# 90.181.66.137 — IP Intelligence Summary

90.181.66.137 is an IPv4 address announced by AS5610, with approximate network location Liberec, Czech Republic. It belongs to a mobile network with reverse DNS name 90-181-66-137.rco.o2.cz. As of November 12, 2026, IPDebrief rates it Low Risk (0/100); no anonymizing service was detected.

- Canonical page: https://ipdebrief.com/90.181.66.137
- Last updated: 2026-11-12

## Ownership

- Organization: AS5610-MTN
- Network name: NEXTEL-XDSL
- Allocated block: 90.181.66.0/24
- ASN: AS5610 (https://ipdebrief.com/asn/5610)
- Regional registry: RIPE
- Registered holder: AS5610-MTN
- Routing operator: —
- Network registration country: CZ
- Registrant address country: —

## Location

- City: Liberec
- Region: Liberec Region
- Country: Czech Republic
- Time zone: Europe/Prague

Approximate network location; registration and certificate addresses are not server-location evidence.

## Network classification

- Infrastructure type: —
- Datacenter / hosting: no
- Residential: no
- Mobile: yes
- Anycast: Unverified (not proof of unicast)
- Tor exit node: no
- VPN: no
- Proxy: no

## Risk assessment

- Assessment: Low Risk (0/100)
- Blocklist listings: 0
- Suspicious activity indicators: no
- Spam source: no

## Reverse DNS

- 90-181-66-137.rco.o2.cz
- Forward-confirmed: yes

## DNS posture

Mail authentication and CAA are optional domain policies, not IP-wide requirements.

- spf: Not checked
- dmarc: Not checked
- fcrDns: Not checked
- dnssec: Not checked
- caa: Not checked

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Source: IPDebrief, "90.181.66.137 IP intelligence", https://ipdebrief.com/90.181.66.137, updated 2026-11-12. Assessments are probabilistic.