asn.dev

Autonomous system

AS23427 GLENBARD-HSD87

Unclassified ARIN

IPv4 addresses 1.02K 1 prefixes
IPv6 prefixes 0 counted as prefixes, not addresses
Countries 1 mostly US
Exchanges 0 recorded by PCH
Upstreams 1 0 downstream
Flagged prefixes 0 none

Summary

Glenbard HSD #87

United States of America · AI-generated

education k12 network usa

GLENBARD-HSD87 is the autonomous system for Glenbard HSD #87, a public school district in Illinois.

What it's used for

  • The space carries the district's internal network infrastructure, identified by the netname GLENB-3 and registrant Glenbard HSD #87.
  • The AS announces a single IPv4 prefix, 204.145.108.0/22, comprising 1024 addresses, with 0 IPv6 prefixes.
  • With only 1 observed neighbour, the low address-to-neighbour ratio indicates a stub or access network rather than a transit provider.

Notable

  • The RDAP registrant Glenbard HSD #87 matches the AS holder name exactly, confirming direct ownership of the address space.
  • The address inventory consists of a single contiguous /22 block, typical for a small-scale organizational network.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy. Source, and how to suggest an edit.

Interconnection

Peering at a glance

Full topology · Graph

Internet exchanges

No exchange port on file. Many exchanges publish no participant list, so this is not proof of absence.

Transit providers

1 upstream, 0 downstream and 1 adjacent networks observed; most-used upstreams first.

ASNetworkPaths seen
AS6325Illinois Century Network57

Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-16, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.

Address space

Summary

Shape and geography

IPv4 1 prefixes · 1.02K addresses IPv6 0 prefixes

CountryNamePrefixes
USUnited States of America1

Registry

Allocation record

ARIN · via Atlas (registry + RDAP)
Registry
ARIN
Handle
AS23427
Registry name
GLENBARD-HSD87
Registrant
Glenbard HSD #87
Abuse contact
Nate_Dhamers@glenbard.org
Registered
2009-11-12
Last changed
2012-02-24
Allocation
assigned

Routing security

RPKI and IRR

Full detail
RPKI
0% valid · 0 valid, 1 with no ROA
ROAs
0 authorising AS23427
ASPA
no ASPA record
IRR
100% registered · 1 of 1 announcements
Route objects
2 naming AS23427

Reputation

Classification and threat

Unclassified Not in the curated lists. Most of the ~80,000 allocated ASNs are not.

Spamhaus DROP

Not on ASN-DROP The network as a whole is not listed.

No DROP prefixes None of its announced space is on the DROP prefix list.

Spamhaus DROP ("Don't Route Or Peer") lists space and networks run by, or hijacked for, spam and cybercrime operations: 442 networks and 1,783 prefixes, as published 2026-10-17. A short, high-confidence list, so a match is worth taking seriously, and absence from it says little on its own.

FBI IC3

No IC3 indicators Nothing from the FBI IC3 feed.

IC3 threat data is alpha. Absence of an indicator is not evidence of good behaviour, only of absence from this one feed.

Elsewhere

Cross-check