Who owns Indonesia's IPv4 address space?

Indonesia has 18,339,840 IPv4 addresses. That is 1.09 /8s, or 64 addresses for every 1,000 people. They sit in 6,304 separate registry blocks, delegated since 1988, and the distribution is far more lopsided than the total suggests: one company holds 31.6% of them, three companies hold 66%, and a single /10 handed to Telkomsel in April 2011 accounts for 22.9% of the national total on its own.

This post takes APNIC’s delegation snapshot apart to answer three questions: who holds Indonesia’s IPv4, how the space is distributed, and what the shape of it says about how the country got online.

Where the numbers come from

APNIC publishes a daily machine-readable snapshot of every resource it has delegated: delegated-apnic-latest. Filtering the 29 October 2026 file for cc = ID and type = ipv4 gives 6,304 records and 18,339,840 addresses. To turn contact handles into organisations, every block was then looked up in APNIC’s RDAP service and grouped by its registrant or administrative contact — 6,304 lookups, because the delegation file carries no names.

Three limits belong up front.

This is registry data, not traffic data. A record says who a block is registered to, not who routes it, not where it is used, and not how full it is. The two views diverge more than you would expect, and the divergences are the interesting part.

Holdings move. Blocks are transferred and re-registered, and mergers only show up when a record changes. XL Axiata, Smartfren and Smart Telecom became XLSmart in April 2025, so they are counted as one holder here even though their blocks still carry separate records.

IDNIC is a pool, not a company. Indonesia runs a National Internet Registry under APJII that receives space from APNIC and sub-delegates it to members. It looks like the fifth-largest holder at 4.0%, but its 741,632 addresses are spread over 1,554 records belonging to roughly 1,500 small ISPs and end users.

Indonesia in the region

Indonesia is the eighth-largest holder in APNIC — behind China, Japan, Korea, Australia, India, Taiwan and Singapore — and second in ASEAN. Singapore’s 28.75M addresses are 57% more than Indonesia’s, for a population of 6.1M: 4,704 addresses per 1,000 people against Indonesia’s 64. Vietnam, with a third of Indonesia’s population, holds 16.50M (162 per 1,000). Malaysia and Thailand both hold less than half of Indonesia’s total but two to three times as much per person.

Some of that is early-mover advantage in a registry that handed out space generously to whoever asked first, and some of it is Singapore’s role as a regional hosting and headquarters location. Either way, Indonesia’s number is the one that matters for the country’s own network: 285 million people, 64 addresses each, and a mobile-first Internet.

Who holds the space

Telkomsel’s 5.79M addresses come from just eight blocks. One of them, 39.192.0.0/10 delegated on 12 April 2011, is 4,194,304 addresses — 22.9% of everything Indonesia holds. Telkom’s 4.18M is spread over 22 blocks, mostly /14s and /15s named TLKM_BB_INF_* and TLKM_BB_SERVICE_*, which is what a national broadband build-out looks like from the registry’s side. Indosat’s 2.15M still rests on two /12s it received on the same day in April 2008.

Add the incumbent to its mobile subsidiary and the Telkom group holds 54.4% of Indonesia’s IPv4 space. Then the curve falls off a cliff. The fourth-largest holder is First Media / Link Net with 833k; fifth is IDNIC’s pool of small ISPs; and the next company after them, XLSmart, has 206k — 1.1% of the country.

Five blocks are half the country

Those five delegations hold 9,437,184 addresses, or 51.5% of Indonesia’s total. All five were made between April 2008 and April 2011. Everything delegated before 15 April 2011 — 805 blocks — carries 84.5% of the space; the 5,499 blocks delegated since carry the other 15.5%.

That date is not arbitrary. On 15 April 2011, APNIC became the first regional registry to reach its final /8, and the rules changed overnight: no more large allocations — at most a /22 per member from the last remaining block, 103.0.0.0/8, a maximum APNIC cut to a /23 in 2019. Indonesia’s address space was effectively decided before lunch that day.

The shape: a fat head and a very long tail

The median delegation in Indonesia is a /23 — 512 addresses. 4,879 of the 6,304 blocks are /23 or smaller, and together they hold 10.9% of the space. Five blocks of /10 or larger hold 51.5%.

