AS178

AS178 is a legacy Autonomous System Number registered under ARIN to the Regents of the University of Michigan (commonly: University of Michigan), the public research university in Ann Arbor, Michigan founded in 1817. The ARIN registry record gives the AS name UMICH-AS-2 and an ASN registration date of April 28, 1988, placing it among the early-Internet allocations and reflecting the university's role as a founding participant in the development of academic networking. The key triage point is that AS178 is currently inactive: both bgp.he.net and bgp.tools independently show it originating zero IPv4 prefixes, zero IPv6 prefixes, with no peers, upstreams, or downstreams in the global routing table as of 2026-06-18. It is therefore best described as a dormant/legacy ASN rather than a production network — the university's active campus routing is carried under other ASNs (AS36375 and siblings), with upstream transit and research connectivity historically channelled through Merit Network (AS237), the Michigan regional research-and-education network the university co-founded in 1966. No notable public abuse signal was found against AS178 as a source ASN as of June 2026; the address space's abuse-report footprint is driven by disclosed, ethically-conducted ZMap research scanning (the same U-M lineage that produced Censys) and a Tor exit node on one host, not malicious operator behavior. The university was a data-breach *victim* in August 2023, which is victim context, not threat-actor context.

Operator

Regents of the University of Michigan (commonly University of Michigan); ARIN registrant org IT Communications Services, 4251 Plymouth Road Suite 2-2200, Ann Arbor, MI 48105-3640 [Confirmed] — ARIN RDAP (https://rdap.arin.net/registry/autnum/178)

Country / RIR

US (Ann Arbor, Michigan), ARIN [Confirmed] — ARIN RDAP

Allocated

ARIN ASN registration 1988-04-28; ASN record last changed 2020-01-14 (this is the ARIN registry date, not an IEEE attribution — IEEE publishes no such dates) [Confirmed for the shown dates] — ARIN RDAP

Org status

active holder (public research university; state institution of Michigan, founded 1817). Operator contacts — admin Internet Numbers Administration (internet-numbers@umich.edu, +1-734-647-4200); technical UMnet Administration (umnet-admin-team@umich.edu); abuse IT Abuse Investigation (report-abuse@umich.edu, +1-734-764-4357)

[Confirmed] — ARIN RDAP / ipinfo.io

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal against AS178 as a source ASN found as of 2026-06-18; not observed on Spamhaus ASN-DROP [Likely — live asndrop.txt not directly fetched]. Report footprint driven by disclosed ZMap research scanning (Censys lineage) and a Tor exit node (35.0.127.52); U-M was a breach *victim* in Aug 2023 (~230,000 individuals), not a threat actor — abuseipdb.com / michigan.gov / securityweek.com

Network & routing

Network type

university / academic research network, legacy ASN currently dormant (no active BGP announcements vs the university's active AS36375) [Confirmed] — bgp.tools / ipinfo.io

Size

zero IPv4 prefixes, zero IPv6 prefixes — not in the global routing table; address-space estimate Unknown (no prefixes originated) — bgp.he.net / bgp.tools (2026-06-18)

Routing/peering

no upstreams, peers, or downstreams observed; no public peering policy for AS178 specifically. The university's active AS36375 has a selective/closed academic posture channelled via Merit Network AS237, with research peers Internet2 (AS11537) and ESnet (AS293) [Likely for the active-AS peers; Confirmed that AS178 itself has none] — bgp.tools/as/36375

RPKI

Unknown — bgp.he.net shows 0 valid / 0 invalid origins, consistent with no prefixes being announced; no ROAs verifiable from live data

Notable usage

a legacy early-Internet ASN (registered 1988) reflecting U-M's role in early academic networking; the university operates the UMnet campus backbone, with Internet2 and Merit/MiNet connectivity. AS178 itself carries no active traffic today — umich.edu / its.umich.edu

Related ASNs

AS36375 (active U-M campus ASN), plus sibling legacy ASNs (AS177, AS179, AS180) and AS237 (Merit Network, upstream/R&E network co-founded by U-M) [Likely for the sibling set; Confirmed for AS36375 active and AS237 Merit]

Analyst note

Encountered as a dormant legacy university ASN; registry resolves to University of Michigan but no live routing. The RDAP "startAutnum: 17…" seen in raw fetch is a 12,000-byte stdout truncation artifact, not real ARIN block data — the record is a single-ASN record for AS178.