IP networks are divided logically into subnetworks. Computers in the same subnetwork have the same address prefix. For example, in a typical home network with legacy Internet Protocol version 4, the network prefix would be something like 192.168.1.0/24, as expressed in CIDR notation.
With IPv4, commonly home networks use private addresses (defined in RFC1918) that are non-routable on the public Internet and use address translation to convert to routable addresses when connecting to hosts outside the local network. Business networks typically had manually provisioned subnetwork prefixes. In IPv6 global addresses are used end-to-end, so even home networks may need to distribute public, routable IP addresses to hosts.
Since it would not be practical to manually provision networks at scale, in IPv6 networking, DHCPv6prefix delegation ( RFC3633; RFC8415 § 6.3) is used to assign a network address prefix and automate configuration and provisioning of the public routable addresses for the network. In the typical case of a home network, for example, the home router uses DHCPv6 to request a network prefix from the ISP's DHCPv6 server. Once assigned, the ISP routes this network to the customer's home router and the home router starts advertising the new address space to hosts on the network, either via SLAAC or using DHCPv6.
DHCPv6 Prefix Delegation is supported by most ISPs who provide native IPv6 for consumers on fixed networks.
Prefix delegation is generally not supported on cellular networks, for example LTE or 5G. Most cellular networks route a fixed /64 prefix to the subscriber. Personal hotspots may still provide IPv6 access to hosts on the network by using a different technique called Proxy Neighbor Discovery or using the technique described in RFC7278. One of the reasons why cellular networks may not yet support prefix delegation is that the operators want to use prefixes they can aggregate to a single route. To solve this, RFC6603 defines an optional mechanism and the related DHCPv6 option to allow exclusion of one specific prefix from a delegated prefix set.
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 client–server architecture.
An Internet Protocol address is a numerical label such as 192.0.2.1 that is assigned to a device connected to a computer network that uses the Internet Protocol for communication. IP addresses serve two main functions: network interface identification, and location addressing.
Internet Protocol version 4 (IPv4) is the fourth version of the Internet Protocol (IP). It is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks. IPv4 was the first version deployed for production on SATNET in 1982 and on the ARPANET in January 1983. It is still used to route most Internet traffic today, even with the ongoing deployment of Internet Protocol version 6 (IPv6), its successor.
Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), the communications protocol that provides an identification and location system for computers on networks and routes traffic across the Internet. IPv6 was developed by the Internet Engineering Task Force (IETF) to deal with the long-anticipated problem of IPv4 address exhaustion, and was intended to replace IPv4. In December 1998, IPv6 became a Draft Standard for the IETF, which subsequently ratified it as an Internet Standard on 14 July 2017.
Classless Inter-Domain Routing is a method for allocating IP addresses for IP routing. The Internet Engineering Task Force introduced CIDR in 1993 to replace the previous classful network addressing architecture on the Internet. Its goal was to slow the growth of routing tables on routers across the Internet, and to help slow the rapid exhaustion of IPv4 addresses.
A multicast address is a logical identifier for a group of hosts in a computer network that are available to process datagrams or frames intended to be multicast for a designated network service. Multicast addressing can be used in the link layer, such as Ethernet multicast, and at the internet layer for Internet Protocol Version 4 (IPv4) or Version 6 (IPv6) multicast.
Network address translation (NAT) is a method of mapping an IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic routing device. The technique was originally used to bypass the need to assign a new address to every host when a network was moved, or when the upstream Internet service provider was replaced, but could not route the network's address space. It has become a popular and essential tool in conserving global address space in the face of IPv4 address exhaustion. One Internet-routable IP address of a NAT gateway can be used for an entire private network.
A subnetwork, or subnet, is a logical subdivision of an IP network. The practice of dividing a network into two or more networks is called subnetting.
Zero-configuration networking (zeroconf) is a set of technologies that automatically creates a usable computer network based on the Internet Protocol Suite (TCP/IP) when computers or network peripherals are interconnected. It does not require manual operator intervention or special configuration servers. Without zeroconf, a network administrator must set up network services, such as Dynamic Host Configuration Protocol (DHCP) and Domain Name System (DNS), or configure each computer's network settings manually.
