Autonomous system
AS4473 ATTIS-ASN4473
Unclassified ARIN
Summary
AT&T Internet Services
enterprise legacy
ATTIS-ASN4473 — an AT&T Internet Services autonomous system, registered with ARIN in 1995 and held today by AT&T Enterprises, LLC.
What it's used for
- Announcing several dozen AT&T prefixes, largely carved out of AT&T's legacy
12.0.0.0/8, for enterprise and managed customer networks. - One of many ASNs AT&T maintains alongside its main backbone (AS7018) for specific service segments.
Notable
- Business address space, not consumer broadband: the /24s here look like customer and service assignments rather than subscriber pools.
- The wide spread of small prefixes is typical of an ASN used to originate enterprise customer routes out of a carrier's own aggregate.
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
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 4 adjacent networks observed; most-used upstreams first.
| AS | Network | Paths seen |
|---|---|---|
| AS7018 | AT&T Enterprises, LLC | 1,885 |
Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-10, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.
Address space
Summary
IPv4 21 prefixes · 78.34K addresses IPv6 0 prefixes
| Country | Name | Prefixes |
|---|---|---|
| US | United States of America | 21 |
Registry
Allocation record
- Registry
- ARIN
- Handle
AS4473- Registry name
- ATTIS-ASN4473
- Registrant
- AT&T Enterprises, LLC
- Abuse contact
- abuse@att.net
- Registered
- 1995-03-08
- Last changed
- 2024-12-05
- Allocation
- assigned
Routing security
RPKI and IRR
- RPKI
- 0% valid · 0 valid, 32 with no ROA
- ROAs
- 5 authorising AS4473
- ASPA
- no ASPA record
- IRR
- 0% registered · 0 of 32 announcements
- Route objects
- 4 naming AS4473
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: 431 networks and 1,775 prefixes, as published 2026-10-11. 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