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ISPs) began to emerge in the late 1980s and early 1990s. The
ARPANET was decommissioned
in 1990. The Internet was commercialized in 1995 when NSFNET was
decommissioned,
removing the last restrictions on the use of the Internet to
carry commercial traffic.[19]
TheInternet started a rapid expansion to Europe and Australia in
the mid to late 1980s
[20][21]and to
Asia in the late 1980s and early 1990s.[22]
ThisNeXT Computerwas used bySir Tim Berners-LeeatCERNand became
the world's firstWeb server.
Since the mid-1990s the Internet has had a tremendous impact on
culture and commerce,including the rise of near instant
communication by email,instant messaging,Voice overInternet
Protocol(VoIP) "phone calls",two-way interactive video calls, and
theWorld Wide
Web[23]
with itsdiscussion forums, blogs,social networking, andonline
shoppingsites.
Increasing amounts of data are transmitted at higher and higher
speeds over fiber optic networksoperating at 1-Gbit/s, 10-Gbit/s,
or more. The Internet continues to grow, driven by ever greater
amounts of online information and knowledge, commerce,
entertainment andsocial
networking.[24]
During the late 1990s, it was estimated that traffic on the
public Internet grew by 100 percent per
year, while the mean annual growth in the number of Internet
users was thought to be between
20% and 50%.[25]
This growth is often attributed to the lack of central
administration, whichallows organic growth of the network, as well
as the non-proprietary open nature of the Internet
protocols, which encourages vendor interoperability and prevents
any one company from
exerting too much control over the network.[26]
As of 31 March 2011, the estimated total numberofInternet
userswas 2.095 billion (30.2% of world population).
[27]It is estimated that in 1993
the Internet carried only 1% of the information flowing through
two-way telecommunication, by
2000 this figure had grown to 51%, and by 2007 more than 97% of
all telecommunicated
information was carried over the Internet.[28]
Technology
Protocols
Main article:Internet protocol suite
http://en.wikipedia.org/wiki/Internet#cite_note-ConneXions-April1996-19http://en.wikipedia.org/wiki/Internet#cite_note-ConneXions-April1996-19http://en.wikipedia.org/wiki/Internet#cite_note-ConneXions-April1996-19http://en.wikipedia.org/wiki/Internet#cite_note-20http://en.wikipedia.org/wiki/Internet#cite_note-20http://en.wikipedia.org/wiki/Internet#cite_note-20http://en.wikipedia.org/wiki/Internet#cite_note-22http://en.wikipedia.org/wiki/Internet#cite_note-22http://en.wikipedia.org/wiki/Internet#cite_note-22http://en.wikipedia.org/wiki/NeXT_Computerhttp://en.wikipedia.org/wiki/NeXT_Computerhttp://en.wikipedia.org/wiki/NeXT_Computerhttp://en.wikipedia.org/wiki/Sir_Tim_Berners-Leehttp://en.wikipedia.org/wiki/Sir_Tim_Berners-Leehttp://en.wikipedia.org/wiki/Sir_Tim_Berners-Leehttp://en.wikipedia.org/wiki/CERNhttp://en.wikipedia.org/wiki/CERNhttp://en.wikipedia.org/wiki/CERNhttp://en.wikipedia.org/wiki/Web_serverhttp://en.wikipedia.org/wiki/Web_serverhttp://en.wikipedia.org/wiki/Instant_messaginghttp://en.wikipedia.org/wiki/Instant_messaginghttp://en.wikipedia.org/wiki/Instant_messaginghttp://en.wikipedia.org/wiki/Voice_over_Internet_Protocolhttp://en.wikipedia.org/wiki/Voice_over_Internet_Protocolhttp://en.wikipedia.org/wiki/Voice_over_Internet_Protocolhttp://en.wikipedia.org/wiki/Voice_over_Internet_Protocolhttp://en.wikipedia.org/wiki/Video_chathttp://en.wikipedia.org/wiki/Video_chathttp://