AS236

AS236 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. Like AS181, it sits in Merit's historical block and is dormant today: every routing source consulted (bgp.he.net, bgp.tools) agrees it announces zero IPv4 and zero IPv6 prefixes and has not been visible in the global routing table since 2011-02-01 — dark for over fourteen years as of June 2026. Merit's active operational routing runs under AS237. The ARIN RDAP autnum record (handle AS236, name MERIT-AS-13, org handle MICH-Z) carries a top-level registration event of 1988-09-12, placing AS236 among the earliest allocated ASNs, well before the modern BGP era; the record was last changed 2012-04-02. When active, the ASN originated two IPv4 prefixes (192.35.164.0/22 and 192.35.169.0/24, roughly 1,280 addresses) and one IPv6 prefix (2620:0:ce0::/48), with historical upstreams AT&T (AS7018) for IPv4 and Hurricane Electric (AS6939) for IPv6. RPKI posture is not assessable: with no active originations there are no ROAs to validate, and bgp.he.net reports zero RPKI-valid and zero RPKI-invalid origins (its "bogon" annotation refers to legacy 192.35.x originations that are legitimately IANA-assigned space but may trip older bogon filters). Merit's organizational pedigree is significant — it operated the NSFNET backbone (1987–1995), the direct precursor of the commercial Internet, and still operates RADb, a major Internet Routing Registry. No notable public abuse signal was found as of June 2026 — not in Spamhaus ASN-DROP, CleanTalk, AbuseIPDB, or NANOG archives — consistent with a clean, dormant ASN held by a respected R&E operator.

Operator

Merit Network, Inc. (nonprofit R&E network; ARIN org handle MICH-Z, Ann Arbor, MI) [Confirmed] — ARIN RDAP autnum/236, merit.edu/about

Country / RIR

US, ARIN [Confirmed] — ARIN RDAP autnum/236

Allocated

1988-09-12 (ARIN registry date from 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), governed by Michigan's public universities; founded 1966; HQ 880 Technology Drive, Suite B, Ann Arbor, MI 48108 [Confirmed] — merit.edu/about, en.wikipedia.org/wiki/Merit_Network

Contacts

abuse@merit.edu / +1-734-527-5740; operations@merit.edu; ipreg@merit.edu; HQ 880 Technology Drive, Suite B, Ann Arbor, MI 48108 [Confirmed via ARIN RDAP autnum/236]

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-20 — not in Spamhaus ASN-DROP, CleanTalk, AbuseIPDB, or NANOG archives; dormant ASN under a respected R&E operator, with no active routing to generate abuse traffic — spamhaus.org/drop/asndrop.txt, cleantalk.org/blacklists/asn

Network & routing

Network type

regional research and education (R&E) network; AS236 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 currently announced; historically 2 IPv4 prefixes (192.35.164.0/22, 192.35.169.0/24 ≈ 1,280 addresses) and 1 IPv6 prefix (2620:0:ce0::/48) [Confirmed] — bgp.he.net/AS236, bgp.tools/as/236

Routing/peering

NOT announced — not visible in the global routing table since 2011-02-01; 0 currently announced prefixes per bgp.he.net and bgp.tools. Historical upstreams: AS7018 (AT&T) via IPv4, AS6939 (Hurricane Electric) via IPv6 [Confirmed]. Merit's active AS237 runs a Selective peering policy (peering@merit.edu) [Likely for AS237 policy]

RPKI

not assessable — AS236 announces no prefixes, so there are no ROAs to validate; bgp.he.net shows 0 RPKI-valid and 0 RPKI-invalid origins [Confirmed]. (bgp.he.net "bogon" note refers to legacy 192.35.x originations, legitimately IANA-assigned, that may trip older bogon filters) [Likely]

Notable usage

Merit operated the NSFNET backbone (1987–1995), interconnected with ARPANET in 1983, and operates RADb (IRR). AS236 (MERIT-AS-13) is a legacy Merit ASN; active infrastructure now runs under AS237 — merit.edu/research/projects/the-nsfnet-backbone-service, en.wikipedia.org/wiki/Merit_Network, bgp.he.net/AS236

Related ASNs

AS237 (Merit's active operational network); AS181 (MERIT-AS-1, another dormant legacy Merit ASN) [Confirmed for AS237; Confirmed for AS181 as sibling Merit ASN]

Analyst note

Encountered as a dormant legacy ASN registered to a historically significant R&E operator; WHOIS resolves to Merit Network, but live routing is under AS237, not AS236. Clean, inactive ASN. The entity-level registration dates in the RDAP entities[] block (e.g. 2002-09-20, 1999-02-18, 2009-12-08) are POC/org decoys; allocated_date is taken solely from the autnum top-level registration event.