The Network Information Service, or NIS (originally called Yellow Pages or YP), is a
client–server directory service
In computing, a directory service or name service maps the names of network resources to their respective network addresses. It is a shared information infrastructure for locating, managing, administering and organizing everyday items and network ...
protocol for
distributing system configuration data such as
user and
host name
In computer networking, a hostname (archaically nodename) is a label that is assigned to a device connected to a computer network and that is used to identify the device in various forms of electronic communication, such as the World Wide Web. Hos ...
s between
computers on a
computer network
A computer network is a set of computers sharing resources located on or provided by network nodes. The computers use common communication protocols over digital interconnections to communicate with each other. These interconnections ar ...
.
Sun Microsystems
Sun Microsystems, Inc. (Sun for short) was an American technology company that sold computers, computer components, software, and information technology services and created the Java programming language, the Solaris operating system, ZFS, ...
developed the NIS; the technology is
licensed to virtually all other
Unix
Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...
vendors.
Because
British Telecom
BT Group plc (trade name, trading as BT and formerly British Telecom) is a British Multinational corporation, multinational telecommunications holding company headquartered in London, England. It has operations in around 180 countries and is th ...
PLC owned the name "
Yellow Pages
The yellow pages are telephone directories of businesses, organized by category rather than alphabetically by business name, in which advertising is sold. The directories were originally printed on yellow paper, as opposed to Telephone direct ...
" as a registered
trademark
A trademark (also written trade mark or trade-mark) is a type of intellectual property consisting of a recognizable sign, design, or expression that identifies products or services from a particular source and distinguishes them from oth ...
in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...
for its paper-based, commercial
telephone directory
A telephone directory, commonly called a telephone book, telephone address book, phonebook, or the white and yellow pages, is a listing of telephone subscribers in a geographical area or subscribers to services provided by the organization that ...
, Sun changed the name of its system to NIS, though all the commands and functions still start with "yp".
A NIS/YP system maintains and distributes a central directory of user and group information, hostnames, e-mail aliases and other text-based tables of information in a computer network. For example, in a common
UNIX
Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...
environment, the list of users for
identification
Identification or identify may refer to:
*Identity document, any document used to verify a person's identity
Arts, entertainment and media
* ''Identify'' (album) by Got7, 2014
* "Identify" (song), by Natalie Imbruglia, 1999
*Identification (a ...
is placed in and secret
authentication
Authentication (from ''authentikos'', "real, genuine", from αὐθέντης ''authentes'', "author") is the act of proving an assertion, such as the identity of a computer system user. In contrast with identification, the act of indicat ...
hashes in . NIS adds another "global" user list which is used for identifying users on any
client
Client(s) or The Client may refer to:
* Client (business)
* Client (computing), hardware or software that accesses a remote service on another computer
* Customer or client, a recipient of goods or services in return for monetary or other valuabl ...
of the NIS domain.
Administrators have the ability to configure NIS to serve password data to outside processes to authenticate users using various versions of the Unix
crypt(3) hash algorithms. However, in such cases, any NIS(0307) client can retrieve the entire password database for offline inspection.
Successor technologies
The original NIS design was seen to have inherent limitations, especially in the areas of scalability and security, so other technologies have come to replace it.
Sun introduced
NIS+ as part of
Solaris 2 in 1992, with the intention for it to eventually supersede NIS. NIS+ features much stronger security and authentication features, as well as a hierarchical design intended to provide greater scalability and flexibility. However, it was also more cumbersome to set up and administer, and was more difficult to integrate into an existing NIS environment than many existing users wished.
NIS+ has been removed from Solaris 11.
As a result, many users choose to stick with NIS, and over time other modern and secure distributed directory systems, most notably
Lightweight Directory Access Protocol (LDAP), came to replace it. For example,
slapd
(the standalone LDAP
daemon) generally runs as a non-
root user
In computing, the superuser is a special user account used for system administration. Depending on the operating system (OS), the actual name of this account might be root, administrator, admin or supervisor. In some cases, the actual name of t ...
, and
SASL-based encryption of LDAP traffic is natively supported.
On large
LAN
Lan or LAN may also refer to:
Science and technology
* Local asymptotic normality, a fundamental property of regular models in statistics
* Longitude of the ascending node, one of the orbital elements used to specify the orbit of an object in sp ...
s,
DNS
The Domain Name System (DNS) is a hierarchical and distributed naming system for computers, services, and other resources in the Internet or other Internet Protocol (IP) networks. It associates various information with domain names assigned to ...
servers may provide better
nameserver
A name server refers to the server component of the Domain Name System (DNS), one of the two principal namespaces of the Internet. The most important function of DNS servers is the translation (resolution) of human-memorable domain names (example ...
functionality than NIS or LDAP can provide, leaving just site-wide identification information for NIS master and slave systems to serve. However, some functionssuch as the distribution of netmask information to clients, as well as the maintenance of e-mail aliasesmay still be performed by NIS or LDAP. NIS maintains an
NFS database information file as well as so called maps.
See also
*
Dynamic Host Configuration Protocol
The Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on Internet Protocol (IP) networks for automatically assigning IP addresses and other communication parameters to devices connected to the network using a cli ...
(DHCP)
*
Hesiod (name service)
*
Name Service Switch (NSS)
*
Network information system, for a broader use of NIS to manage other system and networks
References
External links
*
*
*
*
*
* RHEL 9 will remove support for NI
Alexander Bokovoy, Sr. Principal Software Engineer slide show
{{Sun Microsystems
Unix network-related software
Sun Microsystems software
Network management
Directory services
Inter-process communication