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Autonomous System

AS12663

Fastweb

Announced IPs
493,056
CIDR prefixes
206
ASN
AS12663

Reputation · trust score

A transparent 0–100 signal. Every entity starts at a neutral baseline of 65; threat-intel blocklists, exposure, reverse-DNS, routing and allocation each adjust it up or down. Higher is more trustworthy.

57/100
Caution
How this score is built

Experimental · trust-vectors model v1.1.0 — a transparent heuristic, not a definitive verdict. How it works →

⚠ 2 MOAS prefixes — multiple origin ASNs detected

All MOAS anomalies →

A previously stable prefix originated by AS12663 is now also announced by another ASN (MOAS — Multiple-Origin AS), detected from our RIPE RIS collectors. Often benign (anycast, multi-homing, or a recent transfer) — but it can signal a route leak or prefix hijack, so it's worth inspecting.

PrefixOrigin ASNsLast detected (UTC)
139.47.192.0/18 AS1273, AS12663 2026-07-21 22:08:15
176.125.0.0/19 AS1273, AS12663 2026-07-21 22:08:15

Top CIDR ranges

CIDRIPsPTR DensityOrganizationCountryStateCity
145.230.0.0/16 65.5K
0.0%
Fastweb DE
46.108.0.0/17 32.8K
0.0%
Fastweb DE
192.125.128.0/17 32.8K
0.1%
Fastweb DE
46.108.0.0/18 16.4K
0.0%
Fastweb DE
46.108.128.0/18 16.4K
0.0%
Fastweb DE
108.179.64.0/18 16.4K
0.0%
Fastweb DE
130.195.64.0/18 16.4K
0.0%
Fastweb IT
130.195.128.0/18 16.4K
0.0%
Fastweb DE
195.232.192.0/18 16.4K
1.7%
Fastweb DE
195.233.192.0/18 16.4K
0.6%
Fastweb DE
208.53.128.0/18 16.4K
0.0%
Fastweb DE
37.25.192.0/19 8.2K
0.0%
Fastweb DE
46.108.64.0/19 8.2K
0.0%
Fastweb DE
46.190.160.0/19 8.2K
0.0%
Fastweb DE
47.73.32.0/19 8.2K
0.6%
Fastweb DE
85.205.32.0/19 8.2K
0.5%
Fastweb DE
85.205.64.0/19 8.2K
1.7%
Fastweb DE
85.205.128.0/19 8.2K
0.0%
Fastweb DE
85.205.192.0/19 8.2K
1.3%
Fastweb DE
108.179.64.0/19 8.2K
0.0%
Fastweb DE
176.125.0.0/19 8.2K
0.0%
Fastweb DE
195.232.160.0/19 8.2K
1.8%
Fastweb DE
195.232.192.0/19 8.2K
1.1%
Fastweb DE
195.233.0.0/19 8.2K
0.4%
Fastweb DE North Rhine-Westphalia Düsseldorf
37.25.128.0/20 4.1K
0.0%
Fastweb DE
37.25.176.0/20 4.1K
0.0%
Fastweb DE
37.25.192.0/20 4.1K
0.0%
Fastweb IE
37.25.224.0/20 4.1K
0.1%
Fastweb DE
46.108.16.0/20 4.1K
0.0%
Fastweb GB
46.108.48.0/20 4.1K
0.0%
Fastweb GB
46.108.96.0/20 4.1K
0.0%
Fastweb DE
46.108.144.0/20 4.1K
0.0%
Fastweb GB
46.108.176.0/20 4.1K
0.0%
Fastweb GB
46.108.192.0/20 4.1K
0.0%
Fastweb DE
46.108.240.0/20 4.1K
0.0%
Fastweb DE
46.190.192.0/20 4.1K
0.0%
Fastweb DE
46.190.224.0/20 4.1K
0.0%
Fastweb DE
47.73.0.0/20 4.1K
1.1%
