IPv6 Address Distribution Plan of IANA
What are the roles of RIR, NIR and LIR? Explain how IANA manages IPV6.
How is internet governed? Discuss the role of IANA in regulation of the internet. Explain the IPv6 Address distrubution plan of IANA.
Example: How IPv6 Distribution Works
Imagine an ISP wants IPv6 addresses to serve its customers. It calculates the number of addresses it needs based on user count or network size and requests a block from its LIR. The LIR then assigns a portion of the IPv6 block it received from the RIR (or NIR, if applicable). Meanwhile, other LIRs in the same region allocate addresses to their own ISPs, all from blocks originally assigned by the same RIR from IANA.
This system ensures every IPv6 address is globally unique, properly routed, and scalable. Multiple ISPs in the same country or region can receive IPv6 blocks without conflicts, while remaining connected to the global Internet.
1. How IANA Distributes IPv6
IANA sits at the very top of the IPv6 hierarchy. It doesn’t give addresses directly to me or my ISP in Nepal. Instead, it hands out large blocks of IPv6 addresses to Regional Internet Registries. That way, every RIR has globally unique addresses to manage. This top-down approach keeps the Internet organized, prevents conflicts, and makes sure networks around the world, including ours in Nepal, can communicate reliably.
2. Regional Internet Registries (RIRs)
For Nepal, APNIC handles the Asia Pacific region. APNIC receives IPv6 blocks from IANA and passes smaller blocks to National and Local Internet Registries. RIRs also maintain important services like Whois directories, routing registries, and reverse DNS. They provide guidance and training so ISPs and organizations understand IPv6 distribution. Without RIRs, there would be no coordinated way to make sure addresses stay unique and usable.
3. National Internet Registries (NIRs)
NIRs manage IPv6 allocation at the country level. They operate under RIRs and make sure allocations follow both local and global rules. In the Asia Pacific region, NIRs like APJII in Indonesia or CNNIC in China handle national allocations. For Nepal, there is no national registry, so APNIC handles IPv6 distribution directly to LIRs and ISPs here. NIRs normally maintain national databases, coordinate with local ISPs, and ensure addresses are properly routed.
4. Local Internet Registries (LIRs)
LIRs get IPv6 blocks from RIRs or NIRs. In Nepal, local ISPs act as LIRs. They assign addresses to their customers, manage routing, and make sure their allocations follow APNIC policies. LIRs connect the higher-level registries with the end users, so when I get online at home, my address comes from the LIR’s allocation. This setup keeps everything scalable and organized.
5. Internet Service Providers (ISPs)
ISPs are the ones connecting me and other users in Nepal to the Internet. My ISP requests IPv6 addresses from its LIR, then assigns them to individual users. Hosting ISPs provide server space and bandwidth for businesses, while transit ISPs handle large-scale traffic between networks. Without ISPs, none of the IPv6 addresses assigned by IANA, APNIC, or LIRs would reach me. Together, they make sure every device in Nepal can communicate globally without conflicts.
Example: How IPv6 Reaches Me
If my ISP wants IPv6 addresses for all its customers in Nepal, it first estimates how many addresses it needs. Then it requests a block from its LIR. The LIR assigns a portion of the IPv6 block it received from APNIC. Other ISPs in Nepal do the same. Every ISP gets its block from the same hierarchy, all originally coming from IANA. This ensures addresses are globally unique, properly routed, and scalable. I can browse websites, use streaming services, and communicate online without any issues. Imagine your ISP in Nepal wants IPv6 addresses for all its customers. It first calculates the number of addresses it needs based on user count or network size. Then it requests a block from its LIR. The LIR takes a portion of the IPv6 block it received from the RIR or NIR, depending on the setup. Other LIRs in the same region do the same for their ISPs. All of these addresses originally come from IANA, ensuring every IPv6 address is globally unique, properly routed, and scalable. Multiple ISPs in the same country or region can receive blocks without conflicts, while staying connected to the global Internet.
a. Allocation Principles
IANA uses clear principles when giving IPv6 blocks to RIRs. The minimum allocation to an RIR is a /12 block. This gives RIRs enough address space to handle registrations for at least 18 months. Each RIR can then use its own strategies to allocate and reserve addresses efficiently for its region. This flexibility helps RIRs manage IPv6 space based on local demand while keeping global uniqueness intact.
b. Initial Allocations
When this policy was first introduced, any RIR that had less than a /12 block of unallocated IPv6 addresses received a full /12 allocation. This ensured that every RIR had enough space to start assigning addresses to NIRs, LIRs, and ISPs without delay.
c. Additional Allocations
RIRs can request more IPv6 address space when needed. Two main conditions trigger additional allocations. First, if an RIR’s available space drops below 50% of a /12. Second, if its available space is less than the estimated necessary space for the next nine months. In either case, IANA provides a single allocation large enough to meet the RIR’s needs for an 18-month period.
I. Calculation of Available Space
Available space is the number of currently free addresses plus any reservations expiring in the next three months, minus fragmented space. Fragmented space is any blocks smaller than the RIR’s minimum allocation size that cannot be efficiently used.
II. Calculation of Necessary Space
Necessary space is calculated based on demand. If the RIR does not report any special requirements, it is determined by multiplying the average number of addresses allocated per month over the past six months by the length of the upcoming period in months. This ensures RIRs always have enough IPv6 addresses to meet projected demand without over-allocating.