171.251.234.21
171.251.234.21 is an IPv4 address operated by IRT-VNNIC-AP (AS7552), geolocated to Ho Chi Minh City, Vietnam. Its reverse DNS name is dynamic-adsl.viettel.vn. As of October 6, 2026, IPDebrief rates it Low Risk (0/100); no anonymizing service was detected.
## IP Intelligence Briefing: 171.251.234.21/32
Classification: Low Risk (Risk Score: 25)
Status: Active Defensive Assessment Complete
Network Identity:
IP 171.251.234.21 is registered to Vietnam (VN), Ho Chi Minh City, under ASN 7552 (IRT-VNNIC-AP), organizational block VIETTEL-VN. The address belongs to CIDR block 171.224.0.0/11, classified as a provider infrastructure. DNS resolution maps to dynamic-adsl.viettel.vn with forward resolution confirmed.
Threat Assessment:
The IP maintains a low-risk posture with a risk score of 25. No threat indicators were observed during profiling. The address is not identified as a Tor exit node, known attacker, spam source, or proxy. Blacklist enumeration returned zero hits across major feeds. Control plane analysis identified one DNSBL listing among eight total lists checked, indicating minimal operator-level risk.
Network Behavior:
Services enumeration revealed no open ports and no active services. The network role is classified as provider-type infrastructure with firewalling enabled. Historical signal observations (16 total) indicate clean classification across recent assessments. No persistent malicious behavior was detected, with zero threat observation count and zero threat persistence days recorded.
Geolocation Confidence:
Geolocation data shows 52% confidence placing the address in Vietnam at coordinates (14.06, 108.28), with 600km accuracy radius. Multiple signal sources corroborated the country-level assessment.
Subnet Analysis:
The /24 neighborhood (171.251.234.21/24) exhibits zero abuse density with clean classification. No sibling IPs within the subnet showed elevated threat characteristics. Zero high-risk and zero medium-risk neighbors detected among the 254 available addresses.
Associated Entities:
Nine relationships were identified, including four same-network associations with VIETTEL-VN and five DNS associations mapping to dynamic-adsl.viettel.vn. No certificate correlations or known campaign affiliations were discovered.
Recommended Actions:
No immediate blocking or filtering actions required. The IP presents as legitimate provider infrastructure with low-risk characteristics. Standard monitoring practices apply.
This summary was generated by AI and may contain inaccuracies. Verify critical details independently.
🏢 Ownership & Registration
| Organization | IRT-VNNIC-AP |
| ASN | AS7552 |
| Network Name | VIETTEL-VN |
| CIDR Block | 171.224.0.0/11 |
| RIR | APNIC |
| Country | VN |
| Abuse Contact | Available via RDAP |
🌐 DNS Intelligence
| PTR | dynamic-adsl.viettel.vn |
| Forward Confirmed | No — PTR hostname does not resolve back to this IP (weak signal) |
| Forward Hostnames | dynamic-adsl.viettel.vndynamic-ip-adsl.viettel.vn |
🔐 DNS Hygiene
| Hygiene Score | 40% (Fair) |
| SPF | 2/2 domains |
| DMARC | 2/2 domains |
| FCrDNS | Not verified |
| DNSSEC | Not signed |
| CAA | Not configured |
| Domains Checked | 2 domains |
☁️ Network Classification
| Infrastructure | Unknown |
| Service Purpose | Firewalled / No Services |
| Network Tier | Unknown — Insufficient routing data to classify |
🔌 Services & Open Ports
| Port | Service | Protocol | Banner |
|---|---|---|---|
| No open ports detected | |||
| Closed Ports | 22, 25, 80, 443, 3389, 8080, 8443 (0 open / 7 scanned) | ||
| Server | — |
| HTTP Title | — |
🔐 TLS Certificate
| SANs | None |
| Valid From | — |
| Valid Until | — |
🛡️ Public Network Snapshot
| Origin ASN | AS7552 |
| Network Prefix | 171.251.232.0/22 |
| Route mapping | Found |
🎯 Confidence Breakdown
Per-dimension confidence scores based on source diversity and data freshness
| Dimension | Score | Sources | Observations |
|---|---|---|---|
| threat | 25% | 1 | 1 |
| routing | 25% | 1 | 1 |
| services | 25% | 1 | 1 |
| ownership | 0% | 0 | 0 |
| reputation | 0% | 0 | 0 |
| geolocation | 25% | 1 | 1 |
| Overall | 16% | 4 | 4 |
| Data Coherence | Consistent (100%) |
| Attribution | Moderate (50%) |
| OwnershipFCrDNSGeo ConsensusGeo PlausibleIRR MatchRPKI Valid |
📅 Observation Timeline 🔄 Live
| First Seen | 2026-07-08 13:02:37 UTC |
| Last Seen | 2026-10-06 09:30:14 UTC |
| Profile Built | 2026-10-06 09:30:53 UTC |
| Data Freshness | Live |
| Signal Types | 18 |
| Total Observations | 22 |
Full dossier details are available via our API.
❓ Frequently Asked Questions About 171.251.234.21
Who owns the IP address 171.251.234.21?
171.251.234.21 is registered to IRT-VNNIC-AP. The address falls within the 171.224.0.0/11 network block. Registration is held at APNIC.
Where is 171.251.234.21 located?
Geolocation data places 171.251.234.21 in Ho Chi Minh City, Ho Chi Minh, Vietnam. The local time zone is Asia/Ho_Chi_Minh. IP geolocation is approximate and indicates the network's registered or routed location rather than a precise physical address.
Is 171.251.234.21 malicious or safe?
171.251.234.21 currently carries a low risk assessment, meaning no significant threat indicators have been observed. This assessment is generated from continuously collected signals and can change over time.
What is the hostname for 171.251.234.21?
The reverse DNS (PTR) record for 171.251.234.21 is dynamic-adsl.viettel.vn. This hostname is not forward-confirmed, so it should be treated as a weak signal.