AS4221 — DNIC-ASBLK-04214-04221

AS4221 announces 0 IPv4 prefixes covering 0 addresses and 2 IPv6 prefixes.

About this network

Autonomous System 4221 is part of DNIC-ASBLK-04214-04221, a block of AS numbers registered to the United States Department of Defense.

What it's used for

• DoD network infrastructure. The registration is a generic departmental block and does not identify a specific base, command, or unit.

Notable

• The DNIC prefix refers to the Defense Network Information Center, the registry function that historically administered DoD internet number resources.
• DoD holds AS numbers in contiguous blocks like this one rather than requesting them individually, so neighbouring numbers in the 4214-4221 range share the same registration.
• The AS carries no publicly announced IPv4 address space, which is common for DoD numbers reserved for internal or non-public use.

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

Announced prefixes

• 2001:480:52::/48
• 2001:480:95::/48

Upstream networks

• AS668 United States Department of Defense (DoD)

Adjacent networks

• AS668 United States Department of Defense (DoD)