en.wikipedia.org/wiki/Video_chathttp://en.wikipedia.org/wiki/World_Wide_Webhttp://en.wikipedia.org/wiki/World_Wide_Webhttp://en.wikipedia.org/wiki/World_Wide_Webhttp://en.wikipedia.org/wiki/Internet#cite_note-23http://en.wikipedia.org/wiki/Internet#cite_note-23http://en.wikipedia.org/wiki/Discussion_forumshttp://en.wikipedia.org/wiki/Discussion_forumshttp://en.wikipedia.org/wiki/Discussion_forumshttp://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Online_shoppinghttp://en.wikipedia.org/wiki/Online_shoppinghttp://en.wikipedia.org/wiki/Online_shoppinghttp://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Internet#cite_note-24http://en.wikipedia.org/wiki/Internet#cite_note-24http://en.wikipedia.org/wiki/Internet#cite_note-24http://en.wikipedia.org/wiki/Internet#cite_note-25http://en.wikipedia.org/wiki/Internet#cite_note-25http://en.wikipedia.org/wiki/Internet#cite_note-25http://en.wikipedia.org/wiki/Internet#cite_note-26http://en.wikipedia.org/wiki/Internet#cite_note-26http://en.wikipedia.org/wiki/Internet#cite_note-26http://en.wikipedia.org/wiki/Internet_usershttp://en.wikipedia.org/wiki/Internet_usershttp://en.wikipedia.org/wiki/Internet_usershttp://en.wikipedia.org/wiki/Internet#cite_note-stats1-27http://en.wikipedia.org/wiki/Internet#cite_note-stats1-27http://en.wikipedia.org/wiki/Internet#cite_note-stats1-27http://en.wikipedia.org/wiki/Internet#cite_note-28http://en.wikipedia.org/wiki/Internet#cite_note-28http://en.wikipedia.org/wiki/Internet#cite_note-28http://en.wikipedia.org/wiki/Internet_protocol_suitehttp://en.wikipedia.org/wiki/Internet_protocol_suitehttp://en.wikipedia.org/wiki/Internet_protocol_suitehttp://en.wikipedia.org/wiki/File:First_Web_Server.jpghttp://en.wikipedia.org/wiki/File:First_Web_Server.jpghttp://en.wikipedia.org/wiki/File:First_Web_Server.jpghttp://en.wikipedia.org/wiki/File:First_Web_Server.jpghttp://en.wikipedia.org/wiki/Internet_protocol_suitehttp://en.wikipedia.org/wiki/Internet#cite_note-28http://en.wikipedia.org/wiki/Internet#cite_note-stats1-27http://en.wikipedia.org/wiki/Internet_usershttp://en.wikipedia.org/wiki/Internet#cite_note-26http://en.wikipedia.org/wiki/Internet#cite_note-25http://en.wikipedia.org/wiki/Internet#cite_note-24http://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Online_shoppinghttp://en.wikipedia.org/wiki/Social_networkinghttp://en.wikipedia.org/wiki/Discussion_forumshttp://en.wikipedia.org/wiki/Internet#cite_note-23http://en.wikipedia.org/wiki/World_Wide_Webhttp://en.wikipedia.org/wiki/World_Wide_Webhttp://en.wikipedia.org/wiki/Video_chathttp://en.wikipedia.org/wiki/Voice_over_Internet_Protocolhttp://en.wikipedia.org/wiki/Voice_over_Internet_Protocolhttp://en.wikipedia.org/wiki/Instant_messaginghttp://en.wikipedia.org/wiki/Web_serverhttp://en.wikipedia.org/wiki/CERNhttp://en.wikipedia.org/wiki/Sir_Tim_Berners-Leehttp://en.wikipedia.org/wiki/NeXT_Computerhttp://en.wikipedia.org/wiki/Internet#cite_note-22http://en.wikipedia.org/wiki/Internet#cite_note-20http://en.wikipedia.org/wiki/Internet#cite_note-20http://en.wikipedia.org/wiki/Internet#cite_note-ConneXions-April1996-19
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As the user data is processed down through the protocol stack,
each layer adds an encapsulation
at the sending host. Data is transmitted "over the wire" at the
link level, left to right. The
encapsulation stack procedure is reversed by the receiving host.
Intermediate relays remove andadd a new link encapsulation for
retransmission, and inspect the IP layer for routing purposes.
