$ query “AS5721” --type=asn → 1 result(s)
AS5721 — NDU-NET
National Defense University
AS5721 is an educational stub network run by National Defense University, established in the United States in 1995. The network announces 512 IPv4 addresses. No IPv6 support — it's 2026, just saying.
- Pioneer — Registered before the year 2000
Basic Information
- Country
- 🇺🇸 United States
- Category
- Education/Research
- Network Role
- Stub Network
- Data Origin
- Authoritative — Metadata from authoritative RIR registry (ARIN, RIPE, APNIC, etc.)
- Registered
- September 06, 1995
- Last Changed
- March 04, 2026
- Last Seen
- March 05, 2026
Prefix Summary
- IPv4 Prefixes (raw / aggregated)
- 2 / 1
- IPv6 Prefixes (raw / aggregated)
- 0 / 0
- IPv4 Addresses
- 512
- Largest IPv4 Prefix
- /23 (512 addresses)
- Geolocated Countries
- 🇺🇸 US (1 IPs)
- Prefix Changed
- March 04, 2026
Reputation
- Reputation
- Pristine — 0 flagged IPs out of 512 total (0.00%)
Connectivity Summary
- Upstream Providers
- 2 upstream autonomous systems providing transit
- Peers
- 0 autonomous systems exchanging traffic without transit fees
- Downstream Customers
- 0 downstream autonomous systems buying transit
- Degree
- 2 unique BGP neighbors (providers + customers + peers)
- Reach
- 0 — customer cone size measuring network influence
- Degree Rank
- #29 701
Upstream Providers (2)
Prefix Lists
IPv4 Prefixes (2 total)
- 216.21.18.0/23 (512 addresses)