AS21821

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Summary

IP address summary information
Name	Montefiore Medical Center
Country	United States
Website	host.io/montefiore.org·montefiore.org
Hosted domains	39
IPv4 addresses	1,024
IPv6 addresses	0
ASN type	Education
Registry	ARIN
Allocated	9 years ago on Apr 3, 2017
Updated	9 years ago on Apr 3, 2017

Ranking

#26,742

Overall rank

among 74,946 networks

Traffic

#20,949

Infrastructure

#13,078

#4,233inUnited States

Learn how ASN rankings work

Geolocation

Share of IPv4 footprint per hexagonLessMore

Countries by IPv4 share

United States
100%

Held location over 90 days: 100%
Held location over 1 year: 97%
Median days between moves: 432 days
Geolocation scope: City

How consistently this network's IPs hold their geolocation. Read relative to the network type, not as a quality score.

Activity

A pronounced day/night rhythm — the signature of a consumer/eyeball network whose users sleep at night.

Mon

IP Ranges

Netblock	Company	Num of IPs
144.121.102.0/24	Montefiore Medical Center	256
144.121.104.0/24	Montefiore Medical Center	256
216.255.100.0/24	Montefiore Medical Center	256
216.255.101.0/24	Montefiore Medical Center	256

IP Ranges

WHOIS


  ASHandle:       █████
  OrgID:          █████
  ASName:         ██████
  ASNumber:       AS█████
  RegDate:        ████-██-██
  Updated:        ████-██-██
  TechHandle:     ████-████
  Source:         ████

Hosted Domains

There are 39 domain names hosted across 7 IP addresses on this ASN.

IP Address	Domain	Count
216.255.101.81		32
144.121.102.111		29
216.255.101.237		2
216.255.101.123		2
216.255.101.82		1

Places

Peers

There are 2 peers for this ASN.

ASN	Name	Rank
AS32787	Akamai Technologies, Inc.
AS54004	Cablevision Lightpath LLC

Upstreams

There are 2 upstreams for this ASN.

ASN	Name	Rank
AS32787	Akamai Technologies, Inc.
AS54004	Cablevision Lightpath LLC

Downstreams

There are 0 downstreams for this ASN.

No downstreams found.

Pingable IPs

3 IPs in this ASN replied to an ICMP ping during our most recent internet scan. Learn more

IP Address	ASN	Details
144.121.102.159 Ping	AS21821Montefiore Medical Center	2.10ms from Carlstadt, US
216.255.101.212 Ping	AS21821Montefiore Medical Center	2.69ms from Carlstadt, US
216.255.100.11 Ping	AS21821Montefiore Medical Center	2.37ms from New York City, US

Other Pingable IPs

IP Address	ASN	Details
71.117.163.45 Ping	AS701Verizon Business	2.13ms from Boston, US
190.104.214.253 Ping	AS11014CPS	0.27ms from Buenos Aires, AR
154.237.72.93 Ping	AS36992ETISALAT MISR	7.88ms from Cairo, EG
110.5.235.221 Ping	AS17864SK Broadband Co Ltd	2.01ms from Incheon, KR
37.159.252.93 Ping	AS30722Fastweb SpA	4.96ms from Milan, IT
85.173.198.45 Ping	AS12389PJSC Rostelecom	18.81ms from Moscow, RU
211.141.111.253 Ping	AS56045China Mobile communications corporation	5.21ms from Nanchang, CN
61.130.242.13 Ping	AS4134CHINANET BACKBONE	2.25ms from Ningbo, CN
90.78.2.61 Ping	AS3215Orange S.A.	8.44ms from Paris, FR
190.214.23.189 Ping	AS28006CORPORACION NACIONAL DE TELECOMUNICACIONES - CNT EP	7.26ms from Quito, EC

Pingable IPs

Important routers in AS21821


216.255.100.20	New York City, United States
144.121.102.4	New York City, United States
144.121.102.2	New York City, United States
216.255.100.19	New York City, United States

Important routers in AS21821

Traceroute

Below is a recent traceroute taken from the IPinfo ProbeNet to an IP in this ASN. Learn more.Traceroute →

$ traceroute -a -n -q1 -f5 216.255.100.21

traceroute to 216.255.100.21 (216.255.100.21): 64 hops max, 52 byte packets

5 [AS32787] 23.57.110.25 1.154 ms

6 [AS21821] 216.255.100.21 2.955 ms

Measurement taken from

IPinfo ProbeNet in New York City, US

On October 16, 2026

What is an ASN?

Autonomous System Numbers (ASNs) are assigned to entities such as Internet Service Providers and other large organizations that control blocks of IP addresses. This network page, and the organization field that's shown on the main IP address information page and also returned in the geolocation API are based on the ASN.

The ASN details will often correspond to the IP address owner, but for smaller organizations it may be that organization's parent, or their ISP. Find out more about AS21821 at robtex.

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AS21821

Summary

Ranking

Geolocation

Countries by IPv4 share

Activity

IP Ranges

IP Ranges

WHOIS

Hosted Domains

Places

Peers

Upstreams

Downstreams

Pingable IPs

Other Pingable IPs

Pingable IPs

Important routers in AS21821

Important routers in AS21821

Traceroute

Related Networks

AS10356

AS23429

AS25822

AS26371

AS32996

What is an ASN?

An API built with users in mind: reliable, accurate, and easy-to-use

Our IP tools

What is my IP?

Map IPs

Summarize IPs

Pingable IPs

Other Pingable IPs

Traceroute

Ranking

IP Ranges

Important routers in AS21821

Geolocation

Countries by IPv4 share

Activity

AS10356

AS23429

AS25822

AS26371

AS32996

AS393959