AS15490 — SHANEMCC

AS15490 announces 1 IPv4 prefixes covering 512 addresses and 12 IPv6 prefixes.

About this network

Nineteen IPv6 routes and five hundred IPv4 addresses, from a network with one upstream.

What it's used for

• A one-person company's network. One IPv4 /23 and nineteen IPv6 prefixes announced from the United Kingdom, five hundred addresses, through a single observed BGP neighbour.

Notable

• The IPv6 announcements form a doubling staircase: a /32, then a /33, /35, /38, /41, /43, /47, /48, /46, /45 and more, each one covering the space the previous ones left.
• The single IPv4 block is registered to a limited company; the abuse contact is an individual's name rather than a role.
• Two sampled addresses answer with the address in dashes under the company domain.
• The third answers under a completely different domain, with a three-letter label used for a relay host that keeps a connection open on a user's behalf.
• Three addresses were queried for reverse DNS and all three returned a name.

Interesting

• Nineteen IPv6 routes from five hundred IPv4 addresses inverts the usual proportions. Most networks this size announce one IPv6 prefix if any; this one announces more than many national carriers.
• The staircase is how you announce a range piece by piece when the pieces are not a power of two. Every step doubles, so ten routes cover what no single prefix could.
• A relay host named in reverse DNS points at chat infrastructure, which is a use that predates most of what runs on the internet now and has never quite gone away.

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

Announced prefixes

• 185.141.254.0/23
• 2a07:2780::/31
• 2a07:2781:a4a4::/46
• 2a07:2781:a4a8::/45
• 2a07:2781:a4b0::/44
• 2a07:2781:a4c0::/42
• 2a07:2781:a500::/40
• 2a07:2781:a600::/39
• 2a07:2781:a800::/37
• 2a07:2781:b000::/36
• 2a07:2781:c000::/34
• 2a07:2782::/31
• 2a07:2784::/30

Upstream networks

• AS60004 ShaneMcC Ltd

Adjacent networks

• AS60004 ShaneMcC Ltd

Routing security

• RPKI: 3 valid, 0 invalid and 0 not-found announcements; 7 ROAs.
• ASPA: none published.
• IRR: 100% of announcements registered; 9 route objects.
• Listed in as-sets: AS-BTN-CUSTOMERS, AS-IFOG, AS-IFOG, AS-SHANEMCC.