AS1299

AS1299 is the global Tier-1 backbone of Arelion Sweden AB, a transit-free network that consistently ranks at or near the very top of the Internet's transit hierarchy. In the current CAIDA AS Rank it sits at #2 globally, with a customer cone of roughly 42,167 ASNs, ~839,207 prefixes, and ~1.77 billion addresses, and an AS degree around 2,596 (about 2,529 customers, 67 peers, and zero providers — the signature of a settlement-free Tier-1). The network markets itself as one of the world's largest IP backbones and is widely cited as carrying a very large share of global internet routes. It originates only a small block of its own address space (on the order of a few hundred thousand addresses) but announces the full table as transit, so an AS1299 hop almost always means "traffic crossed Arelion," not that the endpoint belongs to Arelion. The carrier-grade identity is reinforced by its peering posture: selective peering, RPKI route-origin validation, and rejection of RPKI-invalid routes from peers and customers. Because it is pure transit, abuse signals attach to downstream customers rather than to AS1299 itself.

Operator

Arelion Sweden AB (RIPE org se.twelve99) [Confirmed] — RIPE RDAP/WHOIS

Country / RIR

Sweden, RIPE [Confirmed] — RIPE RDAP

Allocated

~1993 original allocation (legacy; BGPView shows 1993-09-01); RIPE aut-num object dated 2002-09-19 [Confirmed range — note source discrepancy] — bgp.tools / bgpview

Org status

acquired & renamed — Telia Carrier divested to Polhem Infra (announced 2020-10-06; closed 2021-06-01, EV ~SEK 9,450M / ~US$1.055B); rebranded to Arelion 2022-01-19. Lineage: TeliaSonera Intl Carrier → Telia Carrier (2016) → Arelion (2022) — arelion.com, prnewswire.com

Security/abuse context

pure Tier-1 transit; abuse attaches to downstream customers, not Arelion. Operator runs RPKI ROV + DDoS mitigation. No notable public abuse signal attributable to the backbone as of 2026-06-04

Network & routing

Network type

transit-backbone (Tier-1, transit-free) [Confirmed] — CAIDA + PeeringDB

Size

CAIDA AS Rank #2 globally — customer cone ~42,167 ASNs / ~839,207 prefixes / ~1,770,655,445 addresses; AS degree ~2,596 (~2,529 customers, ~67 peers, 0 providers); ~119–150 IPv4 originated (~265,357 announced as transit), ~14–128 IPv6 — asrank.caida.org/asns/1299, bgp.he.net (2026-05/06)

Routing/peering

transit-free (0 upstreams); ~2,642 peers observed; selective peering; rejects RPKI-invalid; 100+ Tbps capacity — peeringdb.com/net/10

Notable usage

global Tier-1 IP transit backbone ("Twelve99", AS1299); markets itself as a top backbone powering a large share of internet routes — arelion.com

Related ASNs

"Twelve99" branding (twelve99.net references AS1299)

Analyst note

A transit AS — an IP rarely "belongs" to Arelion as an endpoint; it appears in AS paths as upstream. Its presence simply means the path crossed Arelion's backbone.