AS7151 — COLOGIX-SV

Network type: hosting

AS7151 announces 3 IPv4 prefixes covering 28,672 addresses and 1 IPv6 prefixes.

About this network

COLOGIX-SV is operated by Cologix, Inc., a North American network-neutral colocation and interconnection company headquartered in Denver, Colorado. This AS carries its California footprint.

What it's used for

• Colocation, interconnection and cloud on-ramp services out of Cologix's Silicon Valley data centre campus in Santa Clara.
• Announces roughly 28,000 IPv4 addresses — 209.128.64.0/18 (ARIN netname COLOGIX-CA-1), 72.20.96.0/19 and 72.172.176.0/20 — plus an IPv6 /32.

Notable

• A colocation operator's own AS mostly carries facility services and address space assigned to colocation customers, not a residential or transit customer base; Cologix's core value is the meet-me room, where hundreds of carriers and cloud providers cross-connect.
• Cologix acquired its Santa Clara campus from vXchnge in 2021, but the AS number and the /18 behind it are considerably older, dating to ARIN registrations in 1996 and 1999 respectively — inherited address space that came along with the business.

Interesting

• The gap between a 1996 AS number and a 2021 data-centre acquisition is a good illustration of how legacy resources migrate: the routing identity survives multiple changes of owner and brand.

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

Announced prefixes

• 72.20.96.0/19
• 72.172.176.0/20
• 209.128.64.0/18
• 2607:fce0::/32

Upstream networks

• AS6461 Zayo Bandwidth
• AS174 Cogent Communications, LLC

Downstream networks

• AS17109 Calitech

Adjacent networks

• AS6461 Zayo Bandwidth
• AS174 Cogent Communications, LLC
• AS17109 Calitech