181.203.128.0/18
At a glance
Addresses
/18 block
Visibility
80 of 81 vantage points
RPKI
Registry
CAAllocated 16th July 2026
AS paths to this prefix
One real path per vantage point, fanning out from the origin. Where two reach the prefix the same way, those hops are drawn once. Open a path to follow it hop by hop.
- Sao Paulo576935280This path
- London, UK5769129935280This path
- Singapore57696939132337This path
- Oregon, US5769693920130This path
- Amsterdam57691299250918298This path
Each row is one path genuinely present in the routing table at our last snapshot, read outward from the origin to the vantage point that saw it. Open a row to follow that one path hop by hop. A heavier line in the graph means more vantage points reach the prefix that same way.
Route visibility
99%
Seen by 80 of 81 full-feed vantage points
Globally propagatedObserved at 5 of our collectors.
What this percentage counts
The denominator counts only full-feed peers — peers carrying a substantially complete routing table at the moment of the snapshot. IXP route-server peers usually feed partial tables and are excluded, because including them would make a normally propagated prefix look as though half the internet could not see it.
It measures how widely an announcement has spread across the networks we can observe. It says nothing about whether the prefix is reachable from any particular place, or how it performs.
Registry and RPKI
- RIR
- ARIN — North America
- Country
- Canada
- Allocated
- 16th July 2026
- Allocation block
- 181.203.0.0/16
- Status
- allocated
- Origin validation
- Valid
A ROA exists that authorises this origin AS to announce this prefix at this length.
Prefix hierarchy
Announcements above, below and beside this one in the real routing table.
Left to right is specificity: a shorter mask covering more address space, then this prefix, then the announcements carved out inside it. Only the first few of each are drawn — the tables below list them all.
Covering announcements
| Prefix | Addresses | Origin | Visibility |
|---|---|---|---|
| 181.203.0.0/16 | 65.5k | AS5769Videotron Ltee | 80/81 |
More specific announcements
Nothing inside this block is announced separately.
Sibling prefixes
| Prefix | Addresses | Origin | Visibility |
|---|---|---|---|
| 181.203.192.0/18 | 16.4k | AS5769Videotron Ltee | 80/81 |
History
- AS576922nd September 2026 — present
Why these dates start where they do
A first-seen date is the first time we saw that origin, not the first time it appeared in BGP. Our history is forward-only with no backfill, so it says nothing about the period before we started collecting — treat the earliest dates with suspicion.
Open 181.203.128.0/18 in the calculator/18 reference
Routing data derived from RouteViews MRT archives and public registry data.