for most organisations.
Access to any of your company's resources must therefore be protected by a login system, which will allow you not only to prevent unwanted access, but also to be able to perform any access controls on the various resources.