AS238

AS238 is a legacy autonomous system number registered under ARIN to Merit Network, Inc., the nonprofit research-and-education (R&E) network founded in 1966 and governed by Michigan's public universities. The ASN carries notable historical weight: Merit operated the NSFNET backbone — the direct predecessor of the modern commercial Internet — from 1987 to 1995 under a National Science Foundation award, and it founded and still operates RADb, one of the largest public Internet Routing Registries used worldwide for BGP route registration. The key triage point for AS238 is that it is effectively dormant today. Every routing source consulted (RIPEstat, CAIDA AS Rank, bgp.he.net, bgp.tools) agrees it announces zero IPv4 and zero IPv6 prefixes, has zero visible BGP peers, zero upstreams, zero customers, and no IXP memberships. RIPEstat's routing history shows the last prefix (192.65.215.0/24) was seen on 2001-10-19, with no routing activity recorded since — so the ASN has been out of the global table for over two decades. Its CAIDA AS rank of 79,459 sits near the bottom of the global ranking, reflecting complete routing inactivity, and its customer cone is a singleton (the ASN itself, 0 prefixes, 0 addresses). Merit's active operational routing runs under AS237, which carries the live network over roughly 4,000 miles of owned Michigan fiber and runs a Selective peering policy. RPKI posture cannot be assessed for AS238 because there are no active originations and therefore no ROAs. No notable public abuse signal was found as of June 2026 — not in Spamhaus ASN-DROP, CleanTalk, NANOG archives, or RADb route objects — consistent with a clean, dormant ASN held by a respected R&E operator.

Operator

Merit Network, Inc. (nonprofit R&E network; ARIN registrant handle MICH-Z, Ann Arbor, MI) [Confirmed] — ARIN RDAP, merit.edu/about

Country / RIR

US, ARIN [Confirmed] — ARIN RDAP autnum

Allocated

1988-09-12 (ARIN registry date — the autnum top-level registration event, NOT an IEEE date; IEEE publishes no ASN registration dates); last changed 2012-04-02 [Confirmed] — ARIN RDAP autnum top-level events

Org status

active independent nonprofit corporation (Merit Network), member-governed by Michigan's public universities (founding members Michigan State University, University of Michigan, Wayne State University); founded 1966; operated the NSFNET backbone under an NSF award

[Confirmed] — merit.edu/about, en.wikipedia.org/wiki/Merit_Network

Contacts

abuse@merit.edu (+1-734-527-5740); operations@merit.edu (+1-734-527-5717, technical); ipreg@merit.edu (administrative); HQ 880 Technology Drive, Suite B, Ann Arbor, MI 48108 [Confirmed] — ARIN RDAP

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-20 — not in Spamhaus ASN-DROP (absent across all entries), NANOG/MARC archives (zero hits), or RADb (no route objects registered); dormant ASN under a respected R&E operator. ThreatFox and AbuseIPDB per-ASN lookups were not retrievable (bot-challenge / HTTP 404) and remain Unknown rather than confirmed-clean

Network & routing

Network type

regional research and education (R&E) network; AS238 is legacy/inactive (Merit's active network runs under AS237) [Confirmed] — merit.edu/about, peeringdb.com/net/928

Size

dormant — 0 IPv4 prefixes / 0 IPv4 addresses and 0 IPv6 prefixes; customer cone = 1 ASN (itself), 0 prefixes, 0 addresses [Confirmed] — RIPEstat routing-status / CAIDA AS Rank / bgp.he.net / bgp.tools (2026-06)

Routing/peering

NOT announced — 0 RIS peers seeing it (0/327 v4, 0/324 v6); CAIDA degree total 0 (customer 0, peer 0, provider 0); no upstreams or peers visible in any source [Confirmed]. Last prefix seen 2001-10-19 (192.65.215.0/24); no activity since [Confirmed] — RIPEstat routing-status. Merit's active AS237 runs a Selective peering policy

[Likely for AS237 policy] — peeringdb.com/net/928

RPKI

not assessable — AS238 announces no prefixes, so there are no ROAs to validate [Confirmed] — RIPEstat rpki-validation (no prefix to validate)

Notable usage

Merit operated the NSFNET backbone (1987–1995) and operates RADb (IRR); Merit was founded in 1966 and connected to ARPANET in 1983. AS238 (MERIT-AS-15) is an early/legacy Merit ASN; active infrastructure now runs under AS237 — merit.edu/about, radb.net, en.wikipedia.org/wiki/Merit_Network

Related ASNs

AS237 (Merit's active operational network); Merit holds additional legacy ASNs (e.g. AS181–185, AS229–238, AS689) [Confirmed for AS237; Likely for the broader block list per third-party DB]

Analyst note

Encountered as a dormant legacy ASN registered to a historically significant R&E operator; WHOIS/RDAP resolves to Merit Network, but live routing is under AS237, not AS238. Clean, inactive ASN. A5 (community angle) abstained on the allocation date; the 1988-09-12 date is confirmed first-party from the ARIN RDAP autnum top-level registration event (corroborated by A2, A3, A4).