Autonomous system
AS3378 MCI-ASN
Unclassified ARIN
IPv4 addresses
64.00K
30 prefixes
IPv6 prefixes
0
counted as prefixes, not addresses
Countries
1
mostly US
Flagged prefixes
0
none
Summary
Verizon Business (MCI)
transit isp legacy
The last of the four consecutive legacy MCI autonomous systems (MCI-ASN)
held by Verizon Business, and the busiest of the group by prefix count.
What it's used for
- Announcing a broad scatter of MCI-era IPv4 blocks for Verizon Business, predominantly customer and managed-service address space.
- Backbone transit proper is carried by [AS701](https://asn.ipinfo.app/AS701); this ASN exists mainly to originate legacy prefixes.
Notable
- Registered to Verizon Business in Ashburn, Virginia, with an ARIN record reaching back to the mid-1990s.
- The prefixes are numerous but mostly small (many /22s and /24s) — the signature of address space handed out to individual customer sites over decades.
Interesting
- Together with [AS3375](https://asn.ipinfo.app/AS3375), [AS3376](https://asn.ipinfo.app/AS3376) and [AS3377](https://asn.ipinfo.app/AS3377), it forms a contiguous four-ASN run that MCI claimed early and Verizon never retired.
This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy. Source, and how to suggest an edit.
Address space
Summary
| Country | Name | Prefixes |
|---|---|---|
| US | United States of America | 30 |
Registry
Allocation record
- Registry
- ARIN
- Handle
AS3369- Registry name
- MCI-ASN
- Registrant
- Verizon Business
- Abuse contact
- abuse@verizon.com
- Registered
- 1994-01-06
- Last changed
- 2024-07-02
- Status
- active
Reputation
Classification and threat
Unclassified Not in the curated lists. Most of the ~80,000 allocated ASNs are not.
No IC3 indicators Nothing from the FBI IC3 feed.
Threat data is alpha. Absence of an indicator is not evidence of good behaviour, only of absence from this one feed.
Elsewhere