Check-Host.cc

IP Address IPv4

203.138.19.127

Aggregated from public BGP, CT logs, our scan layer, honeypots and global probes.

Run a live full scan of 203.138.19.127

On-demand: ports, banners, TLS, tech-stack, subdomains and origin/IP-leak detection. Results are shared publicly for everyone to link to.

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ASN
AS2514
NTT PC Communications (InfoSphere)
Country
AU
Australia
Reverse DNS
ykw.elec.keio.ac.jp
PTR
Open Ports
4
Last scan

Autonomous System

ASN
AS Name
NTT PC Communications (InfoSphere)
AS Type
RIR
APNIC
Allocated
1996-05-21
Allocation status
Allocated

Geolocation

Country
AU · Australia
Continent
Oceania
Source
MaxMind GeoLite2

Reverse DNS

Last seen
2026-06-16 11:26:08

Network

RPKI

Open Ports

Port Proto Service Server Last seen
80 tcp http Apache 2026-05-26 08:41:30.000
110 tcp pop3 2026-06-16 11:24:53.000
587 tcp smtp-submission 2026-05-26 00:15:39.000
8000 tcp http-alt Apache 2026-06-15 21:58:34.000

TLS Certificates

TLS certificate observations pending

Once our scan layer captures a TLS cert from this IP, certificate chain, JARM and JA4S fingerprints will appear here.

Tech Stack

Detected via Wappalyzer-style rules on the HTTP response body, headers, scripts and meta tags.

Origin / IP-Leak

USP

When a hostname is served behind a CDN (e.g. Cloudflare), the origin server can sometimes be identified by matching its TLS cert against the protected hostname. Findings shown here are heuristic candidates, not guarantees.

No origin-leak candidates for this IP

When this IP serves a TLS cert for a domain that fronts behind a CDN, that domain surfaces here as an origin-leak candidate with a confidence score.

Hosted Domains

1 domain resolve (A-record) to this IP.

Multi-Vantage Check

Reachability accrued passively from real user-triggered checks across our 65+ probe nodes. Run a live check to add fresh data.

No accumulated reachability data yet

Reachability accrues from real user-triggered checks. Trigger a Ping or HTTP check from our 65+ probe nodes to contribute the first data point.

Web Pages

Port Page title Status Flags
8000 401 Authorization Required 401
80 慶応義塾大学 湯川研究室 200

Threat Intelligence

No threat-intel matches

This IP doesn't appear in any of the feeds we mirror (Tor exits, FireHOL Level 1-3, Spamhaus DROP/EDROP, URLhaus, OpenPhish). Absence here doesn't prove the IP is clean — it just means none of our public-feed sources flag it.

Co-Hosted Domains

Domains this host references in its HTML AND whose DNS A/AAAA record resolves back to this IP — i.e. actually hosted here.

www.ykw.elec.keio.ac.jp DNS-confirmed

External References

Domains the body links to whose DNS does NOT resolve to this IP — usually CDN assets, embeds, or third-party services. Boilerplate (Google Fonts, jsDelivr, w3.org…) is already filtered.

ieeexplore.ieee.org href · ×25
arxiv.org href · ×14
www.jsps.go.jp href · ×13
t.co href · ×11
www.ieice.org href · ×8
www.j-techno.co.jp href · ×6
www.jst.go.jp href · ×5
www.kll.keio.ac.jp href · ×5
www.keguanjp.com href · ×4
www.sciencedirect.com href · ×3
aip.riken.jp href · ×3
www.st.keio.ac.jp href · ×3
www.icassp2014.org href · ×3
www.taf.or.jp href · ×2
2022.eusipco.org href · ×2
2022.ieeeicassp.org href · ×2
github.com href · ×2
www.mcfund.or.jp href · ×2
www.apsipa2022.org href · ×2
www.wiley.com href · ×2
top-researchers.com href · ×2
orsj.org href · ×2
nips.cc href · ×1
icassp2015.org href · ×1
twitter.com href · ×1
jp.diginfo.tv href · ×1
www.jstage.jst.go.jp href · ×1
www.tech-kawasaki.jp href · ×1
www.ieee-jp.org href · ×1
arx.appi.keio.ac.jp href · ×1
csdui.sice-ctrl.jp href · ×1
www.ism.ac.jp href · ×1
cmsworkshops.com href · ×1
www.diginfo.tv href · ×1
www.eecs.tu-berlin.de href · ×1

History

First observed
2026-05-26 00:15
Last observed
2026-06-16 11:24
Scan observations
10

The full change-log (ASN moves, cert rotations, port-state diffs) accumulates as our archives grow.