Internet protocol suite
Application layer
DHCP DHCPv6 DNS FTP HTTP
IMAP IRC
LDAP MGCP NNTP BGP NTP POP RPC
RTP RTSP RIP SIP
SMTP SNMP
http://en.wikipedia.org/wiki/Internet_protocol_suitehttp://en.wikipedia.org/wiki/Application_layerhttp://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocolhttp://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocolhttp://en.wikipedia.org/wiki/DHCPv6http://en.wikipedia.org/wiki/DHCPv6http://en.wikipedia.org/wiki/Domain_Name_Systemhttp://en.wikipedia.org/wiki/Domain_Name_Systemhttp://en.wikipedia.org/wiki/File_Transfer_Protocolhttp://en.wikipedia.org/wiki/File_Transfer_Protocolhttp://en.wikipedia.org/wiki/Hypertext_Transfer_Protocolhttp://en.wikipedia.org/wiki/Hypertext_Transfer_Protocolhttp://en.wikipedia.org/wiki/Internet_Message_Access_Protocolhttp://en.wikipedia.org/wiki/Internet_Message_Access_Protocolhttp://en.wikipedia.org/wiki/Internet_Relay_Chathttp://en.wikipedia.org/wiki/Internet_Relay_Chathttp://en.wikipedia.org/wiki/Lightweight_Directory_Access_Protocolhttp://en.wikipedia.org/wiki/Lightweight_Directory_Access_Protocolhttp://en.wikipedia.org/wiki/Media_Gateway_Control_Protocolhttp://en.wikipedia.org/wiki/Media_Gateway_Control_Protocolhttp://en.wikipedia.org/wiki/Network_News_Transfer_Protocolhttp://en.wikipedia.org/wiki/Network_News_Transfer_Protocolhttp://en.wikipedia.org/wiki/Border_Gateway_Protocolhttp://en.wikipedia.org/wiki/Border_Gateway_Protocolhttp://en.wikipedia.org/wiki/Network_Time_Protocolhttp://en.wikipedia.org/wiki/Network_Time_Protocolhttp://en.wikipedia.org/wiki/Post_Office_Protocolhttp://en.wikipedia.org/wiki/Post_Office_Protocolhttp://en.wikipedia.org/wiki/Remote_procedure_callhttp://en.wikipedia.org/wiki/Remote_procedure_callhttp://en.wikipedia.org/wiki/Real-time_Transport_Protocolhttp://en.wikipedia.org/wiki/Real-time_Transport_Protocolhttp://en.wikipedia.org/wiki/Real_Time_Streaming_Protocolhttp://en.wikipedia.org/wiki/Real_Time_Streaming_Protocolhttp://en.wikipedia.org/wiki/Routing_Information_Protocolhttp://en.wikipedia.org/wiki/Routing_Information_Protocolhttp://en.wikipedia.org/wiki/Session_Initiation_Protocolhttp://en.wikipedia.org/wiki/Session_Initiation_Protocolhttp://en.wikipedia.org/wiki/Simple_Mail_Transfer_Protocolhttp://en.wikipedia.org/wiki/Simple_Mail_Transfer_Protocolhttp://en.wikipedia.org/wiki/Simple_Network_Management_Protocolhttp://en.wikipedia.org/wiki/Simple_Network_Management_Protocolhttp://en.wikipedia.org/wiki/File:UDP_encapsulation.svghttp://en.wikipedia.org/wiki/File:UDP_encapsulation.svghttp://en.wikipedia.org/wiki/File:UDP_encapsulation.svghttp://en.wikipedia.org/wiki/File:UDP_encapsulation.svghttp://en.wikipedia.org/wiki/Simple_Network_Management_Protocolhttp://en.wikipedia.org/wiki/Simple_Mail_Transfer_Protocolhttp://en.wikipedia.org/wiki/Session_Initiation_Protocolhttp://en.wikipedia.org/wiki/Routing_Information_Protocolhttp://en.wikipedia.org/wiki/Real_Time_Streaming_Protocolhttp://en.wikipedia.org/wiki/Real-time_Transport_Protocolhttp://en.wikipedia.org/wiki/Remote_procedure_callhttp://en.wikipedia.org/wiki/Post_Office_Protocolhttp://en.wikipedia.org/wiki/Network_Time_Protocolhttp://en.wikipedia.org/wiki/Border_Gateway_Protocolhttp://en.wikipedia.org/wiki/Network_News_Transfer_Protocolhttp://en.wikipedia.org/wiki/Media_Gateway_Control_Protocolhttp://en.wikipedia.org/wiki/Lightweight_Directory_Access_Protocolhttp://en.wikipedia.org/wiki/Internet_Relay_Chathttp://en.wikipedia.org/wiki/Internet_Message_Access_Protocolhttp://en.wikipedia.org/wiki/Hypertext_Transfer_Protocolhttp://en.wikipedia.org/wiki/File_Transfer_Protocolhttp://en.wikipedia.org/wiki/Domain_Name_Systemhttp://en.wikipedia.org/wiki/DHCPv6http://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocolhttp://en.wikipedia.org/wiki/Application_layerhttp://en.wikipedia.org/wiki/Internet_protocol_suite
