Building Internet Firewalls, 2nd Edition

Chapter 20. Naming and Directory Services

This chapter discusses services used to distribute information about machines, people and network addresses. This includes naming services, which translate hostnames to IP addresses (and vice versa) and more general directory services. The Internet standard for name service is the Domain Name System (DNS), but other protocols, including the Network Information Service (NIS) and the Windows Internet Name Service (WINS), are used to distribute this information within individual networks. In addition, this chapter discusses the Windows Browser, which is also used by human beings to find machines; the Lightweight Directory Access Protocol (LDAP), which is used for a wide range of directory information; the finger program, which provides information about people; and the whois program, which provides information about network ownership.

Domain Name System (DNS)

The Domain Name System (DNS) is an Internet-wide system for the resolution of hostnames and IP addresses. You will also see it called Domain Name Service. Unfortunately for the sanity of administrators, the Domain Name System and Microsoft Windows domains are different things. Microsoft Windows machines can and do use DNS (and it is required for Windows 2000), but a Windows domain is fundamentally a unit of authority that may or may not control the name of a machine. (Windows domains are discussed further in Chapter 21 ; they are also relevant to the Browser, which is discussed later in ...