Even a pack of wild dogs will have a leaderthe alpha dog. The alpha dog serves as the leader of the pack and determines the pack's administrative pecking order. Although most network administrators do not resort to growling or the baring of fangs to maintain control on a network (although I know some who do), the network administrator is the alpha dog and determines all the conditions for user access to the network.
There are really two different aspects that an administrator deals with when working with network security and user access: user authentication and access permissions. User authentication is handled by assigning a user a logon name and a password. Other parameters, such as when a user can log on and whether a user can log on using a remote connection, are also configured by the administrator when he creates the user's account. We will discuss user accounts and different logon issues in a moment.
Access permission involves the level or the rights that an administrator assigns a user in relation to a particular resource on a network. For example, a user may have the ability to open and read files in a particular share on the network but not edit those files. We discussed the basics of network shares in Chapter 7, "Network Operating System Overview," and will discuss access permissions in more detail in this chapter after we spend some time sorting out user accounts.