IPv6 - Knowledge (XXG)

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called "privacy addresses" or, more correctly, "temporary addresses". Temporary addresses are random and unstable. A typical consumer device generates a new temporary address daily and will ignore traffic addressed to an old address after one week. Temporary addresses are used by default by Windows since XP SP1, macOS since (Mac OS X) 10.7, Android since 4.0, and iOS since version 4.3. Use of temporary addresses by Linux distributions varies.

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stack requires that the resolving DNS server can resolve both types of addresses. Such a dual-stack DNS server holds IPv4 addresses in the A records and IPv6 addresses in the AAAA records. Depending on the destination that is to be resolved, a DNS name server may return an IPv4 or IPv6 IP address, or both. A default address selection mechanism, or preferred protocol, needs to be configured either on hosts or the DNS server. The

2050:, causing IPv6 traffic flowing into networks having only IPv4 security management in place. This may also occur with operating system upgrades, when the newer operating system enables IPv6 by default, while the older one did not. Failing to update the security infrastructure to accommodate IPv6 can lead to IPv6 traffic bypassing it. Shadow networks have occurred on business networks in which enterprises are replacing 83: 907:, the transmission of a packet to multiple destinations in a single send operation, is part of the base specification in IPv6. In IPv4 this is an optional (although commonly implemented) feature. IPv6 multicast addressing has features and protocols in common with IPv4 multicast, but also provides changes and improvements by eliminating the need for certain protocols. IPv6 does not implement traditional 1232:

subnet always uses 64 bits for the host portion of the address, designated as the interface identifier, while the most-significant 64 bits are used as the routing prefix. While the myth has existed regarding IPv6 subnets being impossible to scan, RFC 7707 notes that patterns resulting from some IPv6 address configuration techniques and algorithms allow address scanning in many real-world scenarios.

2105: 888:(CIDR) methods were developed to make the best use of the small address space. The standard size of a subnet in IPv6 is 2 addresses, about four billion times the size of the entire IPv4 address space. Thus, actual address space utilization will be small in IPv6, but network management and routing efficiency are improved by the large subnet space and hierarchical route aggregation. 985:(IKE) was recommended, but with RFC 6434 the inclusion of IPsec in IPv6 implementations was downgraded to a recommendation because it was considered impractical to require full IPsec implementation for all types of devices that may use IPv6. However, as of RFC 4301 IPv6 protocol implementations that do implement IPsec need to implement IKEv2 and need to support a minimum set of 1129: 843:, designed to minimize packet header processing by routers. Because the headers of IPv4 packets and IPv6 packets are significantly different, the two protocols are not interoperable. However, most transport and application-layer protocols need little or no change to operate over IPv6; exceptions are application protocols that embed Internet-layer addresses, such as 1491:

response, known as a router advertisement, from a router, the response includes the network configuration information to allow establishment of a globally unique address with an appropriate unicast network prefix. There are also two flag bits that tell the host whether it should use DHCP to get further information and addresses:

1826:(ISPs) are increasingly providing their business and private customers with public-facing IPv6 global unicast addresses. If IPv4 is still used in the local area network (LAN), however, and the ISP can only provide one public-facing IPv6 address, the IPv4 LAN addresses are translated into the public facing IPv6 address using 1418:. This prefix is followed by 54 bits that can be used for subnetting, although they are typically set to zeros, and a 64-bit interface identifier. The host can compute and assign the Interface identifier by itself without the presence or cooperation of an external network component like a DHCP server, in a process called 1006:. However, many devices implement IPv6 support in software (as opposed to hardware), thus resulting in very bad packet processing performance. Additionally, for many implementations, the use of Extension Headers causes packets to be processed by a router's CPU, leading to poor performance or even security issues. 2120:(IETF) in the early 1990s started an effort to develop a next generation IP protocol. By the beginning of 1992, several proposals appeared for an expanded Internet addressing system and by the end of 1992 the IETF announced a call for white papers. In September 1993, the IETF created a temporary, ad hoc 583:

for identification and location definition. With the rapid growth of the Internet after commercialization in the 1990s, it became evident that far more addresses would be needed to connect devices than the IPv4 address space had available. By 1998, the IETF had formalized the successor protocol. IPv6

