AS63Massachusetts Institute of Technology
As of 13th October 2026, AS63 (Massachusetts Institute of Technology), a network registered in the United States with ARIN, originates 6 IPv4 prefixes covering 67.8k addresses. By IPv4 address space that makes it the 3,233rd-largest of the 79,585 networks we see originating IPv4, and the 1,077th-largest of 18,443 in the United States. It is seen behind 3 upstream networks, most often AS13789 (Unitas Global) and AS11164 (Internet2 I2PX). None of its announcements have a valid RPKI ROA. 100% 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 AS63 is seen behind, one and two hops out, drawn from real AS paths.
Networks observed one and two hops upstream of AS63 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
6
adjacent networks
- Upstreams
- 350%
- Peers
- 350%
- Downstreams
- 00%
Networks carrying this one's traffic toward the rest of the internet.
| Network | Country | Relationship | Paths | Vantage pts |
|---|---|---|---|---|
| AS13789Unitas Global | Peer | 426 | 71 | |
| AS11164Internet2 I2PX | Peer | 48 | 8 | |
| AS11537Internet2 | Peer | 12 | 2 |
Prefixes
The largest blocks AS63 originates, widest first.
| Prefix | Addresses | Visibility |
|---|---|---|
| 129.55.0.0/16 | 65.5k | 81/81 |
| 192.5.136.0/22 | 1k | 81/81 |
| 192.5.140.0/23 | 512 | 81/81 |
| 129.55.201.0/24 | 256 | 81/81 |
| 192.26.149.0/24 | 256 | 81/81 |
| 192.26.150.0/24 | 256 | 81/81 |
Routing health
How AS63'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%6
Propagation
- Globally propagated90% of full-feed peers or more100.0%6
- Partially propagated40% to 90%0.0%0
- Seen by few peersUnder 40%0.0%0
Prefix sizes
Recent changes
Announcements that started or stopped since 13th Sept 2026.
No announcement by AS63 started or stopped in this period.
Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.