address classes

address classes
   In a 32-bit IP address, which is shown in the accompanying illustration, the number of bits used to identify the network and the host vary according to the network class of the address, as follows:
   • Class A is used only for very large networks. The high-order bit in a Class A network is always zero, leaving 7 bits available to define 127 networks. The remaining 24 bits of the address allow each Class A network to hold as many as 16,777,216 hosts. Examples of Class A networks include General Electric, IBM, Hewlett-Packard, Apple Computer, Xerox, Digital Equipment Corporation, and MIT. All the Class A networks are in use, and no more are available.
   • Class B is used for medium-sized networks. The 2 high-order bits are always 10, and the remaining bits are used to define 16,384 networks, each with as many as 65,535 hosts attached. Examples of Class B networks include Microsoft and Exxon. All Class B networks are in use, and no more are available.
   • Class C is for smaller networks. The 3 high-order bits are always 110, and the remaining bits are used to define 2,097,152 networks, but each network can have a maximum of only 254 hosts. Class C networks are still available.
   • Class D is a special multicast address and cannot be used for networks. The 4 high• order bits are always 1110, and the remaining 28 bits allow for more than 268 million possible addresses.
   • Class E is reserved for experimental purposes. The first four bits in the address are always 1111.

Dictionary of networking . 2014.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • Address pool — An address pool is a set of IP addresses assigned by IANA or an organisation tied to it. These address pools are assigned primarily in three classes, enumerated A, B and C. A class A network is actually never assigned in practice; there are only… …   Wikipedia

  • IPv6 address — An Internet Protocol Version 6 address (IPv6 address) is a numerical label that is used to identify a network interface of a computer or other network node participating in an IPv6 enabled computer network. IP addresses serve the purpose of… …   Wikipedia

  • IPv4 address exhaustion — IP address exhaustion refers to the decreasing supply of unallocated IPv4 addresses. This depletion has been a concern since the 1980s when the Internet started to experience dramatic growth. As a result, this has been the driving factor in… …   Wikipedia

  • IP address —    The unique 32 bit number that identifies a computer on the Internet or some other Internet Protocol network. An IP address is usually written (in decimal) as four numbers separated by dots or periods and can be divided into two parts. The… …   Dictionary of networking

  • subnet address —    The subnet portion of an IP address. In a subnetted network, the host part of the IP address is divided into a subnet portion and a host portion by a subnet mask.    See also address classes; Classless Inter Domain Routing; IP address; subnet; …   Dictionary of networking

  • Andrew Jackson: Farewell Address — ▪ Primary Source              In his Farewell Address, written with the help of Chief Justice Roger B. Taney and delivered March 4, 1837, Andrew Jackson reviewed the accomplishments of his administration and explained the motivation of some of… …   Universalium

  • C++ classes — For background information, see C++. The C++ programming language allows programmers to separate program specific datatypes through the use of classes. Instances of these datatypes are known as objects and can contain member variables, constants …   Wikipedia

  • IP address — For the Wikipedia user access level, see Wikipedia:User access levels#Unregistered users. An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that… …   Wikipedia

  • IP address — Réseau privé Dans la nomenclature Internet, un réseau privé est un réseau qui utilise les plages d adressage définies par la RFC 1918 private IP address et qui n est pas relié à l Internet public. Un réseau privé peut être utilisé par n importe… …   Wikipédia en Français

  • Gettysburg Address — For the text of the Gettysburg Address, see Gettysburg Address at Wikisource. Main article: Consecration of the National Cemetery at Gettysburg The only confirmed photo of Abraham Lincoln (circled) at Gettysburg, taken about noon, just after… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”