AS38University of Illinois
United StatesRegistryARINTypeEyeballAs of 25th October 2026, AS38 (University of Illinois), an access network registered in the United States with ARIN, originates 6 IPv4 prefixes covering 218k addresses and 3 IPv6 prefixes. By IPv4 address space that makes it the 1,243rd-largest of the 79,676 networks we see originating IPv4, and the 346th-largest of 18,493 in the United States. It is seen behind 2 upstream networks, most often AS40387 (University of Illinois) and AS11537 (Internet2). None of its announcements have a valid RPKI ROA. 78% of its routes reach at least 90% of full-feed peers.
At a glance
IPv4 prefixes
IPv6 prefixes
IPv4 addresses
IPv6 /64s
Upstream graph
The networks AS38 is seen behind, one and two hops out, drawn from real AS paths.
Networks observed one and two hops upstream of AS38 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.
Neighbouring networks
4
adjacent networks
- Upstreams
- 250%
- Peers
- 250%
- Downstreams
- 00%
Networks carrying this one's traffic toward the rest of the internet.
| Network | Country | Relationship | Paths | Vantage pts |
|---|---|---|---|---|
| AS40387University of Illinois | US | Peer | 493 | 139 |
| AS11537Internet2 | US | Peer | 4 | 2 |
Prefixes
The largest blocks AS38 originates, widest first.
| Prefix | Addresses | Visibility |
|---|---|---|
| 128.174.0.0/16 | 65.5k | 76/76 |
| 130.126.0.0/16 | 65.5k | 76/76 |
| 192.17.0.0/16 | 65.5k | 76/76 |
| 72.36.64.0/18 | 16.4k | 76/76 |
| 72.36.96.0/20 | 4.1k | 2/76 |
| 72.36.80.0/23 | 512 | 2/76 |
| 2600:3900::/28 | 68.7B × /64 | 63/63 |
| 2620:0:e00::/48 | 65.5k × /64 | 63/63 |
| 2620:0:e01::/48 | 65.5k × /64 | 63/63 |
Routing health
How AS38's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.
RPKI origin validation
- Valid0.0%0
- Invalid0.0%0
- No ROA100.0%9
Propagation
- Globally propagated90% of full-feed peers or more77.8%7
- Partially propagated40% to 90%0.0%0
- Seen by few peersUnder 40%22.2%2
Prefix sizes
IPv4 — 6 prefixes
IPv6 — 3 prefixes
- /2868.7B × /6433.3%1
- /4865.5k × /6466.7%2
Recent changes
Announcements that started or stopped since 25th Sept 2026.
No announcement by AS38 started or stopped in this period.
Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.