AS177

AS177 is one of the earliest Autonomous System Numbers ever issued, registered with ARIN under the name UMICH-AS-1 to the Regents of the University of Michigan in Ann Arbor. The ARIN RDAP record shows the ASN registered on 1988-04-28, placing it among the legacy allocations that pre-date the modern commercial Internet; this is an ARIN registry artifact, not an IEEE or IANA publication date. The registrant org handle is UNIVER-118-Z and the network is administered by the university's IT Communications Services / UMnet Administration team. Operationally, AS177 today is a small stub network: across bgp.he.net and bgp.tools it originates no IPv4 prefixes and exactly two IPv6 /48 prefixes (2001:48a8:68fd::/48 and 2607:f018:fffe::/48), reaching the wider Internet through a single upstream, AS237 (Merit Network Inc.) — Michigan's regional research-and-education network, which connects U-M to Internet2. Both announced prefixes are RPKI ROA-valid with zero invalids, and the customer cone contains only AS177 itself, confirming there are no downstream transit customers. No notable public abuse signal was found across blocklists, NANOG archives, or threat feeds as of 2026-06-18; the operator is in fact a defensive threat-intelligence contributor (MITN) and the academic home of the Censys/ZMap internet-measurement projects, so any scanning traffic from U-M space should be read in a research context rather than as adversarial.

Operator

Regents of the University of Michigan (commonly University of Michigan, Ann Arbor; registrant org handle UNIVER-118-Z) [Confirmed] — ARIN RDAP

Country / RIR

US (Ann Arbor, MI 48105-3640), ARIN [Confirmed] — https://rdap.arin.net/registry/autnum/177

Allocated

ARIN ASN RegDate 1988-04-28 (an ARIN registry artifact among the earliest legacy allocations, NOT an IEEE/IANA publication date); autnum last changed 2020-01-14 [Confirmed] — https://rdap.arin.net/registry/autnum/177

Org status

active — public university governed by the constitutionally independent Regents of the University of Michigan; flagship of the U-M system [Confirmed] — https://en.wikipedia.org/wiki/University_of_Michigan

Contacts

Admin — internet-numbers@umich.edu, +1-734-647-4200; Technical (UMnet Admin) — umnet-admin-team@umich.edu, +1-734-647-4200; Abuse — report-abuse@umich.edu, +1-734-764-4357 [Confirmed] — ARIN RDAP

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-18 across AbuseIPDB, Spamhaus, bad-ASN blocklists, and NANOG archives; operator runs MITN threat-sharing and is the academic origin of Censys/ZMap

Network & routing

Network type

education / research stub (end-site) network; non-transit, IPv6-only origination as of fetch date [Confirmed] — https://bgp.he.net/AS177, https://bgp.tools/as/177

Size

small — 0 IPv4 prefixes originated, 2 IPv6 /48 prefixes; customer cone = 1 (itself); ~4.532 average AS path length over 666 IPv6 paths — bgp.he.net / bgp.tools (2026-06)

Routing/peering

single upstream AS237 (Merit Network Inc.); 1 BGP peer observed (IPv6); no public peering policy found on PeeringDB or operator site [Confirmed for upstream/peers; peering policy Unknown] — https://bgp.he.net/AS177, https://bgp.tools/as/177

RPKI/routing security

strong — both IPv6 prefixes ROA-valid, 0 invalid; IRR records maintained in RADB as UMICH-AS-1 [Confirmed] — https://bgp.he.net/AS177

Notable usage

one of the earliest ASNs assigned; operated by a major US R1 public research university (founded 1817). U-M is a founding Merit member and participates in Internet2 via Merit; the Michigan Innovation Network (MiNet) fiber ring links U-M with Michigan State and Wayne State via Merit — en.wikipedia.org/wiki/University_of_Michigan, its.umich.edu, merit.edu

Related ASNs

AS237 (MERIT, Merit Network — sole upstream); AS36375 (University of Michigan's primary modern ASN, distinct from this legacy AS177) [Confirmed for AS237; AS36375 Likely] — bgp.he.net, bgpview.io/asn/177

Analyst note

a small, well-secured, IPv6-only legacy stub under a major research university; clean reputation by negative evidence. AS177 is distinct from the university's modern AS36375.