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While some ISPs still allocate customers only IPv4 addresses, many ISPs allocate their customers only an IPv6 or dual-stack IPv4 and IPv6. ISPs report the share of IPv6 traffic from customers over their network to be anything between 20% and 40%, but by mid-2017 IPv6 traffic still only accounted for

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The lower 64 bits of the link-local address (the suffix) were originally derived from the MAC address of the underlying network interface card. As this method of assigning addresses would cause undesirable address changes when faulty network cards were replaced, and as it also suffered from a number

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Renumbering an existing network for a new connectivity provider with different routing prefixes is a major effort with IPv4. With IPv6, however, changing the prefix announced by a few routers can in principle renumber an entire network, since the host identifiers (the least-significant 64 bits of an

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A host bringing up a new IPv6 interface first generates a unique link-local address using one of several mechanisms designed to generate a unique address. Should a non-unique address be detected, the host can try again with a newly generated address. Once a unique link-local address is established,

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have 128 bits. The design of the IPv6 address space implements a different design philosophy than in IPv4, in which subnetting was used to improve the efficiency of utilization of the small address space. In IPv6, the address space is deemed large enough for the foreseeable future, and a local area

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IPv6 hosts configure themselves automatically. Every interface has a self-generated link-local address and, when connected to a network, conflict resolution is performed and routers provide network prefixes via router advertisements. Stateless configuration of routers can be achieved with a special

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to assist dual-stack applications, so that they can connect using both IPv4 and IPv6, but prefer an IPv6 connection if it is available. However, dual-stack also needs to be implemented on all routers between the host and the service for which the DNS server has returned an IPv6 address. Dual-stack

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interface that supports IPv6. It does so by sending out an ICMPv6 router solicitation message to the all-routers multicast group with its link-local address as source. If there is no answer after a predetermined number of attempts, the host concludes that no routers are connected. If it does get a

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for IPv6 have at least a 64-bit routing prefix, yielding the smallest subnet size available in IPv6 (also 64 bits). With such an assignment it is possible to embed the unicast address prefix into the IPv6 multicast address format, while still providing a 32-bit block, the least significant bits of

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A device with dual-stack implementation in the operating system has an IPv4 and IPv6 address, and can communicate with other nodes in the LAN or the Internet using either IPv4 or IPv6. The DNS protocol is used by both IP protocols to resolve fully qualified domain names and IP addresses, but dual

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to tunnel over IPv4 networks, by encapsulating IPv6 packets within UDP. The Teredo relay is an IPv6 router that mediates between a Teredo server and the native IPv6 network. It was expected that 6to4 and Teredo would be widely deployed until ISP networks would switch to native IPv6, but by 2014

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reported 7%. A 2017 survey found that many DSL customers that were served by a dual stack ISP did not request DNS servers to resolve fully qualified domain names into IPv6 addresses. The survey also found that the majority of traffic from IPv6-ready web-server resources were still requested and

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A stable, unique, globally addressable IP address would facilitate tracking a device across networks. Therefore, such addresses are a particular privacy concern for mobile devices, such as laptops and cell phones. To address these privacy concerns, the SLAAC protocol includes what are typically

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Because of the significant internal differences between IPv4 and IPv6 protocol stacks, some of the lower-level functionality available to programmers in the IPv6 stack does not work the same when used with IPv4-mapped addresses. Some common IPv6 stacks do not implement the IPv4-mapped address

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multicast group at address ff02::1, which is analogous to IPv4 multicasting to address 224.0.0.1. IPv6 also provides for new multicast implementations, including embedding rendezvous point addresses in an IPv6 multicast group address, which simplifies the deployment of inter-domain solutions.

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The IPv6 packet header has a minimum size of 40 octets (320 bits). Options are implemented as extensions. This provides the opportunity to extend the protocol in the future without affecting the core packet structure. However, RFC 7872 notes that some network operators drop IPv6 packets with

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as decimal values of four octets, each in the range 0 to 255, or 8 bits per number. Thus, IPv4 provides an addressing capability of 2 or approximately 4.3 billion addresses. Address exhaustion was not initially a concern in IPv4 as this version was originally presumed to be a test of DARPA's

1002:. Although IPv6 packet headers are at least twice the size of IPv4 packet headers, processing of packets that only contain the base IPv6 header by routers may, in some cases, be more efficient, because less processing is required in routers due to the headers being aligned to match common 668:

In addition to offering more addresses, IPv6 also implements features not present in IPv4. It simplifies aspects of address configuration, network renumbering, and router announcements when changing network connectivity providers. It simplifies packet processing in routers by placing the

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By 2011, all major operating systems in use on personal computers and server systems had production-quality IPv6 implementations. Cellular telephone systems presented a large deployment field for Internet Protocol devices as mobile telephone service made the transition from

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field tells the receiver how to interpret the data which follows the header. If the packet contains options, this field contains the option type of the next option. The "Next Header" field of the last option points to the upper-layer protocol that is carried in the packet's

1834:(NAT) mechanism. Some ISPs cannot provide their customers with public-facing IPv4 and IPv6 addresses, thus supporting dual-stack networking, because some ISPs have exhausted their globally routable IPv4 address pool. Meanwhile, ISP customers are still trying to reach IPv4 1743:, a dual-stack implementation of the IPv4 and IPv6 on devices is the easiest way to migrate to IPv6. Many other transition mechanisms use tunneling to encapsulate IPv6 traffic within IPv4 networks and vice versa. This is an imperfect solution, which reduces the 1498:

The Other bit, which indicates whether or not the host should obtain other information through DHCP. The other information consists of one or more prefix information options for the subnets that the host is attached to, a lifetime for the prefix, and two flags:

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Hybrid dual-stack IPv6/IPv4 implementations recognize a special class of addresses, the IPv4-mapped IPv6 addresses. These addresses are typically written with a 96-bit prefix in the standard IPv6 format, and the remaining 32 bits are written in the customary

989:. This requirement will help to make IPsec implementations more interoperable between devices from different vendors. The IPsec Authentication Header (AH) and the Encapsulating Security Payload header (ESP) are implemented as IPv6 extension headers. 859:

The main advantage of IPv6 over IPv4 is its larger address space. The size of an IPv6 address is 128 bits, compared to 32 bits in IPv4. The address space therefore has 2=340,282,366,920,938,463,463,374,607,431,768,211,456 addresses (340

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Consecutive sections of zeros are replaced with two colons (::). This may only be used once in an address, as multiple use would render the address indeterminate. A double colon should not be used to denote an omitted single section of

615:. The use of multicast addressing is expanded and simplified, and provides additional optimization for the delivery of services. Device mobility, security, and configuration aspects have been considered in the design of the protocol. 1383:

Because IPv6 addresses contain colons, and URLs use colons to separate the host from the port number, an IPv6 address used as the host-part of a URL should be enclosed in square brackets, e.g. http:// or http://:8080/path/page.html.

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networking concepts. During the first decade of operation of the Internet, it became apparent that methods had to be developed to conserve address space. In the early 1990s, even after the redesign of the addressing system using a

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The assignment procedure for global addresses is similar to local-address construction. The prefix is supplied from router advertisements on the network. Multiple prefix announcements cause multiple addresses to be configured.

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requires that the first fragment of an IPv6 packet contains the entire IPv6 header chain, such that some very pathological fragmentation cases are forbidden. Additionally, as a result of research on the evasion of RA-Guard in

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While this address space is very large, it was not the intent of the designers of IPv6 to assure geographical saturation with usable addresses. Rather, the longer addresses simplify allocation of addresses, enable efficient

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the address, or approximately 4.2 billion multicast group identifiers. Thus each user of an IPv6 subnet automatically has available a set of globally routable source-specific multicast groups for multicast applications.

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of Internet design, which envisioned that most processing in the network occurs in the leaf nodes. Integrity protection for the data that is encapsulated in the IPv6 packet is assumed to be assured by both the

1669:(FQDN), the DNS client of the host sends two DNS requests, one querying A records and the other querying AAAA records. The host operating system may be configured with a preference for address selection rules 1502:

On-link: If this flag is set, the host will treat all addresses on the specific subnet as being on-link and send packets directly to them instead of sending them to a router for the duration of the given

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The packet header in IPv6 is simpler than the IPv4 header. Many rarely used fields have been moved to optional header extensions. The IPv6 packet header has simplified the process of packet forwarding by

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In IPv4 it is very difficult for an organization to get even one globally routable multicast group assignment, and the implementation of inter-domain solutions is arcane. Unicast address assignments by a

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The technical basis for tunneling, or encapsulating IPv6 packets in IPv4 packets, is outlined in RFC 4213. When the Internet backbone was IPv4-only, one of the frequently used tunneling protocols was

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systems, that do. Some IPv6 stack implementors have therefore recommended disabling IPv4 mapped addresses and instead using a dual-stack network where supporting both IPv4 and IPv6 is necessary.

