AS159

AS159 is a low-numbered, legacy Autonomous System Number registered through ARIN to The Ohio State University (OSU) in Columbus, Ohio, where it serves as the campus backbone for one of the largest public research universities in the United States. It carries academic, research, and administrative traffic for the main Columbus campus and the regional campuses (Lima, Marion, Mansfield, Newark, Wooster). In BGP terms AS159 is a small stub / end-site network: it originates a handful of prefixes and provides no transit. Routing aggregators agree it announces about 7 IPv4 prefixes — including three legacy /16 blocks (128.146.0.0/16, 140.254.0.0/16, 164.107.0.0/16) totalling roughly 198,400 addresses — plus a single IPv6 /48 (2620:0:1a10::/48). Its two BGP neighbors are both OARnet (the Ohio Academic Resources Network) ASNs: AS600 as the primary full-IPv4/IPv6 upstream and AS3112 as an IPv4-only secondary, so OSU reaches Internet2 and the commercial Internet entirely through OARnet rather than via direct IXP membership. Despite the small prefix count, RIPE RIS shows strong global visibility (300+ peers observing the announcements; first prefix seen 2000-08-18). The registrant org handle is OSU-2-Z and the abuse contact is abuse@osu.edu. As of June 2026 no public blocklist, abuse feed, or NANOG thread flags AS159 as a source of spam, scanning, or malicious traffic; the one notable security event on record (a 2023 server breach exposing about 760,000 records) made OSU a breach victim, not an abuse originator. bgp.he.net carries a possible-bogon flag and shows no valid ROAs for the ASN, both noted below as single-source and unconfirmed.

Operator

The Ohio State University — OCIO Enterprise Networking, 320 West 8th Avenue (registrant) / 1050 Carmack Road (POC), Columbus, OH 43201 (ARIN org handle OSU-2-Z) [Confirmed] — rdap.arin.net/registry/autnum/159

AS name

reported as OSUNET-AS by routing aggregators; the ARIN RDAP autnum payload shows only the registrant org vcard "Ohio State University" (no distinct ASName field surfaced), so OSUNET-AS is aggregator-sourced rather than RDAP-confirmed [Likely] — ipinfo.io/AS159, ip2location.com/as159

Country / RIR

US, ARIN [Confirmed] — rdap.arin.net/registry/autnum/159

Allocated

1988-02-19 — ARIN autnum top-level registration event (last changed 2023-02-02); NOT an IEEE assignment date (IEEE publishes no ASN registration dates) [Confirmed] — rdap.arin.net/registry/autnum/159

Org status

active holder — public state research university (land/sea/space-grant institution); clean WHOIS resolution to OSU OCIO [Confirmed] — rdap.arin.net/registry/autnum/159

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal as of 2026-06-16 — not on Spamhaus SBL/DROP/ASN-DROP, no AS-level AbuseIPDB/GreyNoise findings, no relevant NANOG threads. OSU disclosed a 2023 server breach exposing ~760,000 records (victim, not abuse source); a May 2026 Canvas/Instructure incident was a third-party vendor event, not an AS159 routing-layer issue

Network & routing

Network type

education / academic — public research university campus network; BGP-classified as a stub / eyeball end-site that provides no transit [Confirmed] — bgp.tools/as/159, ipinfo.io/AS159

Size

~7 IPv4 prefixes (~198,400 addresses; ~775 /24 equivalents) incl. legacy /16s 128.146.0.0/16, 140.254.0.0/16, 164.107.0.0/16; 1 IPv6 /48 (2620:0:1a10::/48) [Confirmed] — bgp.he.net/AS159, bgp.tools/as/159

Routing/peering

exactly 2 BGP neighbors, both OARnet — AS600 (primary, IPv4+IPv6) and AS3112 (secondary, IPv4 only); no downstream customers / effectively zero customer cone. OARnet (AS600) in turn transits via Lumen/Level 3 (AS3356), AT&T (AS7018), Internet2 (AS11164), and Hurricane Electric (AS6939)

[Confirmed] — bgp.he.net/AS159, stat.ripe.net asn-neighbours

IX presence

none confirmed for AS159 directly (PeeringDB returns 404 for /asn/159; no IXP membership listed by bgp.he.net or bgp.tools); typical for a university that reaches exchanges through OARnet [Unknown] — peeringdb.com (404), bgp.he.net/AS159

RPKI

no valid RPKI origins recorded at bgp.he.net; ROA coverage not confirmed / likely absent (single-source) [Likely] — bgp.he.net/AS159

Routing visibility

~327 IPv4 and ~320 IPv6 RIS peers observing announcements; first prefix seen 2000-08-18 [Confirmed] — stat.ripe.net routing-status

Notable usage

campus backbone for The Ohio State University; reaches Internet2 and the commercial Internet via OARnet. OSU was among the early Ohio institutions in the Internet2 effort [Confirmed] — ipinfo.io/AS159, oar.net

Bogon flag

bgp.he.net flags AS159 as possibly announcing a bogon; specific prefix not identified and not corroborated by a second source [Likely] — bgp.he.net/AS159

Technical / abuse contacts

technical/admin POC ZT31-ARIN (network@osu.edu, hostmaster@osu.edu, +1-614-688-4357), marked validated; abuse POC NAC29-ARIN (abuse@osu.edu, +1-614-688-4357), flagged by ARIN as Unvalidated (no response since 2025-09-18) [Confirmed] — rdap.arin.net/registry/autnum/159

Related networks

OARnet / AS600 (Ohio statewide academic fiber network, OSU's upstream); Ohio Supercomputer Center; Internet2 [Confirmed] — oar.net, en.wikipedia.org/wiki/OARnet

Analyst note

stable, legitimate, well-maintained academic stub network. Absence of NANOG/Reddit/PeeringDB corroboration is normal for institutional networks and is recorded as Unknown rather than treated as a negative signal. The OSU-2-Z org handle (from the RDAP payload) supersedes the "OSU-4" value seen in one secondary source.