IPv4 address fatigue is depletion of an unallocated set of IPv4 addresses. Because there are less than 4.3 billion addresses available, depletion has been anticipated since the late 1980s, when the Internet began to experience dramatic growth. This depletion is one of the reasons for the development and deployment of its successor protocol, IPv6. Currently IPv4 and IPv6 live side by side on the Internet.
IP address space is managed globally by the Internet Assigned Numbers Authority (IANA), and by five regional Internet Registries (RIRs) responsible in the region assigned to assignments to end users and local Internet logging, such as Internet service providers. The key market forces that accelerate the decline in IPv4 addresses include an ever-growing number of Internet users, always on devices, and mobile devices.
The Internet Engineering Task Force (IETF) created the Routing and Addressing Group (ROAD) in November 1991 to respond to scalability issues caused by the classful network allocation system in place at the time. The anticipated scarcity has been a driving factor in creating and adopting several new technologies, including network address translation (NAT), Classless Inter-Domain Routing (CIDR) in 1993, and IPv6 in 1998. IPv6, the successor to IPv4 technology designed to overcome this problem, supporting about 3.4 ÃÆ' - 10 38 network addresses.
Although depletion estimates are approaching the final stages of 2008, most Internet service providers and software vendors have just started deploying IPv6.
Top-level fatigue occurred on January 31, 2011. Four of the five RIRs have spent allocations on all blocks they do not have for the IPv6 transition; this happened on April 15, 2011 for Asia-Pacific, on September 14, 2012 for Europe, on June 10, 2014 for Latin America and the Caribbean, and on September 24, 2015 for North America. Each ISP still has an unspecified IP address, and can recycle addresses that their customers no longer need. Every exhausted address pool is available at different times.
Video IPv4 address exhaustion
Penanganan IP
Each node of an Internet Protocol (IP) network, such as a computer, router, or network printer, is assigned the IP address used to locate and identify nodes in communication with other nodes on the network. Internet Protocol version 4 provides 2 32 (4,294,967,296) addresses. However, large blocks of IPv4 addresses are reserved for special use and are not available for public allocation.
More precisely, if the device has multiple network interfaces, then each interface must have at least one different IP address assigned to it. For example, a laptop may have a wireless network interface and a wired network interface using a network cable, and this will require a total of two IP addresses, one per interface. Another example is a phone with 3G network interface and interface to wireless LAN. All routers must have multiple network interfaces and will usually have multiple IP addresses associated with it. It may also be that an interface can be assigned more than one IP address for various reasons.
The IPv4 addressing structure provides an insufficient number of publicly accessible addresses to assign different addresses to each device or Internet service. This issue has been mitigated for some time by changes in address allocation and Internet routing infrastructure. The transition from classful networking addresses to Classless Inter-Domain Routing delays substantial address delays.
Additionally, network address translation (NAT) enables Internet and enterprise service providers to masquerade private network address space with only one publicly accessible IPv4 address on the Internet interface of the router where the customer is, instead of assigning public addresses to each network device. Things are tricky, unconscious NAT-IP devices undermine native IPv6 connectivity and 6to4, and a large number of 6in4 tunnel solves.
Maps IPv4 address exhaustion
Address Reduction
While the main reason for addressing IPv4 addresses is insufficient capacity in the design of the original Internet infrastructure, several additional drivers have worsened the shortcomings. Each of them increases the demand for limited supply of addresses, often in ways not anticipated by the original network designer.
- Mobile devices
- As IPv4 is becoming a de facto standard for networked digital communications and substantial cost of distributing computing power to hand-dropped devices, mobile phones have become viable Internet hosts. The new 4G device specification requires IPv6 addressing.
- The connection is always on
- Throughout the 1990s, the dominant mode of consumer Internet access was a dial-up telephone modem. The rapid increase in the number of dial-up networks increases the level of address consumption, although it is common that a collection of modems, and as a result, a set of specified IP addresses, is shared among large customer bases. In 2007, however, broadband Internet access began to exceed 50% penetration in many markets. Broadband connections are always on, because gateway devices (routers, broadband modems) are rarely turned off, so address uptake by Internet service providers continues at an accelerated pace.