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began experimental IPv6 deployment in 2003 and by 2016 the IPv6 traffic on their networks averaged between 20% and 40%. A significant portion of this IPv6 traffic was generated through their

981:(IPsec) was originally developed for IPv6, but found widespread deployment first in IPv4, for which it was re-engineered. IPsec was a mandatory part of all IPv6 protocol implementations, and 2318:(BGP) routing database. A further 243 networks advertised only an IPv6 prefix. Internet backbone transit networks offering IPv6 support existed in every country globally, except in parts of 1154:(320 bits) of the IPv6 packet. It contains the source and destination addresses, traffic class, hop count, and the type of the optional extension or payload which follows the header. This 596:

total addresses. The actual number is slightly smaller, as multiple ranges are reserved for special usage or completely excluded from general use. The two protocols are not designed to be

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A number of security implications may arise from the use of IPv6. Some of them may be related with the IPv6 protocols themselves, while others may be related with implementation flaws.

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The Manage bit, which indicates whether or not the host should use DHCP to obtain additional addresses rather than rely on an auto-configured address from the router advertisement.

955:. The design of IPv6 intended to re-emphasize the end-to-end principle of network design that was originally conceived during the establishment of the early Internet by rendering 4599: 4408: 2737: 4884: 812:(AFRINIC) as the sole regional internet registry that is still using the normal protocol for distributing IPv4 addresses. As of November 2018, AFRINIC's minimum allocation is 1951:

Addresses in this group consist of an 80-bit prefix of zeros, the next 16 bits are ones, and the remaining, least-significant 32 bits contain the IPv4 address. For example,

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served over IPv4, mostly due to ISP customers that did not use the dual stack facility provided by their ISP and to a lesser extent due to customers of IPv4-only ISPs.

5426: 1482:(LAN) by sending a neighbor solicitation message asking for the link-layer address of the IP address. If any other host in the LAN is using that address, it responds. 1147:

The header consists of a fixed portion with minimal functionality required for all packets and may be followed by optional extensions to implement special features.

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IPv6 provides other technical benefits in addition to a larger addressing space. In particular, it permits hierarchical address allocation methods that facilitate

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Extension headers carry options that are used for special treatment of a packet in the network, e.g., for routing, fragmentation, and for security using the

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released technical specifications for devices to operate on its "next-generation" networks. The specification mandated IPv6 operation according to the

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and is therefore as efficient as native IPv6. IPv6 routers may also allow entire subnets to move to a new router connection point without renumbering.

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The Internet Engineering Task Force adopted the IPng model on 25 July 1994, with the formation of several IPng working groups. By 1996, a series of

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are needed to enable IPv6 hosts to reach IPv4 services and to allow isolated IPv6 hosts and networks to reach each other over IPv4 infrastructure.

1042:. Thus, while IPv4 allowed UDP datagram headers to have no checksum (indicated by 0 in the header field), IPv6 requires a checksum in UDP headers. 5400: 4566: 793: 5079: 2091:

has deprecated the use of fragmentation with Neighbor Discovery, and discouraged the use of fragmentation with Secure Neighbor Discovery (SEND).

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The 128 bits of an IPv6 address are represented in 8 groups of 16 bits each. Each group is written as four hexadecimal digits (sometimes called

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RIPE NCC announced that it had fully run out of IPv4 addresses on 25 November 2019, and called for greater progress on the adoption of IPv6.

521: 248: 2845: 777:(RIRs). However, each RIR still has available address pools and is expected to continue with standard address allocation policies until one 378: 373: 343: 970:

The SLAAC address generation method is implementation-dependent. IETF recommends that addresses be deterministic but semantically opaque.

