AS13541 — SIEMENS-DISW-WIV-B-ORW

AS13541 announces 7 IPv4 prefixes covering 198,656 addresses and 1 IPv6 prefixes.

About this network

Eight IPv6 prefixes at eight different lengths, which is what an aggregate with one hole punched in it looks like.

What it's used for

• An engineering software company's network. 198,656 addresses across seven IPv4 prefixes, eight IPv6 prefixes, and two observed BGP neighbours.

Notable

• The IPv6 announcements run 2620:107:f000::/41, /42, /43, /44, /45, /46, /47 and /48, each starting where the previous one ends.
• IPv4 netnames include a numbered SIEMENS-DISW series and two that carry their own address, ORW-139-181-12-0-22 and ORW-139-181-17-0-24.
• 192.94.38.0/23 is netname NET192, registrant Various Registries (Maintained by ARIN).
• One prefix's registry lookup failed, so nothing is known about its registration here.
• Eighteen addresses were queried for reverse DNS and none returned a name.

Interesting

• A run of prefixes each half the size of the last, laid end to end, is the minimal way to express one large block with a single small piece removed. Something inside that range is routed elsewhere, and the routing table has to spell out everything except it.
• A registrant naming several registries collectively marks address space older than the current allocation system, sitting in the same table as blocks the company clearly holds itself.
• The ORW prefix reappears in the AS handle, so the letters identify a site or business unit rather than the company.

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

Announced prefixes

• 134.86.0.0/16
• 137.202.0.0/16
• 139.181.12.0/22
• 139.181.17.0/24
• 147.34.0.0/16
• 192.94.36.0/24
• 192.94.38.0/23
• 2620:107:f000::/40

Upstream networks

• AS33490 Comcast Cable Communications, LLC
• AS3356 Level 3 Parent, LLC

Adjacent networks

• AS33490 Comcast Cable Communications, LLC
• AS3356 Level 3 Parent, LLC