- Internet demographics
- There are hundreds of millions of households in the developed world. In 1990, only a small portion had Internet connectivity. Only 15 years later, nearly half of them have persistent broadband connections. Many new Internet users in countries like China and India also overcome fatigue.
- Inefficient use of addresses
- Organizations that acquired IP addresses in 1980 often allocated far more addresses than they actually needed, because good initial network allocation methods were inadequate to reflect fair use. For example, large companies or universities are given a class A block of addresses with over 16 million IPv4 addresses each, because the next smaller allocation unit, class block B with 65,536 addresses, is too small for the intended placement.
- Many organizations continue to use public IP addresses for devices that are not accessible outside their local network. From a global address allocation point of view, this is not efficient in most cases, but there are scenarios where it is preferred in the organization's network implementation strategy.
- Due to inefficiency caused by subnetting, it is difficult to use all addresses in a block. Host-density ratio, as defined in RFC 3194, is a metric for utilizing IP address blocks, used in allocation policies.
Mitigation effort
Attempts to delay addressing room fatigue began with the recognition of problems in the early 1990s, and the introduction of a number of stop-gap removals to make existing structures operate more efficiently, such as classy networks, Classless Inter-Domain Routing (CIDR) methods, (NAT) and strict usage-based allocation policies. Other technologies include:
- the use of network address translation (NAT) that allows private networks to use a single public IP address and allow private addresses on a private network;
- the use of private network addressing;
- virtual name-based hosting from website;
- tighter control by the regional Internet registry on the allocation of addresses to the local Internet registry;
- network numbering and subnetting to recover large blocks of address space allocated in the early days of the Internet, when the Internet uses inefficient and efficient network addressing.
Date and impact of fatigue
On January 31, 2011, two final unbanked IANA/8 address blocks were allocated to APNIC in accordance with the RIR request procedure. This leaves five blocks reserved but unfilled/8. In accordance with ICANN policy, IANA continues to allocate one of the five/8 for each RIR, exhausting the IANA pool, at the ceremony and press conference on February 3, 2011.
Various legacy address blocks with administrative histories shared among RIRs are distributed to the RIR in February 2011.
APNIC is the first regional Internet Registry to run out of freely allocated IPv4 addresses on April 15, 2011. This date marks the point where not everyone who needs an IPv4 address can be allocated one. As a consequence of this fatigue, the end-to-end connectivity required by specialized applications will not be universally available on the Internet until IPv6 is fully implemented. However, IPv6 hosts can not directly communicate with IPv4 hosts, and must communicate using a dedicated gateway service. This means that general-purpose computers still need to have IPv4 access, for example via NAT64, in addition to the new IPv6 addresses, which more effort than just support IPv4 or IPv6. Demand for IPv6 is expected to be pervasive for three to four years.
In early 2011, only 16-26% of computers were capable of IPv6, while only 0.2% preferred IPv6 addresses with many using transition methods such as Teredo tunneling. Approximately 0.15% of the top millions of websites are accessed by IPv6 in 2011. Things are complicated, 0.027% to 0.12% of visitors can not reach dual-stack sites, but a larger percentage (0.27% ) can not reach IPv4 site only. IPv4 fatigue mitigation technologies include sharing IPv4 addresses to access IPv4 content, IPv6 dual-stack implementation, protocol translation to access IPv4 and IPv6 addressed content, and bridging and constructing tunnels to bypass a single protocol router. The early signs of IPv6 adoption that are accelerated after the IANA's expiration are clear.