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SOCKS SSH Telnet
TLS/SSL XMPP (more)
Transport layer
TCP UDP DCCP SCTP RSVP (more)
Internet layer
IPo IPv4o IPv6
OSPF ICMP
ICMPv6 ECN IGMP IPsec (more)
Link layer
ARP/InARP NDP
Tunnelso L2TP
PPP Media access control
o Ethernet
http://en.wikipedia.org/wiki/SOCKShttp://en.wikipedia.org/wiki/SOCKShttp://en.wikipedia.org/wiki/Secure_Shellhttp://en.wikipedia.org/wiki/Secure_Shellhttp://en.wikipedia.org/wiki/Telnethttp://en.wikipedia.org/wiki/Telnethttp://en.wikipedia.org/wiki/Transport_Layer_Securityhttp://en.wikipedia.org/wiki/Transport_Layer_Securityhttp://en.wikipedia.org/wiki/XMPPhttp://en.wikipedia.org/wiki/XMPPhttp://en.wikipedia.org/wiki/Category:Application_layer_protocolshttp://en.wikipedia.org/wiki/Category:Application_layer_protocolshttp://en.wikipedia.org/wiki/Transport_layerhttp://en.wikipedia.org/wiki/Transmission_Control_Protocolhttp://en.wikipedia.org/wiki/Transmission_Control_Protocolhttp://en.wikipedia.org/wiki/User_Datagram_Protocolhttp://en.wikipedia.org/wiki/User_Datagram_Protocolhttp://en.wikipedia.org/wiki/Datagram_Congestion_Control_Protocolhttp://en.wikipedia.org/wiki/Datagram_Congestion_Control_Protocolhttp://en.wikipedia.org/wiki/Stream_Control_Transmission_Protocolhttp://en.wikipedia.org/wiki/Stream_Control_Transmission_Protocolhttp://en.wikipedia.org/wiki/Resource_Reservation_Protocolhttp://en.wikipedia.org/wiki/Resource_Reservation_Protocolhttp://en.wikipedia.org/wiki/Category:Transport_layer_protocolshttp://en.wikipedia.org/wiki/Category:Transport_layer_protocolshttp://en.wikipedia.org/wiki/Internet_layerhttp://en.wikipedia.org/wiki/Internet_Protocolhttp://en.wikipedia.org/wiki/Internet_Protocolhttp://en.wikipedia.org/wiki/IPv4http://en.wikipedia.org/wiki/IPv4http://en.wikipedia.org/wiki/IPv6http://en.wikipedia.org/wiki/IPv6http://en.wikipedia.org/wiki/Open_Shortest_Path_Firsthttp://en.wikipedia.org/wiki/Open_Shortest_Path_Firsthttp://en.wikipedia.org/wiki/Internet_Control_Message_Protocolhttp://en.wikipedia.org/wiki/Internet_Control_Message_Protocolhttp://en.wikipedia.org/wiki/ICMPv6http://en.wikipedia.org/wiki/ICMPv6http://en.wikipedia.org/wiki/Explicit_Congestion_Notificationhttp://en.wikipedia.org/wiki/Explicit_Congestion_Notificationhttp://en.wikipedia.org/wiki/Internet_Group_Management_Protocolhttp://en.wikipedia.org/wiki/Internet_Group_Management_Protocolhttp://en.wikipedia.org/wiki/IPsechttp://en.wikipedia.org/wiki/IPsechttp://en.wikipedia.org/wiki/Category:Internet_layer_protocolshttp://en.wikipedia.org/wiki/Category:Internet_layer_protocolshttp://en.wikipedia.org/wiki/Link_layerhttp://en.wikipedia.org/wiki/Link_layerhttp://en.wikipedia.org/wiki/Address_Resolution_Protocolhttp://en.wikipedia.org/wiki/Address_Resolution_Protocolhttp://en.wikipedia.org/wiki/Neighbor_Discovery_Protocolhttp://en.wikipedia.org/wiki/Neighbor_Discovery_Protocolhttp://en.wikipedia.org/wiki/Tunneling_protocolhttp://en.wikipedia.org/wiki/Tunneling_protocolhttp://en.wikipedia.org/wiki/Layer_2_Tunneling_Protocolhttp://en.wikipedia.org/wiki/Layer_2_Tunneling_Protocolhttp://en.wikipedia.org/wiki/Point-to-point_protocolhttp://en.wikipedia.org/wiki/Point-to-point_protocolhttp://en.wikipedia.org/wiki/Media_access_controlhttp://en.wikipedia.org/wiki/Media_access_controlhttp://en.wikipedia.org/wiki/Ethernethttp://en.wikipedia.org/wiki/Ethernethttp://en.wikipedia.org/wiki/Ethernethttp://en.wikipedia.org/wiki/Media_access_controlhttp://en.wikipedia.org/wiki/Point-to-point_protocolhttp://en.wikipedia.org/wiki/Layer_2_Tunneling_Protocolhttp://en.wikipedia.org/wiki/Tunneling_protocolhttp://en.wikipedia.org/wiki/Neighbor_Discovery_Protocolhttp://en.wikipedia.org/wiki/Address_Resolution_Protocolhttp://en.wikipedia.org/wiki/Link_layerhttp://en.wikipedia.org/wiki/Category:Internet_layer_protocolshttp://en.wikipedia.org/wiki/IPsechttp://en.wikipedia.org/wiki/Internet_Group_Management