Autonomous system
AS11452 MOUNT-SINAI
Education ARIN
Summary
Mount Sinai School of Medicine
education university research legacy
MOUNT-SINAI belongs to the Mount Sinai School of Medicine in New York City — the academic medical school now known as the Icahn School of Medicine at Mount Sinai, and the research and teaching arm of the Mount Sinai health system. It announces 14 IPv4 prefixes totalling roughly 55,000 addresses, with five observed BGP neighbours.
What it's used for
This is an academic medical centre's campus network. Nearly the whole inventory is one contiguous legacy block, 146.203/16, sliced into three /18s plus a set of longer, more specific announcements (/21, /22, /24) carved out of the same space. Deaggregating your own /16 like that is the signature of a single institution engineering its own traffic — steering particular subnets toward particular upstreams, or holding a more-specific to keep a route from being hijacked. It is not the shape of a network stitched together from acquired odds and ends.
Notable
Every prefix the pack resolved registers to MSSMEDU-1, org Mount Sinai School of Medicine. The holder announces its own registered space, which settles the question of whether the AS number and the address space have drifted apart. The five neighbours are consistent with a large institution buying redundant transit, not with a carrier: a wholesale network at this address count would show neighbours in the hundreds.
Interesting
A tens-of-thousands-of-addresses IPv4 footprint with no IPv6 announced at all is common in this cohort. The /16 was large enough that address pressure never forced the issue.
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.
Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-22, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.
Address space
Summary
IPv4 10 prefixes · 55.30K addresses IPv6 0 prefixes
| Country | Name | Prefixes |
|---|---|---|
| US | United States of America | 10 |
Registry
Allocation record
- Registry
- ARIN
- Handle
AS11452- Registry name
- MOUNT-SINAI
- Registrant
- Mount Sinai School of Medicine
- Abuse contact
- andrew.pizzimenti@mssm.edu
- Registered
- 1998-08-27
- Last changed
- 2012-03-02
- Allocation
- assigned
Routing security
RPKI and IRR
- RPKI
- 64% valid · 9 valid, 5 with no ROA
- ROAs
- 4 authorising AS11452
- ASPA
- no ASPA record
- IRR
- 64% registered · 9 of 14 announcements 3 other origin
- Route objects
- 10 naming AS11452
Reputation
Classification and threat
Education University, school or national research and education network.
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 1,779 prefixes, as published 2026-10-23. 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