Regional fatigue
All RIRs have set aside a small set of IP addresses for transition to IPv6 (eg carrier-class NAT), from which each LIR can usually get at most 1024 in total. ARIN and LACNIC have the last/10 backup for IPv6 transition. APNIC, and RIPE NCC have reserved the last block earned/8 for the IPv6 transition. AFRINIC provides block/11 for this purpose. When only this last block is left, the supply of IPv4 RIR addresses is said to "run out".
APNIC is the first RIR to limit the allocation of up to 1024 addresses for each member, as its group reaches the critical level of one/8 blocks on April 14, 2011. RIR APNIC is responsible for address allocation in the fastest Internet expansion areas, including emerging markets of China and India.
RIPE NCC, the regional Internet registry for Europe, is the second RIR to drain its address set on September 14, 2012.
On June 10, 2014, LACNIC, the regional Internet registry for Latin America and the Caribbean, is the third RIR to drain its address set.
ARIN is exhausted on September 24, 2015. ARIN has not been able to allocate many requests since July 2015, but smaller demands are still met. After IANA exhaustion, the IPv4 address space request becomes subject to additional restrictions in ARIN, and becomes tighter after reaching the last 8/8 of April 2014.
In April 2017, AFRINIC became the last Regional Internet Registry to descend into the last 8/8 block of IPv4 addresses (102/8), thus triggering the final phase of IPv4's depleted policy. According to Geoff Huston's projection, AFRINIC will reach the 11th block leaving a sign of fatigue in the first half of 2018.
The impact of APNIC RIR fatigue and fatigue LIR
Systems that require intercontinental connectivity will have to deal with the fatigue mitigation already due to APNIC fatigue. At APNIC, existing LIRs may apply to stocks twelve months before they run out when they use more than 80% of the allocated space allocated to them. Since April 15, 2011, the date when APNIC reaches the last block/8, each member (current or future) will only be able to get one 1024 address allocation (a/22 block) once. As the slope of the APNIC pool line on the "Geoff Huston projection of the evolution of the IP set for each RIR" to the right shows, the last block/8 will be emptied within a month without this policy. With APNIC policy, any current or future members may only receive one block/22 from the last/8 (there are 16384/22 blocks in the last/8th block). Because there are about 3000 APNIC members today, and about 300 new APNIC members every year, APNIC expects this last/8 block to last for years. Since redistribution of the recovered space, APNIC distributes additional/22 to each member on request.
1024 addresses in block/22 may be used by APNIC members to supply NAT44 or NAT64 as services on an IPv6 network. However on a new large ISP, 1024 IPv4 addresses may not be enough to provide IPv4 connectivity to all customers due to the limited number of available ports per IPv4 address.
Regional Internet Registries (RIRs) for Asia (APNIC) and North America have a policy called IPv4 Inter-RIR Transfer Policy, which allows IPv4 addresses to be transferred from North America to Asia. ARIN policy applied on July 31, 2012.
Business IPv4 brokers have been established to facilitate this transfer.
Very important attribution warning
Estimated complete IPv4 address completion times vary widely in the early 2000s. In 2003, Paul Wilson (director of APNIC) stated that, based on current deployment levels, the available space will last for a decade or two. In September 2005, a report by Cisco Systems suggested that the available set of addresses would be exhausted within 4 to 5 years. In the last year before exhaustion, IPv4 allocations are accelerating, leading to fatigue that tends to an earlier date.
- On May 21, 2007, the American Register for Internet Numbers (ARIN), the RIR for the US, Canada and a number of island countries (mostly in the Caribbean), advised the Internet community that, due to the expected fatigue in 2010, " IPv6 numbering resources are required for applications requiring continuous availability of ARIN from adjacent IP numbering resources ". "Applications" include general connectivity between devices on the Internet, as some devices only have IPv6 addresses allocated.
- On June 20, 2007, the Latin American Internet and Caribbean Registry (LACNIC) address, recommending "preparing a regional network for IPv6" by January 1, 2011, for IPv4 address depletion "within three years".