In Internet networking, a private network is a computer network that uses a private address space of IP addresses. These addresses are commonly used for local area networks (LANs) in residential, office, and enterprise environments. Both the IPv4 and the IPv6 specifications define private IP address ranges.
Mobile IP is an Internet Engineering Task Force (IETF) standard communications protocol that is designed to allow mobile device users to move from one network to another while maintaining a permanent IP address. Mobile IP for IPv4 is described in IETF RFC 5944, and extensions are defined in IETF RFC 4721. Mobile IPv6, the IP mobility implementation for the next generation of the Internet Protocol, IPv6, is described in RFC 6275.
In computer networking, Teredo is a transition technology that gives full IPv6 connectivity for IPv6-capable hosts that are on the IPv4 Internet but have no native connection to an IPv6 network. Unlike similar protocols such as 6to4, it can perform its function even from behind network address translation (NAT) devices such as home routers.
The Neighbor Discovery Protocol (NDP), or simply Neighbor Discovery (ND), is a protocol of the Internet protocol suite used with Internet Protocol Version 6 (IPv6). It operates at the internet layer of the Internet model, and is responsible for gathering various information required for network communication, including the configuration of local connections and the domain name servers and gateways.
The Dynamic Host Configuration Protocol version 6 (DHCPv6) is a network protocol for configuring Internet Protocol version 6 (IPv6) hosts with IP addresses, IP prefixes, default route, local segment MTU, and other configuration data required to operate in an IPv6 network. It is not just the IPv6 equivalent of the Dynamic Host Configuration Protocol for IPv4.
In computer networking, a link-local address is an network address that is valid only for communications on a local link, i.e. within a subnetwork that a host is connected to. Link-local addresses are most often unicast network addresses assigned automatically through a process known as stateless address autoconfiguration (SLAAC) or link-local address autoconfiguration, also known as automatic private IP addressing (APIPA) or auto-IP. Link-local addresses are not all unicast; e.g. IPv6 addresses beginning with ff02:, and IPv4 addresses beginning with 224.0.0. are multicast addresses that are link-local.
An IPv6 transition mechanism is a technology that facilitates the transitioning of the Internet from the Internet Protocol version 4 (IPv4) infrastructure in use since 1983 to the successor addressing and routing system of Internet Protocol Version 6 (IPv6). As IPv4 and IPv6 networks are not directly interoperable, transition technologies are designed to permit hosts on either network type to communicate with any other host.
Proxy Mobile IPv6 is a network-based mobility management protocol standardized by IETF and is specified in RFC 5213. It is a protocol for building a common and access technology independent of mobile core networks, accommodating various access technologies such as WiMAX, 3GPP, 3GPP2 and WLAN based access architectures. Proxy Mobile IPv6 is the only network-based mobility management protocol standardized by IETF.
Locator/ID Separation Protocol (LISP) is a "map-and-encapsulate" protocol which is developed by the Internet Engineering Task Force LISP Working Group. The basic idea behind the separation is that the Internet architecture combines two functions, routing locators and identifiers in one number space: the IP address. LISP supports the separation of the IPv4 and IPv6 address space following a network-based map-and-encapsulate scheme. In LISP, both identifiers and locators can be IP addresses or arbitrary elements like a set of GPS coordinates or a MAC address.
An Internet Protocol Version 6 address is a numeric label that is used to identify and locate a network interface of a computer or a network node participating in a computer network using IPv6. IP addresses are included in the packet header to indicate the source and the destination of each packet. The IP address of the destination is used to make decisions about routing IP packets to other networks.
Port Control Protocol (PCP) is a computer networking protocol that allows hosts on IPv4 or IPv6 networks to control how the incoming IPv4 or IPv6 packets are translated and forwarded by an upstream router that performs network address translation (NAT) or packet filtering. By allowing hosts to create explicit port forwarding rules, handling of the network traffic can be easily configured to make hosts placed behind NATs or firewalls reachable from the rest of the Internet, which is a requirement for many applications.
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