AS3909 — CENTURYLINK-LEGACY-QWEST-VDOC

AS3909 announces 4 IPv4 prefixes covering 6,912 addresses and 0 IPv6 prefixes.

About this network

A CenturyLink Communications, LLC autonomous system (CENTURYLINK-LEGACY-QWEST-VDOC) inherited from Qwest, now part of Lumen Technologies.

What it's used for

• Announcing a small set of prefixes — roughly 7,000 IPv4 addresses — behind Lumen's main backbone, AS209, which is its only upstream.
• Functionally a stub: a handful of routed blocks rather than a transit network in its own right.

Notable

• Despite the carrier name, this ASN is not a backbone. Lumen's actual transit business runs on AS209 and AS3356; AS3909 carries a narrow slice of legacy Qwest routing.
• The VDOC element of the handle is not documented publicly and should not be read as identifying any particular customer or division.

Interesting

• Lumen holds a long tail of these legacy Qwest and CenturyLink ASNs, absorbed through decades of mergers. The naming convention — CENTURYLINK-LEGACY- — is the company labelling its own acquisition history in the registry.

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

Announced prefixes

• 8.64.40.0/21
• 65.123.252.0/23
• 67.13.228.0/24
• 204.193.208.0/20

Upstream networks

• AS209 CenturyLink Communications, LLC

Adjacent networks

• AS209 CenturyLink Communications, LLC