- On June 26, 2007, the Asia-Pacific Network Information Center (APNIC), the RIR for Pacific and Asia, endorsed a statement by the Japan Network Information Center (JPNIC) that to continue expanding and developing the Internet, moving towards an IPv6-based Internet is recommended. This, with a focus on fatigue expected around 2010, will create major restrictions on the Internet.
- On October 26, 2007, the RIPE NCC, the RIR for Europe, the Middle East, and parts of Central Asia, supports a statement by the RIPE community that urges "the expansion of IPv6 deployment into priority high by all stakeholders ".
- On April 15, 2009, ARIN sent a letter to all CEO/Executives of companies with IPv4 addresses allocated to inform them that ARIN expects IPv4 space to be exhausted within the next two years.
- In May 2009, RIPE NCC launched IPv6ActNow.org to help explain "IPv6 in the sense that everyone can understand and provide useful information aimed at promoting global adoption of IPv6."
- On August 25, 2009, ARIN announced a series of joint events in the Caribbean region to drive the adoption of IPv6. ARIN reports currently that fewer than 10.9% of the remaining IPv4 address space.
- World IPv6 Day is an event sponsored and hosted by the Internet Society and some major content providers to test the public IPv6 implementation. It starts at 00:00 UTC on June 8, 2011 and ends at 11:59 pm on the same day. This test mainly consists of websites that publish AAAA records, enabling IPv6 capable hosts to connect to these sites using IPv6, and for incorrectly configured networks for repair.
- World IPv6 Launch Day takes place on June 6, 2012, following the success of World IPv6 Day a year earlier. It involves more participants and has a more ambitious goal of permanently enabling IPv6 in participating organizational networks.
Post-exhaust mitigation
In 2008 policy planning for the final era of game and post-exhaustion is underway. Several proposals have been discussed to delay the shortage of IPv4 addresses:
Unused IPv4 space recall
Prior to and during the time when classful network designs were still used as allocation models, large blocks of IP addresses were allocated to multiple organizations. Due to the use of a Classless Inter-Domain (CIDR) Router, the Internet Assigned Numbers Authority (IANA) has the potential to regain these ranges and re-publish addresses in smaller blocks. ARIN, RIPE NCC, and APNIC have a transfer policy, so the address can be returned, for the purpose of transferring to a specified recipient. However, it can be costly in terms of cost and time to give new numbers a large network, so the organization is likely to object, with possible legal conflicts. However, even if all this is reclaimed, it will only result in delay in the address exhaustion date.
Similarly, IP address blocks have been allocated to non-existent entities and multiple blocks of IP addresses allocated or most of them never used. No strict IP address allocation calculation has been done, and will require significant effort to track which addresses are really not used, as many are only used on the intranet.
Some address space previously provided by IANA has been added to the available set. There is a proposal to use the IPv4 class IP address range (which will add 268.4 million IP addresses to the available pool) but many computers and operating systems routers and firmware do not allow the use of this address. For this reason, the proposal has sought not to designate class E space for public assignment, but instead proposes to allow private use for networks that require more address space than is currently available through RFC 1918.
Some organizations have returned a large block of IP addresses. In particular, Stanford University released their block of Class A IP addresses in 2000, making 16 million IP addresses available. Other organizations that have done so include the US Department of Defense, BBN Technologies, and Interop.
Market in IP address
The creation of a market for buying and selling IPv4 addresses has been considered a solution to the problem of IPv4 rarity and redistribution. The key benefit of the IPv4 address market is that it allows buyers to maintain uninterrupted local network functionality. IPv6 adoption, while in progress, is still in its infancy. This requires significant resource investment, and raises issues of non-compliance with IPv4, as well as certain security and stability risks.
- Marketplace creation in IPv4 addresses will only delay the tired execution of IPv4 address space for a relatively short time, as the public Internet is still expanding.
- The legal ownership concept of an IP address as a property is explicitly rejected by ARIN policy documents and RIPE NCC and by the ARIN Registration Service Agreement, even though ownership rights have been postulated based on a letter from the National Science Foundation General Counsel. The NSF then pointed out that the view was unofficial, and a statement from the Commerce Department was subsequently issued which indicated that "the USG participates in developing and supporting the policies, processes and procedures agreed by the Internet technical community through ARIN."