_Protocolhttp://en.wikipedia.org/wiki/Explicit_Congestion_Notificationhttp://en.wikipedia.org/wiki/ICMPv6http://en.wikipedia.org/wiki/Internet_Control_Message_Protocolhttp://en.wikipedia.org/wiki/Open_Shortest_Path_Firsthttp://en.wikipedia.org/wiki/IPv6http://en.wikipedia.org/wiki/IPv4http://en.wikipedia.org/wiki/Internet_Protocolhttp://en.wikipedia.org/wiki/Internet_layerhttp://en.wikipedia.org/wiki/Category:Transport_layer_protocolshttp://en.wikipedia.org/wiki/Resource_Reservation_Protocolhttp://en.wikipedia.org/wiki/Stream_Control_Transmission_Protocolhttp://en.wikipedia.org/wiki/Datagram_Congestion_Control_Protocolhttp://en.wikipedia.org/wiki/User_Datagram_Protocolhttp://en.wikipedia.org/wiki/Transmission_Control_Protocolhttp://en.wikipedia.org/wiki/Transport_layerhttp://en.wikipedia.org/wiki/Category:Application_layer_protocolshttp://en.wikipedia.org/wiki/XMPPhttp://en.wikipedia.org/wiki/Transport_Layer_Securityhttp://en.wikipedia.org/wiki/Telnethttp://en.wikipedia.org/wiki/Secure_Shellhttp://en.wikipedia.org/wiki/SOCKS
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o DSLo ISDNo FDDI
(more)
v t e
The communications infrastructure of the Internet consists of
its hardware components and a
system of software layers that control various aspects of the
architecture. While the hardware can
often be used to support other software systems, it is the
design and the rigorous standardization
process of the software architecture that characterizes the
Internet and provides the foundationfor its scalability and
success. The responsibility for the architectural design of the
Internet
software systems has been delegated to theInternet Engineering
Task Force(IETF).[29]
The IETF
conducts standard-setting work groups, open to any individual,
about the various aspects ofInternet architecture. Resulting
discussions and final standards are published in a series of
publications, each called aRequest for Comments(RFC), freely
available on the IETF web site.
The principal methods of networking that enable the Internet are
contained in speciallydesignated RFCs that constitute theInternet
Standards. Other less rigorous documents are simply
informative, experimental, or historical, or document the best
current practices (BCP) when
implementing Internet technologies.
The Internet standards describe a framework known as theInternet
protocol suite. This is amodel architecture that divides methods
into a layered system of protocols (RFC 1122,RFC
1123). The layers correspond to the environment or scope in
which their services operate. At thetop is theapplication layer,
the space for the application-specific networking methods used
in
software applications, e.g., a web browser program uses
theclient-serverapplication model and
many file-sharing systems use apeer-to-peerparadigm. Below this
top layer, thetransport layerconnects applications on different
hosts via the network with appropriate data exchange methods.
Underlying these layers are the core networking technologies,
consisting of two layers. The
internet layerenables computers to identify and locate each
other viaInternet Protocol (IP)addresses, and allows them to
connect to one another via intermediate (transit) networks. Last,
at
the bottom of the architecture, is a software layer, thelink
layer, that provides connectivity
between hosts on the same local network link, such as a local
area network(LAN) or adial-upconnection. The model, also known as
TCP/IP, is designed to be independent of the underlyinghardware,
which the model therefore does not concern itself with in any
detail. Other models
have been developed, such as theOpen Systems
Interconnection(OSI) model, but they are not
compatible in the details of description or implementation; many
similarities exist and the
TCP/IP protocols are usually included in the discussion of OSI
networking.
