AS519

AS519 is a legacy autonomous system number registered under ARIN to "Systemhouse/INTERACTIVE Systems" (ARIN AS-name ISCNET), based in Naperville, Illinois. The registry record traces to a chain of 1980s–1990s corporate mergers: Interactive Systems Corporation (ISC), an early commercial Unix vendor, was acquired by Eastman Kodak in 1988, and the non-Unix remainder of that business was absorbed by SHL Systemhouse Inc. in 1993 — a transition that lines up closely with the ASN's own ARIN "last changed" timestamp of 1993-04-13. SHL Systemhouse was itself acquired by MCI Communications in 1995 and folded into EDS in 1999, meaning no independent corporate entity has operated under this name for over two decades. Consistent with that history, AS519 shows no live footprint today: zero announced IPv4/IPv6 prefixes, zero observed BGP peers or upstreams, and a CAIDA customer cone limited to itself. RIPEstat records a single brief historical sighting of the prefix 187.62.224.0/19 for one day in May 2010, which reads as a routing anomaly rather than sustained address use. The ASN's technical point of contact has been flagged unvalidated by ARIN since 2014, and no public abuse, hijack, or NANOG community record exists for it — a clean but dormant registration.

Operator

Systemhouse/INTERACTIVE Systems (ARIN AS-name ISCNET; registrant handle SYSTEM-176), Naperville, IL, US [Confirmed] — https://rdap.arin.net/registry/autnum/519

Country / RIR

US, ARIN [Confirmed] — RIPEstat abuse-contact-finder (authoritative_rir: arin)

Allocated

1989-09-14 (ARIN RDAP autnum TOP-LEVEL "registration" event); last changed 1993-04-13 (autnum top-level "last changed" event) [Confirmed] — https://rdap.arin.net/registry/autnum/519

Org status

registry status "active" (not revoked), but the sole ARIN POC (Michael Borowiec, MB487-ARIN, tellabs.com email) has been flagged unvalidated by ARIN since 2014-10-24, and the underlying corporate entity (Systemhouse/INTERACTIVE Systems) has not existed independently since its 1999 absorption into EDS — legacy/likely-dormant registration

[Confirmed] — https://rdap.arin.net/registry/autnum/519

Contacts

the sole abuse/technical POC is a named individual, Michael Borowiec (MB487-ARIN), unvalidated since 2014-10-24; his personal mailbox — on a tellabs.com domain unrelated to the registrant — is not reproduced here. Registrant address P.O. Box 6572 / 1901 North Naper Blvd., Naperville, IL 60567

[Confirmed] — https://rdap.arin.net/registry/autnum/519

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-10 — AS519 is not present in the Spamhaus ASN-DROP list; no NANOG-archive or hijack-history hits found [Confirmed for DROP-list absence; Unknown for hijack history] — https://www.spamhaus.org/drop/asndrop.json

Network & routing

Network type

Unknown — no operator-official site exists to classify AS519 (ISP/enterprise/hosting); registry-only record [Likely] — https://rdap.arin.net/registry/autnum/519, https://www.peeringdb.com/asn/519 (404, no PeeringDB network record)

Size / routing

dormant — 0 IPv4 and 0 IPv6 prefixes currently announced; customer cone = 1 ASN (itself), 0 prefixes, 0 addresses; CAIDA AS rank 79,459 [Confirmed] — https://stat.ripe.net/AS519, https://asrank.caida.org/asns/519, https://bgp.he.net/AS519

Routing/peering

NOT announced — 0 RIS peers seeing it (0/327 v4, 0/321 v6); CAIDA degree total 0 (customer 0, peer 0, provider 0); no peers or upstreams visible in any source [Confirmed] — https://stat.ripe.net/AS519, https://asrank.caida.org/asns/519

Routing history

single one-day BGP sighting of 187.62.224.0/19 (first_seen 2010-05-08, last_seen 2010-05-09) — a historical anomaly, not sustained address use [Confirmed] — https://stat.ripe.net/AS519

RPKI

not assessable — no prefixes currently announced, so there are no ROAs to validate; bgp.he.net shows no valid/invalid originated routes [Confirmed] — https://bgp.he.net/AS519

Notable usage

Unknown from operator-official sources; third-party aggregators list it only as "ISCNET / Systemhouse/INTERACTIVE Systems" with no domains, peers, or current usage documented [Unknown] — no operator-official citation available (PeeringDB has no record; no corporate site)

Corporate lineage

name traces to Interactive Systems Corporation (Unix vendor, acquired by Eastman Kodak 1988) and SHL Systemhouse Inc. (acquired ISC's non-Unix remainder 1993, matching the RDAP last-changed date); SHL Systemhouse acquired by MCI Communications 1995, folded into EDS 1999 — no independent entity operates under this name today

[Likely] — https://en.wikipedia.org/wiki/Interactive_Systems_Corporation, https://en.wikipedia.org/wiki/MCI_Systemhouse

Analyst note

legacy 1989 ASN whose registrant name reflects a defunct 1990s Unix/systems-integration lineage (ISC → SHL Systemhouse → MCI Systemhouse → EDS); registry-active but zero current routing footprint across every source checked.