AS15698 — ENBW-AG

AS15698 announces 1 IPv4 prefixes covering 2,048 addresses and 1 IPv6 prefixes.

About this network

One IPv4 block and sixteen IPv6 ones, announced as a staircase that doubles at every step.

What it's used for

• An energy utility's network. One IPv4 prefix and sixteen IPv6 prefixes announced from Germany, two thousand and forty-eight addresses, across two observed BGP neighbours.

Notable

• The IPv6 announcements start at a /47 and step up through /46, /45, /44, /43, /42, /41, /39, each one exactly twice the size of the last, with a /40 alongside them.
• That is what covering a range whose boundaries do not fall on a single block looks like: the range gets tiled by the largest piece that fits at each point, and the result is a doubling sequence.
• The whole IPv4 holding is a single /21, registered under one netname with the company and an abuse role.
• There are eight times as many IPv6 routes as IPv4 addresses would suggest, on a network with two upstreams.
• Three addresses were queried for reverse DNS and none returned a name.

Interesting

• A staircase is not a mistake, it is arithmetic. Every network that announces part of an allocation produces one, and the number of steps is fixed by where the range starts and stops rather than by anything the operator chose.
• A utility with two thousand IPv4 addresses and a large IPv6 allocation is a corporate network that arrived late enough to be given room in the newer family and early enough to be starved in the old one.

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

Announced prefixes

• 195.35.72.0/21
• 2a0b:f400::/32

Upstream networks

• AS8881 1&1 Versatel GmbH
• AS41998 NetCom BW GmbH

Adjacent networks

• AS8881 1&1 Versatel GmbH
• AS41998 NetCom BW GmbH