- Ad-hoc trading in addresses can lead to fragmented path patterns that can increase the size of global routing tables, potentially causing problems for routers with inadequate routing memory resources.
- Microsoft purchased 666,624 IPv4 addresses from Nortel's $ 7.5 million liquidation sale in a deal brokered by Addrex. Before exhaustion, Microsoft may obtain addresses from ARIN at no cost, as long as, in accordance with ARIN policy, Microsoft may present ARIN with the need for them. The success of this transfer depends on Microsoft who successfully brings ARIN with such justification. This purchase gives Microsoft sufficient supply to meet their growth needs over the next 12 months, not for the 3 month period as typically requested from ARIN.
Transition mechanism
Because IPv4 address pools spend it, some ISPs will not be able to provide a globally geared IPv4 address to customers. However, customers tend to require access to services on the IPv4 Internet. Several technologies have been developed to provide IPv4 services over an IPv6 access network.
In ISP-level IPv4 NAT, ISPs can implement IPv4 network address translation within their network and assign private IPv4 addresses to customers. This approach allows customers to keep using existing hardware. Some estimates for NAT argue that US ISPs have 5-10 times the amount of IP they need to serve existing customers. This has been successfully applied in some countries, for example, Russia, where many broadband providers use operator-class NATs, and offer general-purpose IPv4 addresses at an additional cost.
However the allocation of private IPv4 addresses to customers may conflict with private IP allocations on the customer's network. In addition, some ISPs may have to split their networks into subnets to allow them to reuse private IPv4 addresses, complicating network administration. There are also concerns that consumer level NAT features such as DMZ, STUN, UPnP and application-level gateways may not be available at the ISP level. The ISP NAT level can generate multi-level address translations that are likely to complicate the use of technologies such as port forwarding used to run Internet servers in private networks.
NAT64 translates IPv6 requests from clients to IPv4 requests. This avoids the need to provide IPv4 addresses to clients and allows clients that only support IPv6 to access IPv4 resources. However this approach requires DNS servers with DNS64 capabilities and can not support IPv4-only client devices.
DS-Lite (Dual-Stack Light) uses tunnels from the equipment where the customer to the network address translator at the ISP. The equipment where consumers encapsulate IPv4 packets in IPv6 packets and send them to a host known as AFTR element. The AFTR element outlines the packets and does the network address translation before sending it to the public Internet. NAT in AFTR uses the client IPv6 address in its NAT mapping table. This means that different clients can use the same private IPv4 address, thus avoiding the need to allocate private IPv4 IP addresses to customers or using multiple NATs.
Deployment of IPv6 is a standards-based solution for IPv4 address shortages. IPv6 is supported and implemented by all Internet technical standards bodies and network equipment vendors. This includes many design improvements, including the replacement of 32-bit IPv4 address formats with 128-bit addresses that provide unlimited addressing space for the future. IPv6 has been in active production deployment since June 2006, following testing and evaluation worldwide in the 6bone stop project. Interoperability for hosts using only the IPv4 protocol is implemented with various IPv6 transition mechanisms.
See also
- List assigned/8 IPv4 address blocks
- 512K Day - an event in 2014, involving fatigue of the default routing hardware routing slot on multiple routers
References
External links
- The current official status of IPv4/8 allocations, such as those maintained by IANA
- ICANN restores Large Block Internet Addresses (14.0.0.0/8) 2008-02-10
- Global Policy Proposal for IPv4 Address Space Remaining - Background Report 2008-09-08
- potaroo.net: Report IPv4 Address with countdown
- IPv4 RIR Status: RIPE APNIC
- Daniel J. Bernstein's IPvirruption article on issues affecting the ipv4-to-IPv6 transition
Source of the article : Wikipedia
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