asn.dev

Autonomous system

AS18438 BROWNB

Unclassified ARIN

IPv4 addresses 5.12K 9 prefixes
IPv6 prefixes 0 counted as prefixes, not addresses
Countries 1 mostly US
Exchanges 0 recorded by PCH
Upstreams 9 0 downstream
Flagged prefixes 0 none

Summary

Brown Brothers Harriman & Company

United States of America · AI-generated

business finance corporate

BROWNB is the autonomous system for Brown Brothers Harriman & Company.

What it's used for

  • The address space carries corporate infrastructure, evidenced by netnames BBHNET, BBHNET1, and BBHNET8 registered to Brown Brothers Harriman & Company.
  • The AS announces 5120 IPv4 addresses across 9 prefixes with 9 observed neighbours, indicating a small, self-contained corporate network rather than a transit or access provider.

Notable

  • Registrants align with the announcer for most prefixes, listing Brown Brothers Harriman & Company or Brown Brothers Harriman & Co., though two prefixes (192.200.4.0/22 and 192.200.2.0/23) are registered to "Various Registries (Maintained by ARIN)" with netname NET192.
  • The inventory consists of a mix of /21, /22, /23, and /24 blocks, primarily in the 204.136.0.0/16 and 192.200.0.0/16 ranges, with no IPv6 prefixes announced.

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

9 upstream, 0 downstream and 9 adjacent networks observed; most-used upstreams first.

ASNetworkPaths seen
AS55002F5, Inc.638
AS174Cogent Communications, LLC116
AS46887Crown Castle Fiber LLC110
AS3356Level 3 Parent, LLC98
AS54004Cablevision Lightpath LLC73
AS2516KDDI CORPORATION59
AS6461Zayo Bandwidth31
AS8220COLT Technology Services Group Limited28

All 9 upstreams →

Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-19, 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 9 prefixes · 5.12K addresses IPv6 0 prefixes

CountryNamePrefixes
USUnited States of America9

Registry

Allocation record

ARIN · via Atlas (registry + RDAP)
Registry
ARIN
Handle
AS18438
Registry name
BROWNB
Registrant
Brown Brothers Harriman & Company
Abuse contact
hostmaster@bbh.com
Registered
2000-08-29
Last changed
2017-04-22
Allocation
assigned

Routing security

RPKI and IRR

Full detail
RPKI
15% valid · 3 valid, 17 with no ROA
ROAs
3 authorising AS18438
ASPA
no ASPA record
IRR
90% registered · 18 of 20 announcements
Route objects
36 naming AS18438

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 1,778 prefixes, as published 2026-10-20. 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