AS21874 — MMC

AS21874 announces 2 IPv4 prefixes covering 2,304 addresses and 0 IPv6 prefixes.

About this network

MMC is the autonomous system for Marsh & McLennan Companies, a global professional services firm.

What it's used for

• The address space is registered to Marsh Inc., a subsidiary of Marsh & McLennan, with netnames MMC-205-156 indicating internal corporate usage.
• The AS announces 2304 IPv4 addresses across 2 prefixes and maintains 2 observed neighbours, a ratio consistent with an internal corporate estate rather than a transit or access network.

Notable

• Registrants for both announced prefixes are Marsh Inc., aligning with the announcer identity of MMC.
• Marsh & McLennan Companies is the holding company for Marsh Inc., which provides risk and insurance services.
• The inventory consists of two contiguous IPv4 blocks: 205.156.184.0/21 and 205.156.183.0/24.

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

Announced prefixes

• 205.156.183.0/24
• 205.156.184.0/21

Upstream networks

• AS23498 Beanfield Technologies Inc.
• AS577 Bell Canada

Adjacent networks

• AS23498 Beanfield Technologies Inc.
• AS577 Bell Canada

Routing security

• RPKI: 2 valid, 0 invalid and 0 not-found announcements; 8 ROAs.
• ASPA: none published.
• IRR: 100% of announcements registered; 13 route objects.
• Listed in as-sets: AS-BTGB-CUST, AS-CDSI, AS-CWCUSTEU, AS-GLOBALONE-UK, AS-UDOS, AS-VODAFONE-NET-IN, AS-VSNL-IN, AS1273:AS-CWW, AS23498:AS-CDSI, AS23498:AS-CUSTOMERS, AS23498:AS-CUSTOMERS2, AS9498:AS-BHARTI-IN.