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IPv6 is not foreseen to supplant IPv4 instantaneously. Both protocols will continue to operate simultaneously for some time. Therefore,

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transmission across multiple IP networks, closely adhering to the design principles developed in the previous version of the protocol,

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s are specifically considered. It remains to be seen whether ISPs will honor this recommendation. For example, during initial trials,

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Research has shown that the use of fragmentation can be leveraged to evade network security controls, similar to IPv4. As a result,

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was also frequently used for integrating IPv6 LANs with the IPv4 Internet backbone. Teredo is outlined in RFC 4380 and allows IPv6

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IPv4 limits packets to 65,535 (2−1) octets of payload. An IPv6 node can optionally handle packets over this limit, referred to as

5436: 5132: 1171: 514: 445: 238: 915:, and therefore does not define broadcast addresses. In IPv6, the same result is achieved by sending a packet to the link-local 4784: 4199: 3831: 3102: 2667: 2532: 2493: 2117: 561: 115: 4832: 3070: 1987:). On these operating systems, a program must open a separate socket for each IP protocol it uses. On some systems, e.g., the 5252: 4858: 4121: 3183: 2414: 2399: 2238: 885: 785: 759: 263: 253: 2046:

The addition of nodes having IPv6 enabled by default by the software manufacturer may result in the inadvertent creation of

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from any group of hexadecimal digits are removed, which is usually done to all of the leading zeros. For example, the group

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clients should be configured to prefer IPv6 only if the network is able to forward IPv6 packets using the IPv6 versions of

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An alternative record type was used in early DNS implementations for IPv6, designed to facilitate network renumbering, the

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continued. In 2018 only 25.3% of the about 54,000 autonomous systems advertised both IPv4 and IPv6 prefixes in the global

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blocks, which they divide among subordinate networks. The initial recommendation of September 2001 stated assignment of a

1031: 383: 363: 313: 2710: 5383: 1095: 1003: 303: 298: 293: 5378: 4143: 2242: 1831: 1666: 1463: 1459: 956: 715: 480: 440: 308: 2279:(DNS) has supported IPv6 since 2008. In the same year, IPv6 was first used in a major world event during the Beijing 4987: 2565: 1392: 5393: 2230: 1842: 1823: 978: 774: 3415: 5388: 5352: 5082:(Press release). The Beijing Organizing Committee for the Games of the XXIX Olympiad. 30 May 2008. Archived from 2797: 2149: 1870: 1744: 1733: 1727: 1455: 1111: 1054: 769:

The last unassigned top-level address blocks of 16 million IPv4 addresses were allocated in February 2011 by the

601: 5059: 1927: 2444: 2176: 1517: 1110:, which can be as large as 4,294,967,295 (2−1) octets. The use of jumbograms may improve performance over high- 333: 273: 1271:

For convenience and clarity, the representation of an IPv6 address may be shortened with the following rules:

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that provides an identification and location system for computers on networks and routes traffic across the

500: 490: 283: 198: 182: 1935: 788:(CIDR) block remains. After that, only blocks of 1,024 addresses (/22) will be provided from the RIRs to a 2354:

had an IPv6 deployment of about 66%. In 2018 Xfinity reported an estimated 36.1 million IPv6 users, while

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Dual-stack IP implementations provide complete IPv4 and IPv6 protocol stacks in the operating system of a

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obsolete. Therefore, every device on the network is globally addressable directly from any other device.

2371: 982: 896: 873: 848: 495: 268: 4554: 5083: 4523: 3791: 2385: 1815: 4940: 4806: 4756: 4675: 4447: 4221: 4167: 3948: 3895: 3853: 3676: 3599: 3541: 3495: 3454: 3349: 3230: 3124: 3049: 3003: 2681: 2280: 2164: 1945: 1858: 1022: 1010: 908: 754: 278: 162: 572:. In December 1998, IPv6 became a Draft Standard for the IETF, which subsequently ratified it as an 2265: 1915: 1160: 1141: 1021:

in the IPv6 protocol) is reduced by one. The absence of a checksum in the IPv6 header furthers the

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router renumbering protocol. When necessary, hosts may configure additional stateful addresses via

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to make their packets small enough to reach the destination without needing to be fragmented. See

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size is standardized by fixing the size of the host identifier portion of an address to 64 bits.

485: 213: 2524: 2485: 1845:(RIR) zones have obtained IPv6 address space. This includes many of the world's major ISPs and 5261: 4798: 4774: 4667: 4626: 4477: 4333: 4282: 4213: 4073: 4030: 3845: 3801: 3767: 3763: 3757: 3736: 3381: 3371: 3116: 2811: 2617: 2607: 2536: 2311: 2211:, which elevated IPv6 to "Internet Standard" (the highest maturity level for IETF protocols). 1980: 1862: 1797: 1793: 1151: 1058: 881: 742: 731: 638: 608: 573: 549: 413: 189: 3726: 824:

may receive additional allocation when about 80% of all the address space has been utilized.