Fastweb DE
47.73.64.0/20 4.1K
0.4%
Fastweb DE North Rhine-Westphalia Düsseldorf
47.73.96.0/20 4.1K
0.0%
Fastweb DE
85.205.0.0/20 4.1K
0.0%
Fastweb DE
85.205.112.0/20 4.1K
0.0%
Fastweb DE
85.205.208.0/20 4.1K
0.1%
Fastweb DE
85.205.224.0/20 4.1K
0.0%
Fastweb DE
108.179.96.0/20 4.1K
0.0%
Fastweb DE
130.195.32.0/20 4.1K
0.0%
Fastweb DE
139.47.160.0/20 4.1K
0.0%
Fastweb DE
139.47.224.0/20 4.1K
0.0%
Fastweb DE
195.232.128.0/20 4.1K
10.0%
Fastweb DE
195.232.224.0/20 4.1K
1.8%
Fastweb DE
195.233.128.0/20 4.1K
2.9%
Fastweb DE
37.25.128.0/21 2.0K
0.0%
Fastweb DE
37.25.136.0/21 2.0K
0.0%
Fastweb IE
37.25.152.0/21 2.0K
0.0%
Fastweb DE
37.25.160.0/21 2.0K
0.0%
Fastweb DE
37.25.224.0/21 2.0K
0.0%
Fastweb IT
37.25.232.0/21 2.0K
0.0%
Fastweb DE
37.25.248.0/21 2.0K
0.0%
Fastweb DE
46.108.32.0/21 2.0K
0.0%
Fastweb GB
46.108.120.0/21 2.0K
0.0%
Fastweb DE
46.108.136.0/21 2.0K
0.0%
Fastweb GB
46.108.168.0/21 2.0K
0.0%
Fastweb GB
46.108.192.0/21 2.0K
0.0%
Fastweb GB
46.108.208.0/21 2.0K
0.0%
Fastweb DE
46.108.224.0/21 2.0K
0.0%
Fastweb DE
46.108.248.0/21 2.0K
0.0%
Fastweb DE
46.190.128.0/21 2.0K
0.0%
Fastweb DE
46.190.152.0/21 2.0K
0.0%
Fastweb DE
46.190.208.0/21 2.0K
0.0%
Fastweb DE
46.190.232.0/21 2.0K
0.0%
Fastweb DE
46.190.240.0/21 2.0K
0.0%
Fastweb DE
47.73.8.0/21 2.0K
0.6%
Fastweb DE
47.73.88.0/21 2.0K
1.7%
Fastweb DE
47.73.96.0/21 2.0K
0.0%
Fastweb DE
47.73.120.0/21 2.0K
0.1%
Fastweb DE
47.73.216.0/21 2.0K
0.0%
Fastweb DE
47.73.224.0/21 2.0K
0.0%
Fastweb DE
62.213.136.0/21 2.0K
0.0%
Fastweb DE
62.213.144.0/21 2.0K
0.0%
Fastweb DE
85.205.16.0/21 2.0K
0.0%
Fastweb DE
85.205.104.0/21 2.0K
4.2%
Fastweb DE
85.205.168.0/21 2.0K
0.0%
Fastweb DE
85.205.192.0/21 2.0K
0.2%
Fastweb DE
89.32.48.0/21 2.0K
0.0%
Fastweb DE
92.114.8.0/21 2.0K
0.0%
Fastweb DE
108.179.112.0/21 2.0K
0.0%
Fastweb DE
130.195.200.0/21 2.0K
0.0%
Fastweb DE
139.47.184.0/21 2.0K
0.0%
Fastweb DE
139.47.216.0/21 2.0K
0.0%
Fastweb DE
139.47.224.0/21 2.0K
0.0%
Fastweb DE
139.47.248.0/21 2.0K
0.0%
Fastweb ES
176.125.8.0/21 2.0K
0.0%
Fastweb DE
176.125.16.0/21 2.0K
0.0%
Fastweb DE
195.232.152.0/21 2.0K
0.0%
Fastweb DE
195.232.240.0/21 2.0K
3.5%
Fastweb DE
195.233.56.0/21 2.0K
0.7%
Fastweb DE
37.25.172.0/22 1.0K
0.0%
Fastweb DE
37.25.208.0/22 1.0K
0.0%
Fastweb IE
37.25.212.0/22 1.0K
0.0%
Fastweb ES
37.25.216.0/22 1.0K
0.0%
Fastweb ES

BGP Announced Prefixes

Live BGP anomalies →

Prefixes AS12663 actually originates in BGP, observed across our RIPE RIS collectors. This live routing view can differ from the registry allocation above.