http://en.wikipedia.org/wiki/Digital_subscriber_linehttp://en.wikipedia.org/wiki/Digital_subscriber_linehttp://en.wikipedia.org/wiki/Integrated_Services_Digital_Networkhttp://en.wikipedia.org/wiki/Integrated_Services_Digital_Networkhttp://en.wikipedia.org/wiki/Fiber_Distributed_Data_Interfacehttp://en.wikipedia.org/wiki/Fiber_Distributed_Data_Interfacehttp://en.wikipedia.org/wiki/Category:Link_protocolshttp://en.wikipedia.org/wiki/Category:Link_protocolshttp://en.wikipedia.org/wiki/Template:IPstackhttp://en.wikipedia.org/wiki/Template:IPstackhttp://en.wikipedia.org/wiki/Template_talk:IPstackhttp://en.wikipedia.org/wiki/Template_talk:IPstackhttp://en.wikipedia.org/w/index.php?title=Template:IPstack&action=edithttp://en.wikipedia.org/w/index.php?title=Template:IPstack&action=edithttp://en.wikipedia.org/wiki/Internet_Engineering_Task_Forcehttp://en.wikipedia.org/wiki/Internet_Engineering_Task_Forcehttp://en.wikipedia.org/wiki/Internet_Engineering_Task_Forcehttp://en.wikipedia.org/wiki/Internet#cite_note-29http://en.wikipedia.org/wiki/Internet#cite_note-29http://en.wikipedia.org/wiki/Internet#cite_note-29http://en.wikipedia.org/wiki/Request_for_Commentshttp://en.wikipedia.org/wiki/Request_for_Commentshttp://en.wikipedia.org/wiki/Request_for_Commentshttp://en.wikipedia.org/wiki/Internet_Standardhttp://en.wikipedia.org/wiki/Internet_Standardhttp://en.wikipedia.org/wiki/Internet_Standardhttp://en.wikipedia.org/wiki/Internet_protocol_suitehttp://en.wikipedia.org/wiki/Internet_protocol_suitehttp://en.wikipedia.org/wiki/Internet_protocol_suitehttp://tools.ietf.org/html/rfc1122http://tools.ietf.org/html/rfc1122http://tools.ietf.org/html/rfc1122http://tools.ietf.org/html/rfc1123http://tools.ietf.org/html/rfc1123http://tools.ietf.org/html/rfc1123http://tools.ietf.org/html/rfc1123http://en.wikipedia.org/wiki/Application_layerhttp://en.wikipedia.org/wiki/Application_layerhttp://en.wikipedia.org/wiki/Application_layerhttp://en.wikipedia.org/wiki/Client-serverhttp://en.wikipedia.org/wiki/Client-serverhttp://en.wikipedia.org/wiki/Client-serverhttp://en.wikipedia.org/wiki/Peer-to-peerhttp://en.wikipedia.org/wiki/Peer-to-peerhttp://en.wikipedia.org/wiki/Peer-to-peerhttp://en.wikipedia.org/wiki/Transport_layerhttp://en.wikipedia.org/wiki/Transport_layerhttp://en.wikipedia.org/wiki/Transport_layerhttp://en.wikipedia.org/wiki/Internet_layerhttp://en.wikipedia.org/wiki/Internet_layerhttp://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/Link_layerhttp://en.wikipedia.org/wiki/Link_layerhttp://en.wikipedia.org/wiki/Link_layerhttp://en.wikipedia.org/wiki/LANhttp://en.wikipedia.org/wiki/LANhttp://en.wikipedia.org/wiki/LANhttp://en.wikipedia.org/wiki/Dial-up_Internet_accesshttp://en.wikipedia.org/wiki/Dial-up_Internet_accesshttp://en.wikipedia.org/wiki/Dial-up_Internet_accesshttp://en.wikipedia.org/wiki/Dial-up_Internet_accesshttp://en.wikipedia.org/wiki/TCP/IPhttp://en.wikipedia.org/wiki/TCP/IPhttp://en.wikipedia.org/wiki/Open_Systems_Interconnectionhttp://en.wikipedia.org/wiki/Open_Systems_Interconnectionhttp://en.wikipedia.org/wiki/Open_Systems_Interconnectionhttp://en.wikipedia.org/wiki/Open_Systems_Interconnectionhttp://en.wikipedia.org/wiki/TCP/IPhttp://en.wikipedia.org/wiki/Dial-up_Internet_accesshttp://en.wikipedia.org/wiki/Dial-up_Internet_accesshttp://en.wikipedia.org/wiki/LANhttp://en.wikipedia.org/wiki/Link_layerhttp://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/Internet_layerhttp://en.wikipedia.org/wiki/Transport_layerhttp://en.wikipedia.org/wiki/Peer-to-peerhttp://en.wikipedia.org/wiki/Client-serverhttp://en.wikipedia.org/wiki/Application_layerhttp://tools.ietf.org/html/rfc1123http://tools.ietf.org/html/rfc1123http://tools.ietf.org/html/rfc1122http://en.wikipedia.org/wiki/Internet_protocol_suitehttp://en.wikipedia.org/wiki/Internet_Standardhttp://en.wikipedia.org/wiki/Request_for_Commentshttp://en.wikipedia.org/wiki/Internet#cite_note-29http://en.wikipedia.org/wiki/Internet_Engineering_Task_Forcehttp://en.wikipedia.org/w/index.php?title=Template:IPstack&action=edithttp://en.wikipedia.org/wiki/Template_talk:IPstackhttp://en.wikipedia.org/wiki/Template:IPstackhttp://en.wikipedia.org/wiki/Category:Link_protocolshttp://en.wikipedia.org/wiki/Fiber_Distributed_Data_Interfacehttp://en.wikipedia.org/wiki/Integrated_Services_Digital_Networkhttp://en.wikipedia.org/wiki/Digital_subscriber_line
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The most prominent component of the Internet model is the
Internet Protocol (IP), which
provides addressing systems (IP addresses) for computers on the
Internet. IP enables
internetworking and in essence establishes the Internet itself.
IP Version 4 (IPv4) is the initialversion used on the first
generation of today's Internet and is still in dominant use. It
was
designed to address up to ~4.3 billion (109) Internet hosts.
However, the explosive growth of the
Internet has led toIPv4 address exhaustion, which entered its
final stage in 2011,
[30]
when theglobal address allocation pool was exhausted. A new
protocol version, IPv6, was developed inthe mid-1990s, which
provides vastly larger addressing capabilities and more efficient
routing of
Internet traffic.IPv6is currently in growingdeploymentaround the
world, since Internet address
registries (RIRs) began to urge all resource managers to plan
rapid adoption and conversion.[31]
IPv6 is not interoperable with IPv4. In essence, it establishes
a parallel version of the Internet not
directly accessible with IPv4 software. This means software
upgrades or translator facilities arenecessary for networking
devices that need to communicate on both networks. Most modern
computer operating systems already support both versions of the
Internet Protocol. Network
infrastructures, however, are still lagging in this development.
Aside from the complex array of
physical connections that make up its infrastructure, the
Internet is facilitated by bi- or multi-lateral commercial
contracts (e.g.,peering agreements), and by technical
specifications or
protocols that describe how to exchange data over the network.
Indeed, the Internet is defined byits interconnections and routing
policies.
Routing
Internet packet routing is accomplished among various tiers of
Internet service providers.
Internet service providersconnect customers, which represent the
bottom of the routinghierarchy, to customers of other ISPs via
other higher or same-tier networks. At the top of the
routing hierarchy are theTier 1 networks, large
telecommunication companies which exchangetraffic directly with all
other Tier 1 networks viapeeringagreements.Tier 2 networksbuy
Internet transitfrom other providers to reach at least some
parties on the global Internet, though
they may also engage in peering. An ISP may use a single
upstream provider for connectivity, orimplementmultihomingto
achieve redundancy.Internet exchange pointsare major traffic
exchanges with physical connections to multiple ISPs.