5162: 5065: 5039: 5006: 4959: 4788: 4746: 4657: 4437: 4372: 4362: 4203: 4157: 4089: 4081: 4048: 4038: 4011: 3938: 3885: 3835: 3666: 3589: 3531: 3485: 3444: 3339: 3308: 3300: 3267: 3259: 3220: 3187: 3136: 3106: 3039: 2993: 2962: 2942: 2922: 2902: 2883: 2671: 2569: 2544: 2497: 2335: 2204: 2196: 2188: 2168: 2084: 2076: 2067: 1911: 1850: 1804: 1711: 1703: 1695: 1670: 1655: 1435: 1427: 1046: 677: 651: 2241:(CIDR) in the routing and IP address allocation for the Internet, and the extensive use of 1220: 5309: 5106: 3920: 2391: 2225: 2220: 1874: 1752: 1085: 1039: 654: 354: 104: 4302: 1779:. This permits dual-stack hosts to participate in IPv6 and IPv4 networks simultaneously. 622:

digits each, separated by colons. The full representation may be shortened; for example,

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Cicileo, Guillermo; Gagliano, Roque; O’Flaherty, Christian; et al. (October 2009).

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Narten, T. (August 1999). "Neighbor discovery and stateless autoconfiguration in IPv6".

2299:(VoIP) service that would leverage IPv6 enhancements. In 2009, the US cellular operator 2256:

deployed IPv6 at a trial location in 2004 and later expanded IPv6 deployment across the

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and network device vendors, legacy networking hardware and servers do not support IPv6.

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links. The use of jumbograms is indicated by the Jumbo Payload Option extension header.

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is calculated for the IPv4 header, and has to be recalculated by routers every time the

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Please help update this article to reflect recent events or newly available information.

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Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers

2257: 2145: 2125: 1846: 1788: 1772: 1768: 851:(NTP), where the new address format may cause conflicts with existing protocol syntax. 836: 750: 647: 404: 74: 911:, i.e. the transmission of a packet to all hosts on the attached link using a special 5421: 5415: 5238: 3656: 3475: 3400: 2520: 2481: 2350:

had 73% and 63% IPv6 deployment respectively. In the United States the broadband ISP

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feature, either because the IPv6 and IPv4 stacks are separate implementations (e.g.,

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and its references (with further discussion of the pros and cons of both schemes in

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has replaced the original MAC-based method with the hash-based method specified in

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Google Statistics showed that the use of both mechanisms had dropped to almost 0.

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subnet to end-consumer sites. In March 2011 this recommendation was refined: The

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IPv6 uses a new mechanism for mapping IP addresses to link-layer addresses (e.g.

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As an IPv6 address may have more than one representation, the IETF has issued a

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IPv6 For All: A Guide for IPv6 Usage and Application in Different Environments

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Unlike with IPv4, routers never fragment a packet. Hosts are expected to use

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The current use of the IPv6 Traffic Class field divides this between a 6 bit

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Temporary Address Extensions for Stateless Address Autoconfiguration in IPv6

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transmission. IPv6 hosts verify the uniqueness of their IPv6 addresses in a

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R. Gilligan; S. Thomson; J. Bound; J. McCann; W. Stevens (February 2003).

3252:"Network Renumbering Overview: Why would I want it and what is it anyway?" 2734:"IPv4 Address Exhaustion Not Instant Cause for Concern with IPv6 in Wings" 1486:

the IPv6 host determines whether the LAN is connected on this link to any

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Parts of this article (those related to RFC 8200 and RFC 8201) need to be

17: 4727: 4117: 3161: 2849: 2765: 2113: 1866: 1776: 1764: 1684:

records for the forward lookup and a number of other innovations such as

1631: 797: 746: 658: 557: 4015: 3216:

Network Renumbering Overview: Why would I want it and what is it anyway?

2931:

Embedding the Rendezvous Point (RP) Address in an IPv6 Multicast Address

2342:

in the Netherlands had 73% deployment and in Belgium the broadband ISPs

2167:

was released defining Internet Protocol version 6 (IPv6), starting with

1128: 5218: 4723: 4251: 4248:"Comcast Activates First Users With IPv6 Native Dual Stack Over DOCSIS" 2879: 2819: 2355: 2351: 2347: 1996: 1984: 1604: 809: 766:, and that further changes to the Internet infrastructure were needed. 689: 685: 5212: 5011: 4964: 4955: 4377: 4094: 4053: 3313: 3272: 2888: 2793: 2549: 2502: 1506:

Address: This flag tells the host to actually create a global address.