The registry’s status field splits the same data a second way. 3,359 records are allocated — space given to an ISP or organisation to manage — and they carry 17.06M addresses, 93% of the total. The other 2,945 records are assigned, meaning end-user assignments, and they carry 1.28M addresses at an average of 433 each. A /23 per campus, per government office, per company: that is what nearly half of Indonesia’s IPv4 delegations actually are.

The 2011 cliff

In 2011 alone Indonesia received 7.10M addresses in 164 blocks — 38.7% of everything it holds today, in a single year. Nothing before or since comes close: 2008–2010 averaged 1.9M a year, and every year after 2011 has been under 300k.

The bottom panel tells the rest of the story. Block counts kept climbing long after block sizes collapsed, because post-2011 growth happens in small slices. 4,030 of Indonesia’s 6,304 blocks — 64% of all delegations — sit inside 103.0.0.0/8, APNIC’s final /8. They hold 2.17M addresses, 11.8% of the total. The final /8 became the small-ISP registry: 2,155 blocks of /23 and 1,145 of /24, handed to operators you have probably never heard of.

The policy shows up in the record sizes. The 103/8 pool began with a maximum of one /22 per member; in 2019 APNIC cut that to a /23. Indonesia’s records switch over almost exactly: 188 blocks of /22 in 2018, 33 in 2019, none since 2020 — while /23 delegations rose from 52 in 2018 to 501 in 2022.

The final /8 is spent. Since 2024 the only new Indonesian entries inside 103/8 are reassignments within IDNIC’s existing blocks; everything new arrives from other pools — 43/8, 45/8, 157/8, 160–165/8 — in /23s and /24s. New delegations peaked at 666 blocks in 2022 and have fallen since: 581 in 2023, 461 in 2024, 316 in 2025, 318 in the first ten months of 2026. IPv4 growth in Indonesia is now a rounding error against the installed base.

What the space is for

Mobile network operators hold 44.6% of Indonesia’s IPv4: Telkomsel 31.6%, Indosat 11.7%, XLSmart 1.1%, Hutchison 3 Indonesia 0.1%. Telkom holds another 22.8%. Fixed broadband challengers (First Media, Biznet, MyRepublic) hold 5.7%, wholesale and datacenter operators 3.7%, and the IDNIC pool 4.0%.

Two details are worth pausing on.

XLSmart is the outlier. The merged XL Axiata + Smartfren serves tens of millions of subscribers but appears in the registry with 205,824 addresses — 1.1% of the country, or roughly one address per 300 subscribers. That gap is carrier-grade NAT: most of those subscribers never get a public IPv4 address of their own. Telkomsel, holding 5.79M addresses, is closer to one per 28. The registry measures who owns space, not who has users.

Education got in first. Universitas Indonesia holds 152.118.0.0/16 (August 1991) and ITB holds 167.205.0.0/16 (September 1993) — /16s bigger than what any Indonesian ISP can get today, handed out when the entire country had a handful of networks. Kemendikbud’s Jardiknas network holds 118.98.128.0/17 from 2007.

The lease market has arrived. IPXO, an IPv4 leasing broker, holds 47,104 addresses in the Indonesian registry — enough for the top 20. When a broker shows up in a national allocation table, addresses have become an asset class.

The other protocol

IPv4’s shape in Indonesia is fixed, so the growth is elsewhere. APNIC has made 2,825 IPv6 delegations to Indonesia, and 2,731 of them — 97% — came after 2011. The two largest, 2001:448a::/31 for Telkom and 2407:2::/31 for Indosat, are each 2⁹⁷ addresses: more space in one line than the entire IPv4 Internet, handed to the same two names that top the IPv4 table.

That is the real answer to Indonesian address scarcity. The 2011 cliff did not stop the Internet from growing; it just moved the growth to a protocol where nobody has to count.

Reproducing this

curl -sO https://ftp.apnic.net/stats/apnic/delegated-apnic-latest

# Indonesia: blocks and addresses
awk -F'|' '$2=="ID" && $3=="ipv4" { n++; a+=$5 }
          END { printf "%d blocks, %d addresses\n", n, a }' delegated-apnic-latest
# 6304 blocks, 18339840 addresses

# who a block belongs to
curl -s https://rdap.apnic.net/ip/39.192.0.0 | jq '.name, .entities[].vcardArray'

The delegation file is refreshed daily, so the absolute numbers drift by a few hundred addresses a month; the shape does not. Everything in this post is a snapshot of 29 October 2026.