PrefixAnnouncement samplesLast seen
176.125.0.0/19 22,566 2026-07-21 21:27:39
47.73.96.0/21 17,008 2026-07-21 21:36:23
195.233.250.0/24 17,005 2026-07-21 21:36:36
47.73.252.0/22 16,952 2026-07-21 21:36:30
47.73.224.0/21 16,854 2026-07-21 21:36:23
195.233.128.0/22 13,825 2026-07-21 21:36:24
37.25.176.0/20 13,823 2026-07-21 21:36:24
195.232.224.0/22 13,819 2026-07-21 21:36:24
47.73.44.0/22 13,763 2026-07-21 21:36:36
85.205.228.0/23 13,753 2026-07-21 21:36:24
195.233.144.0/24 13,747 2026-07-21 21:36:36
46.108.213.0/24 13,722 2026-07-21 21:36:24
47.73.88.0/22 13,670 2026-07-21 21:36:24
195.232.248.0/24 13,666 2026-07-21 21:36:24
47.73.104.0/23 13,659 2026-07-21 21:36:36
139.47.208.0/22 13,654 2026-07-21 21:36:24
47.73.8.0/21 13,642 2026-07-21 21:36:36
47.73.108.0/23 13,621 2026-07-21 21:36:36
85.205.150.0/23 13,316 2026-07-21 21:36:24
85.205.224.0/22 13,267 2026-07-21 21:36:22
139.47.175.0/24 13,256 2026-07-21 21:36:24
47.73.91.0/24 13,207 2026-07-21 21:36:23
195.233.57.0/24 13,179 2026-07-21 21:36:30
195.233.59.0/24 13,143 2026-07-21 21:36:23
47.73.90.0/24 13,135 2026-07-21 21:36:30
195.232.128.0/17 12,918 2026-07-21 21:36:24
37.25.128.0/21 12,877 2026-07-21 21:36:36
145.230.0.0/16 12,874 2026-07-21 21:36:36
85.205.92.0/22 12,815 2026-07-21 21:36:18
195.233.63.0/24 12,805 2026-07-21 21:36:24
85.205.32.0/23 12,799 2026-07-21 21:36:30
85.205.94.0/24 12,795 2026-07-21 21:36:20
46.108.208.0/24 12,787 2026-07-21 21:36:24
85.205.225.0/24 12,782 2026-07-21 21:36:24
85.205.227.0/24 12,779 2026-07-21 21:36:18
85.205.95.0/24 12,761 2026-07-21 21:36:22
139.47.189.0/24 12,752 2026-07-21 21:36:24
46.190.225.0/24 12,745 2026-07-21 21:36:24
139.47.226.0/24 12,740 2026-07-21 21:36:36
85.205.233.0/24 12,730 2026-07-21 21:36:36
85.205.208.0/20 12,719 2026-07-21 21:36:30
85.205.121.0/24 12,718 2026-07-21 21:36:24
85.205.151.0/24 12,705 2026-07-21 21:36:30
47.73.36.0/23 12,695 2026-07-21 21:36:36
85.205.36.0/22 12,670 2026-07-21 21:36:36
47.73.89.0/24 12,661 2026-07-21 21:36:23
85.205.206.0/23 12,652 2026-07-21 21:36:30
176.125.23.0/24 12,647 2026-07-21 21:36:36
85.205.150.0/24 12,640 2026-07-21 21:36:30
192.125.175.0/24 12,639 2026-07-21 21:36:30

Showing top 50 of 175 announced prefixes by sample volume.

Frequently Asked Questions

What is AS12663?

AS12663 is an Autonomous System Number assigned to Fastweb. An ASN identifies a network that controls a specific set of IP addresses and determines how traffic is routed across the internet via BGP (Border Gateway Protocol).

How many IP addresses does AS12663 announce?

AS12663 announces 493.1K IPv4 addresses distributed across 206 routed CIDR prefixes. The network is registered in Italy.

Who operates AS12663?

AS12663 is operated by Fastweb. The organization is based in Italy. You can view all IP ranges and related ASNs on the organization page.

What country is AS12663 registered in?

AS12663 is registered in Italy. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.

Last updated: 2026-07-21 22:10:34 UTC
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