5368: 5003:"The Recommendation for the IP Next Generation Protocol – Appendix B" 4793: 4751: 4662: 4442: 4367: 4208: 4162: 4085: 4043: 3943: 3890: 3840: 3797: 3671: 3594: 3536: 3490: 3449: 3437:

V. Devarapalli; R. Wakikawa; A. Petrescu; P. Thubert (January 2005).

3344: 3304: 3263: 3225: 3111: 3044: 2998: 2676: 2448: 2419: 2339: 2331: 2319: 1992: 1890: 1651: 1471: 1242: 945: 434: 328: 227: 207: 3071:"Privacy Extensions for Stateless Address Autoconfiguration in IPv6" 669:

responsibility for packet fragmentation in the end points. The IPv6

3728:

IPv6 Fundamentals: A Straightforward Approach to Understanding IPv6

2637:

Google IPv6 Conference 2008: What will the IPv6 Internet look like?

5183: 5032:

International Journal of Advanced Network, Monitoring and Controls

4717: 4594: 4562: 2527:(July 2017), "Internet Protocol, Version 6 (IPv6) Specification", 2224: 2103: 2011: 1934: 1926: 1827: 1814: 1643: 1516: 1391: 1219: 1178: 1127: 1084: 895: 735: 714: 637: 455: 233: 4646:

M. Cotton; L. Vegoda; B. Haberman (April 2013). R. Bonica (ed.).

3416:"Operational Implications of IPv6 Packets with Extension Headers" 4653: 4498:"Understanding Dual Stacking of IPv4 and IPv6 Unicast Addresses" 4358: 4077: 4034: 3419: 3296: 3255: 2269: 2054:

systems that do not have an IPv6 stack enabled by default, with

1967:. A previous format, called "IPv4-compatible IPv6 address", was 1907: 1784: 1646:, where the name space is hierarchically divided by the 1-digit 1567: 727: 662: 569: 418: 388: 338: 258: 223: 143: 5234: 3759:

IPv6 Address Planning: Designing an Address Plan for the Future

2880:"Technical Criteria for Choosing IP The Next Generation (IPng)" 1999:, this feature is controlled by the socket option IPV6_V6ONLY. 1570:"recommends giving home sites significantly more than a single 5314: 2343: 1654:

units (4 bits) of the IPv6 address. This scheme is defined in

1049:. IPv6 hosts are required to do one of the following: perform 762:

model, it became clear that this would not suffice to prevent

585: 243: 29: 4153:

IAB/IESG Recommendations on IPv6 Address Allocations to Sites

3370:(3rd ed.). Sebastopol, CA: O'Reilly Media. p. 196. 1983:

2000, XP, and Server 2003), or because of security concerns (

872:). Some blocks of this space and some specific addresses are 4531: 3585:

The Addition of Explicit Congestion Notification (ECN) to IP

3095:

F. Gont; S. Krishnan; T. Narten; R. Draves (February 2021).

2330:

ISPs had deployed IPv6 for the majority of their customers.

2249:

to allow for IPv6 deployment, which began in the mid-2000s.

1195:

extension header), the payload must be less than 4 GB.

2292: 2288: 5227:– RFC 8200 document ratifying IPv6 as an Internet Standard 4074:"IPv6 Stateless Address Autoconfiguration - Section 5.5.1" 2374:

on IPv6, with the two network providers refusing to peer.

2260:. By 2016, 82% of the traffic on their network used IPv6. 1819:

IPv6 Prefix Assignment mechanism with IANA, RIRs, and ISPs

1009:

Moreover, an IPv6 header does not include a checksum. The

3154:"Overview of the Advanced Networking Pack for Windows XP" 2597: 2595: 2593: 2591: 1665:

When a dual-stack host queries a DNS server to resolve a

1581:, but does not recommend that every home site be given a 1030:

or error detection in higher-layer protocols, namely the

967:

address) can be independently self-configured by a host.

5133:"Verizon Mandates IPv6 Support for Next-Gen Cell Phones" 4623: