1. Where Do We Go From Here? John Curran ARIN President & CEO
This presentation describes the impending depletion of Internet Protocol version 4 (IPv4) and the importance of adopting the next version of the Internet Protocol, Internet Protocol version 6 (IPv6). This issue impacts everyone and must be understood and acted upon to ensure the continued growth and operation of the Internet.

2. Quick History of the Internet Protocol
Internet Protocol version 4 (IPv4, or just “IP”)
First developed for the original Internet (ARPANET) in spring 1978
Deployed globally with growth of the Internet
Total of 4 billion IP addresses available
Well entrenched and used by every ISP and hosting company to connect customers to the Internet
Allocated based on documented need
Internet Protocol version 6 (IPv6)
Design started in 1993 when IETF forecasts showed IPv4 depletion between 2010 and 2017
Completed, tested, and available for production since 1999
Total of 340,282,366,920,938,463,463,374,607,431,768,211,456 IP addresses available
Used and managed similar to IPv4
IPv6 provides a much larger pool of IP addresses. IPv6 is not backwards compatible with IPv4. The much larger IPv6 numbering system is meant to one day completely replace IPv4, but this will take many years. In the meantime, much of the Internet will run IPv4 and IPv6 simultaneously. This is necessary to ensure all users, regardless of the protocol version they are using, will be able to interact with all content on the Internet.

3. About IPv4 and IPv6 IP version IPv4 IPv6 Deployed 1981 1999
Address Size
32-bit number
128-bit number
Address Format
Dotted Decimal Notation:
Hexadecimal Notation: 2001:0DB8:0234:AB00: 0123:4567:8901:ABCD
Number of Addresses
232 = 4,294,967,296
2128 = 340,282,366,920,938,463,
463,374,607,431,768,211,456
Examples of Prefix Notation
/24
10/8
(a “/8” block = 1/256th of total IPv4 address space = 224 = 16,777,216 addresses)
2001:0DB8:0234::/48
2600:0000::/12
IPv4 address space has been used for decades to grow the Internet. When engineers deployed IPv4 in 1981, four billion IP addresses seemed like plenty. As the world caught on to the commercial possibilities of the Internet, though, engineers realized that the number of IP addresses simply wasn’t enough for all the laptops, mobile devices, web servers, routers, and other devices coming online. The first allocation of IPv6 address space by a Regional Internet Registry (RIR) to a provider was made in April of 1999. 3

4. IPv4 Address Space Utilization
The five RIRs each get IPv4 address space from the Internet Assigned Numbers Authority (IANA). The RIRs then use that IPv4 address space to satisfy requests for the resource in their respective regions. This slide indicates what has already been allocated to the RIRs, what is still available to the RIRs in the coming year(s), and what is unavailable. The unavailable address space includes Class D multicast address space, Class E experimental address space, and the address space identified in RFC 1918.
*as of 18 October 2010

5. Available IPv4 Space in /8s
IANA distributed forty /8s to the RIRs over the last four years. Due to anticipated increase in demand, RIRs will likely deplete the IPv4 address pool by the end of 2011.
In 2010, RIRs have been allocated fourteen /8 blocks as of 18 October, leaving twelve /8s unallocated (12/256 = 4.69%).

6. IPv4 Demand – RIR Allocations
This slide shows the number of /8s the IANA allocated to the RIRs each year. Each RIR holds approximately months of inventory. Allocation rates from these inventories and the need for several RIRs to request additional /8s in a close timeframe may cause a spike in allocations from the IANA to the RIRs.
In 2010, RIRs have been allocated fourteen /8 blocks as of 18 October.

7. IPv4 Depletion Situation Report
The RIRs have needed between 8 and 12 /8s each year worldwide.
There are 12 /8s remaining in the available pool as of 18 October 2010.
Demand for IPv4 continues to grow from organizations around the world.
With anticipated increase in demand for IPv4 address space, the IANA free pool will likely be depleted in The RIRs would then only be left with their respective resource inventories that will likely be quickly depleted.

8. IPv4 & IPv6 - The Bottom Line
We’re running out of IPv4 address space.
IPv6 must be adopted for continued Internet growth.
IPv6 is not backwards compatible with IPv4.
We must maintain IPv4 and IPv6 simultaneously for many years.
IPv6 deployment has begun.
IPv6 provides a much larger pool of IP addresses. IPv6 is not backwards compatible with IPv4. The much larger IPv6 numbering system is meant to one day completely replace IPv4, but this will take many years. In the meantime, much of the Internet will run IPv4 and IPv6 simultaneously. This is necessary to ensure all users, regardless of the protocol version they are using, will be able to interact with all content on the Internet.

9. IPv6 Deployment has begun
RIRs have been allocating IPv6 address space since 1999.
Thousands of organizations have received an IPv6 allocation to date.
ARIN has IPv6 distribution policies for service providers, community networks, and end-user organizations.
The RIRs began distributing IPv6 address space in Although thousands of organizations have obtained IPv6 resources to date, IPv6 has not been widely adopted. Some people predicted in the 1990s that the only true driver for IPv6 adoption would be the depletion of the IPv4 resource. Many people would agree those assessments were accurate, as today we see increased energy to adopt IPv6 in anticipation of imminent IPv4 depletion.

10. IPv4 & IPv6 Coexistence
Today, the Internet is predominantly based on IPv4.
For the foreseeable future, the Internet must run both IP versions (IPv4 & IPv6) at the same time. (When done on a single device, this is called the “dual-stack” approach.)
Deployment is already underway. Today, there are organizations attempting to reach your mail, web, and application servers via IPv6...
To ensure your web and mail servers are able to communicate with all users, regardless of the protocol version they are using, you must make them available over both IPv4 and IPv6. As the IPv4 free pool is depleted, many service providers will begin adding users to the Internet using IPv6. The already-deployed IPv4 base will remain with us for many years, however. It is important to support both versions of the protocol for many years to come.

11. Action Plans What does this mean for: Broadband Access Providers?
Internet Service Providers?
Internet Content Providers?
Enterprise Customers?
Equipment Vendors?
Government Organizations?
Building new networks and adding new users to the Internet require contiguous number resources. As we move closer to the depletion of the IPv4 resource, there will soon only be contiguous IPv6 resources available for new networks and users. This impacts everyone, but in slightly different ways. It is up to all of us to make this transition to a dual-stacked Internet as transparent as possible to home users. There is a fair amount of work involved to make this happen. It is important it does happen to ensure the smooth operation of the Internet we all enjoy today.

12. Call to Action
Your customers want access to the entire Internet, and this means IPv4 and IPv6 websites. Offering full access requires running IPv4/IPv6 transition services and is a significant engineering project.
Multiple transition technologies are available, and each provider needs to make its own architectural decisions.
In addition to provisioning new customers using IPv6, there is work to be done by Internet Service Providers to ensure their existing IPv4 customers are able to interact with new IPv6-only content on the Internet. ISPs must establish protocol translation and/or tunneling services for their customers. You should be planning this now.

13. Call to Action
Plan out how to connect businesses via IPv6-only and IPv4/IPv6 in addition to IPv4-only.
Businesses are beginning to ask for IPv6 over their existing Internet connections and for their co-located servers.
Communicate with your peers and vendors about IPv6, and confirm their timelines for production IPv6 services.
In addition to provisioning new customers using IPv6, there is work to be done by Internet Service Providers to ensure their existing IPv4 customers are able to interact with new IPv6-only content on the Internet. ISPs must establish protocol translation and/or tunneling services for their customers. You should be planning this now.

14. Call to Action Content must be reachable to newer Internet customers.
Content served only via IPv4 will be accessed by IPv6 customers via transition solutions run by access providers.
Plan on serving content via IPv6 in addition to IPv4 as soon as possible.
Content providers must begin upgrading their capabilities to include IPv6 access to services for their customers. Demand from customers may be low today, but soon they will begin contacting you to determine why people can’t see their website or send them . It is important to act now and ensure services over both IPv4 and IPv6.

15. Call to Action
Mail, web, and application servers must be reachable via IPv6 in addition to IPv4.
Open a dialogue with your Internet Service Provider about providing IPv6 services.
Each organization must decide on timelines, and investment level will vary.
Nearly all enterprise organizations rely on the Internet for at least part of their core operations and services. To ensure these services can communicate with everyone on the Internet going forward, your network infrastructure must be dual-stacked. Doing this now will ensure all users will continue to be able to see your website, use your web-based services, and communicate with you via . You may manage these services internally or through a vendor. Either way, speak to those who are responsible for your network operations about adding IPv6 accessibility to them.

16. Call to Action There was probably limited demand for IPv6 in the past.
Demand for IPv6 support will become mandatory very, very quickly.
Introduce IPv6 support into your product cycle as soon as possible.
Equipment vendors who distribute a hardware or software product that interacts with IPv4 networks should be making sure it is also capable of interacting with IPv6. Although customer demand for IPv6 support may have been limited in the past, it will very quickly escalate. To be prepared for customer demand, begin introducing IPv6 support into your product cycle as soon as possible.

17. Call to Action
Coordinate with industry to support and promote awareness and educational activities.
Adopt regulatory and economic incentives to encourage IPv6 adoption.
Require IPv6 compatibility in procurement procedures.
Officially adopt IPv6 within your government agencies.
Governments should use this time to promote IPv6 awareness. Coordinating with industry, creating incentives, and promoting IPv6 adoption are all very important and helpful ways for governments to assist with the transition to a dual-stacked Internet. Officially adopting IPv6 and making government services available over both versions of the Internet Protocol sends a very strong message and ensures services remain available to all.

18. IPv6 Adoption Needs IPv6 address space
IPv6 connectivity (native or tunneled)
Operating systems, software, and network management tool upgrades
Router, firewall, and other hardware upgrades
IT staff and customer service training
Organizations will need IPv6 address space to dual-stack their services. IPv6 address space is available either directly from an RIR or from an Internet Service Provider. To connect to the IPv6 portions of the Internet, you will need to get connectivity natively from your service provider, or through another organization that provides IPv6 tunneling services. It is important going forward to make IPv6 support a consideration when making any new purchases of network equipment and software. To upgrade your services to support both IPv4 and IPv6 you may need to acquire new equipment or update what you currently have with firmware updates. It is important your IT staff be trained to support IPv6. Many will be able to self-train using already available resources, however formal training is available through training vendors if needed.

19. Resources Community Use Slide Deck IPv6 Wiki
Information Page at
Outreach Microsite:
Social Media at ARIN
ARIN Board Resolution
Letter to CEOs
ARIN hosts a resource center devoted to IPv4 and IPv6 issues. Visit IPv4 / IPv6: The Bottom Line at for information including statistics sheets, this slide deck, the 2007 ARIN Board Resolution on IPv4 depletion, the letter ARIN sent to corporate CEOs advising them of the IPv4 depletion issue, how to find ARIN on social media networks including Facebook, Twitter, and YouTube, and other resources.
ARIN’s site is a wiki to facilitate IPv6 adoption discussions. Anyone is welcome to use the wiki. Many people have shared their IPv6 adoption information on the site and there are useful links and other resources available. Please share your adoption experiences by posting to the wiki.
In May of 2007 the ARIN Board of Trustees issued a resolution advising the Internet community on IPv6 adoption. The advisory recognizes the imminent depletion of IPv4 resources and advises organizations to adopt IPv6.
In April of 2009 the ARIN Board of Trustees directed ARIN staff to send a letter via certified mail to the CEO of every organization currently holding an IPv4 registration in the ARIN region. The purpose of this effort is to raise executive awareness of the depletion of IPv4 resources and to encourage the active adoption of IPv6. The letter also serves as notification that, in response to the approaching depletion of the IPv4 free address pool, the Board has directed ARIN staff to take additional steps to ensure the legitimacy of all IPv4 address space requests. ARIN now requires that all applications for IPv4 address space include an attestation of accuracy from an officer of the organization.

20. Learn More and Get Involved
Learn more about IPv6
Get Involved in ARIN
Public Policy Mailing List
Attend a Meeting
You can become involved in the ARIN processes to ensure your Internet number resource needs are met and the entire community benefits from your important participation. Information is available at the provided links.

21. Thank You
Please contact with any questions, comments, or suggestions.