Comparison of Authorization Models: NOS vs. Stand-alone OS

Old stand-alone operating systems typically used a local authorization model. This meant access rights were defined for users or groups directly on the machine itself. For example, if a user needed access to a file on a particular PC, their user account on that specific PC would need to be granted permission for that file. Permissions were tied to the local user database and applied only to resources on that single system.

Network Operating Systems (NOSs), in contrast, employ a centralized authorization model. Users and resources are managed across a network, not just on individual machines. Access rights are defined once, often in a central directory service (like Active Directory in Windows Server or LDAP in Linux environments), and then applied to shared resources accessible across the network. This allows for unified management of user accounts and permissions for resources such as shared folders, network printers, and applications on multiple servers. This is discussed in publications like Guide to Computer Network Security by Joseph Migga Kizza.