CUST4
BGP inherited
Cluster stats
| Netblocks | 7 · 1,785 IPv4 addresses |
| Registered in | France (6) · Czechia (1) |
| All fragments | 10 blocks across 4 clusters |
| Cluster ID | 210093865 |
| Registry | RIPE |
| Customers | find customers using this network → |
Evidence & provenance ?
| Attribution | BGP parent (inherited) |
| Shared handles | clustered on 4 shared RIR contact/maintainer handles |
| Registry names | 1 distinct registrant name across these blocks |
| full provenance (JSON) → · how attribution works | |
Footprint over time
5 weekly snapshots · JSON
7
0 netblocks since 2026-07-05
2026-07-05
peak 7
2026-07-19
IP Ranges (7)
⬇ export CSV| CIDR | Org name | Registry | Status | Confidence |
|---|---|---|---|---|
| 5.253.135.0/24 | CUST4 | RIPE | ASSIGNED PA | ● low |
| 139.28.118.0/24 | CUST4 | RIPE | ASSIGNED PA | ● low |
| 185.19.227.0/24 | CUST4 | RIPE | ASSIGNED PA | ● low |
| 185.148.255.0/24 | CUST4 | RIPE | ASSIGNED PA | ● low |
| 185.149.219.0/24 | CUST4 | RIPE | ASSIGNED PA | ● low |
| 185.232.27.0/24 | CUST4 | RIPE | ASSIGNED PA | ● low |
| 185.243.19.0/24 | CUST4 | RIPE | ASSIGNED PA | ● low |
Possibly related to this organisation
what's this?Same name family
Separately-registered clusters whose names share “CUST4” — often
per-country or per-system registrations of the same brand, occasionally a different
organisation sharing the name. Not counted in this organisation's own footprint.
- CUST4-30 1 blocks
- CUST4-29 1 blocks
- Cust4-nats 1 blocks
Sub-allocations under carriers
IP blocks an ISP reassigned to a similarly-named customer — decoded from the ISP's own
naming convention, not a direct registration.
- NSYSCZ_CUST4 via "N_SYS s.r.o." sub-allocation
- Itsjefen via ITsjefen AS sub-allocation
- CUST4210-OWNIT-SE via Telenor Sverige AB sub-allocation
- CUST4693-OWNIT-SE via Telenor Sverige AB sub-allocation
- CUST4832-OWNIT-SE via Telenor Sverige AB sub-allocation
- CUST4150-OWNIT-SE via Telenor Sverige AB sub-allocation
- CUST4756-OWNIT-SE via Telenor Sverige AB sub-allocation
- CUST4461-OWNIT-SE via Telenor Sverige AB sub-allocation
Network trust
what's this?
RPKI hygiene: B
how networks compare →
85.7%
of checked blocks have valid RPKI ROA coverage
(6 of 7)
Possible discrepancies (6)
These blocks are registered to CUST4 but cryptographically authorized for a different, unrelated network (4 distinct holders) — often M&A history, multi-homing, or outsourced/managed hosting, occasionally worth a closer look.
| 139.28.118.0/24 /24 | authorized for AS209621 — DOBNET, z.s. |
| 185.148.255.0/24 /24 | authorized for AS44821 — Koesio Nord Ouest SAS |
| 185.19.227.0/24 /24 | authorized for AS25540 — Alphalink SASU |
| 185.243.19.0/24 /24 | authorized for AS25540 — Alphalink SASU |
| 185.149.219.0/24 /24 | authorized for AS197033 — KOESIO Networks SAS |
| 185.232.27.0/24 /24 | authorized for AS197033 — KOESIO Networks SAS |
NIC Handles
DUMY-RIPE
DUMY-RIPE
MNT-CPRO
mnt-cz-dobnet-1