http://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/IP_addresshttp://en.wikipedia.org/wiki/IPv4http://en.wikipedia.org/wiki/IPv4http://en.wikipedia.org/wiki/IPv4http://en.wikipedia.org/wiki/IPv4_address_exhaustionhttp://en.wikipedia.org/wiki/IPv4_address_exhaustionhttp://en.wikipedia.org/wiki/IPv4_address_exhaustionhttp://en.wikipedia.org/wiki/Internet#cite_note-30http://en.wikipedia.org/wiki/Internet#cite_note-30http://en.wikipedia.org/wiki/Internet#cite_note-30http://en.wikipedia.org/wiki/IPv6http://en.wikipedia.org/wiki/IPv6http://en.wikipedia.org/wiki/IPv6http://en.wikipedia.org/wiki/IPv6_deploymenthttp://en.wikipedia.org/wiki/IPv6_deploymenthttp://en.wikipedia.org/wiki/IPv6_deploymenthttp://en.wikipedia.org/wiki/Regional_Internet_registryhttp://en.wikipedia.org/wiki/Regional_Internet_registryhttp://en.wikipedia.org/wiki/Regional_Internet_registryhttp://en.wikipedia.org/wiki/Internet#cite_note-31http://en.wikipedia.org/wiki/Internet#cite_note-31http://en.wikipedia.org/wiki/Internet#cite_note-31http://en.wikipedia.org/wiki/Peering_agreementhttp://en.wikipedia.org/wiki/Peering_agreementhttp://en.wikipedia.org/wiki/Peering_agreementhttp://en.wikipedia.org/wiki/Internet_service_providerhttp://en.wikipedia.org/wiki/Internet_service_providerhttp://en.wikipedia.org/wiki/Tier_1_networkhttp://en.wikipedia.org/wiki/Tier_1_networkhttp://en.wikipedia.org/wiki/Tier_1_networkhttp://en.wikipedia.org/wiki/Peeringhttp://en.wikipedia.org/wiki/Peeringhttp://en.wikipedia.org/wiki/Peeringhttp://en.wikipedia.org/wiki/Tier_2_networkhttp://en.wikipedia.org/wiki/Tier_2_networkhttp://en.wikipedia.org/wiki/Tier_2_networkhttp://en.wikipedia.org/wiki/Internet_transithttp://en.wikipedia.org/wiki/Internet_transithttp://en.wikipedia.org/wiki/Multihominghttp://en.wikipedia.org/wiki/Multihominghttp://en.wikipedia.org/wiki/Multihominghttp://en.wikipedia.org/wiki/Internet_exchange_pointhttp://en.wikipedia.org/wiki/Internet_exchange_pointhttp://en.wikipedia.org/wiki/Internet_exchange_pointhttp://en.wikipedia.org/wiki/File:Internet_Connectivity_Distribution_&_Core.svghttp://en.wikipedia.org/wiki/File:Internet_Connectivity_Distribution_&_Core.svghttp://en.wikipedia.org/wiki/File:Internet_Connectivity_Distribution_&_Core.svghttp://en.wikipedia.org/wiki/File:Internet_Connectivity_Distribution_&_Core.svghttp://en.wikipedia.org/wiki/Internet_exchange_pointhttp://en.wikipedia.org/wiki/Multihominghttp://en.wikipedia.org/wiki/Internet_transithttp://en.wikipedia.org/wiki/Tier_2_networkhttp://en.wikipedia.org/wiki/Peeringhttp://en.wikipedia.org/wiki/Tier_1_networkhttp://en.wikipedia.org/wiki/Internet_service_providerhttp://en.wikipedia.org/wiki/Peering_agreementhttp://en.wikipedia.org/wiki/Internet#cite_note-31http://en.wikipedia.org/wiki/Regional_Internet_registryhttp://en.wikipedia.org/wiki/IPv6_deploymenthttp://en.wikipedia.org/wiki/IPv6http://en.wikipedia.org/wiki/Internet#cite_note-30http://en.wikipedia.org/wiki/IPv4_address_exhaustionhttp://en.wikipedia.org/wiki/IPv4http://en.wikipedia.org/wiki/IP_address
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Computers and routers userouting tablesto direct IP packets to
the next-hop router or
destination. Routing tables are maintained by manual
configuration or byrouting protocols. End-
nodes typically use adefault routethat points toward an ISP
providing transit, while ISP routersuse theBorder Gateway
Protocolto establish the most efficient routing across the
complex
connections of the global Internet.
Large organizations, such as academic institutions, large
enterprises, and governments, may
perform the same function as ISPs, engaging in peering and
purchasing transit on behalf of their
internal networks. Research networks tend to interconnect into
large subnetworks such asGEANT,GLORIAD,Internet2, and the
UK'snational research and education network,JANET.
General structure
The Internet structure and its usage characteristics have been
studied extensively. It has been
determined that both the Internet IP routing structure and
hypertext links of the World Wide Web
are examples ofscale-free networks.[32]
Many computer scientists describe the Internet as a "prime
example of a large-scale, highly
engineered, yet highly complex system".[33]
The Internet is heterogeneous; for instance,datatransfer
ratesand physical characteristics of connections vary widely. The
Internet exhibits
"emergent phenomena" that depend on its large-scale
organization. For example, data transfer
rates exhibit temporalself-similarity. The principles of the
routing and addressing methods fortraffic in the Internet reach
back to their origins in the 1960s when the eventual scale and
popularity of the network could not be anticipated.[34]
Thus, the possibility of developing
alternative structures is investigated.[35]
The Internet structure was found to be highly robust[36]
to
random failures
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