AS204

AS204 is a legacy autonomous system number registered under ARIN to the Pittsburgh Supercomputing Center (PSC), a federally funded research-and-education (R&E) institution founded in 1986 as one of the original five NSF supercomputing centers and jointly operated by Carnegie Mellon University and the University of Pittsburgh. The ASN dates to 1988-06-15 per the ARIN RDAP autnum top-level registration event, placing it among the earliest assigned numbers. The key triage point for AS204 is that it is effectively dormant today: every routing source consulted (RIPEstat, CAIDA AS Rank, bgp.he.net, IPinfo) agrees it announces zero IPv4 and zero IPv6 prefixes, has zero visible BGP peers, zero upstreams, zero customers, and no IXP memberships. Its CAIDA AS rank of 79,459 sits near the bottom of the global ranking and its customer cone is a singleton (the ASN itself, 0 prefixes, 0 addresses), so RPKI posture cannot be assessed because there are no active originations and therefore no ROAs. PSC's active connectivity now runs under other ASNs it holds (notably AS1207, AS5050); the Advanced Networking Group operates the Three Rivers Optical Exchange (3ROX), a regional GigaPoP serving research and education sites across western and central Pennsylvania and West Virginia, and develops HPN-SSH. No notable public abuse signal was found as of June 2026 — not in Spamhaus ASN-DROP, CleanTalk, NANOG archives, or the Spamhaus suspicious-network-resurrection report — consistent with a clean, dormant ASN held by a respected R&E operator.

Operator

Pittsburgh Supercomputing Center (PSC) (federally funded nonprofit R&E center; ARIN registrant handle PSC-Z, Pittsburgh, PA) [Confirmed] — ARIN RDAP, psc.edu/about

Country / RIR

US, ARIN [Confirmed] — ARIN RDAP autnum; RIPEstat abuse-contact-finder

Allocated

1988-06-15 (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 federally funded nonprofit research center; founded 1986; supported by NSF, other federal agencies, the Commonwealth of Pennsylvania, and private industry; jointly operated by Carnegie Mellon University and the University of Pittsburgh [Confirmed] — psc.edu/about

Contacts

pscnet-admin@psc.edu; +1-412-268-4960; 300 S Craig St, Pittsburgh, PA 15213. Admin: Michael H Lambert. Technical/abuse: Stephen Cunningham — both individual mailboxes (psc.edu) are in the ARIN RDAP record [Confirmed] — ARIN RDAP, RIPEstat abuse-contact-finder

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-19 — not in Spamhaus ASN-DROP (430-entry feed, no asn=204), CleanTalk (empty metrics), NANOG archives, or the Spamhaus suspicious-network-resurrection report; PSC was a TeraGrid partner during the April 2004 supercomputer-center intrusions but was not itself reported compromised; dormant ASN under a respected R&E operator

Network & routing

Network type

research and education (R&E) network; AS204 is legacy/inactive (PSC's active connectivity runs under other ASNs, e.g. AS1207/AS5050) [Confirmed] — psc.edu/research/networking, bgp.he.net/AS204

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 (2026-06)

Routing/peering

NOT announced — 0 RIS peers seeing it (0/327 v4, 0/323 v6); CAIDA degree total 0 (customer 0, peer 0, provider 0); no upstreams or peers visible in any source [Confirmed]. No public peering policy page found; PeeringDB /asn/204 returned 404 [Unknown for AS204 policy]

RPKI

not assessable — AS204 announces no prefixes, so there are no ROAs to validate [Confirmed] — RIPEstat rpki-validation (skipped, no prefix)

Notable usage

PSC is one of the original five NSF Supercomputing Centers (est. 1986); provides HPC access (Bridges-2), large-scale storage, and high-performance networking; its Advanced Networking Group runs 3ROX (Three Rivers Optical Exchange), a regional GigaPoP for PA and WV, and develops HPN-SSH (High Performance Enabled SSH). AS204 (PSCNET-AS) is an early/legacy PSC ASN — psc.edu/about, en.wikipedia.org/wiki/Pittsburgh_Supercomputing_Center

Related ASNs

PSC also holds AS1207 and AS5050 (active connectivity) [Likely per third-party DB] — bgp.tools/as/1207, ipinfo.io/AS204

Analyst note

Encountered as a dormant legacy ASN registered to a historically significant R&E operator; WHOIS resolves to PSC, but live routing runs under other PSC ASNs, not AS204. The entity-level RDAP event dates (1999-05-19, etc.) are org/contact artifacts; the authoritative registration is the autnum top-level 1988-06-15. Clean, inactive ASN.