AS12551 — AS-ENEL-

AS12551 announces 17 IPv4 prefixes covering 72,192 addresses and 0 IPv6 prefixes.

About this network

Italy's electricity utility announcing 35 prefixes, nine of which reassemble into a single /19.

What it's used for

• Corporate connectivity for a national electricity company. 72,192 addresses in 35 IPv4 prefixes, five observed BGP neighbours, and no IPv6 announced.

Notable

• Every block carries the same netname, ENEL-NET, registered to ENEL S.p.A with an Enel Energia abuse department as contact.
• Nine of the announcements — 146.133.0.0/23, 2.0/23, 4.0/22, 8.0/21, 16.0/22, 20.0/22, 24.0/22, 28.0/23 and 30.0/23 — cover 146.133.0.0/19 exactly, with nothing left over and nothing overlapping.
• The inventory spans two unrelated ranges, 146.133 and 158.47, cut into everything from a /18 down to /23s.
• Some blocks are registered to an ENEL LIR and others directly to ENEL S.p.A.

Interesting

• Announcing nine prefixes where one /19 would do is the recurring artefact of this range, and it is not a mistake so much as a habit. Each piece was probably turned up separately, for a different site or purpose, and nobody ever went back to collapse them once the whole range was in use.
• Thirty-five prefixes for five neighbours is the opposite of a transit network. A utility's network follows its physical estate — substations, plants, regional offices — and the fragmentation is that estate showing through into BGP.
• ENEL also appears in this range as a customer: AS12533, a small Italian ISP, has a host named enel in its reverse zone. Large utilities show up in the routing table both as themselves and as somebody else's dedicated circuit.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy.

Announced prefixes

• 146.133.0.0/18
• 146.133.64.0/19
• 146.133.96.0/20
• 146.133.112.0/21
• 146.133.120.0/22
• 146.133.125.0/24
• 146.133.126.0/24
• 146.133.128.0/19
• 146.133.240.0/24
• 158.47.0.0/22
• 158.47.4.0/24
• 158.47.6.0/23
• 158.47.8.0/23
• 158.47.14.0/23
• 158.47.16.0/20
• 158.47.32.0/19
• 158.47.64.0/18

Upstream networks

• AS3269 Telecom Italia S.p.A.
• AS15830 Equinix (EMEA) Acquisition Enterprises B.V.
• AS30722 Fastweb SpA
• AS12085 Equinix, Inc.
• AS1273 IDDQD-AS

Adjacent networks

• AS3269 Telecom Italia S.p.A.
• AS15830 Equinix (EMEA) Acquisition Enterprises B.V.
• AS30722 Fastweb SpA
• AS12085 Equinix, Inc.
• AS1273 IDDQD-AS