Skip to main content
Autonomous System

AS26551

Sargent & Lundy Engineers

Announced IPs
65,536
CIDR prefixes
1
ASN
AS26551

Reputation · trust score

A transparent 0–100 signal. Every entity starts at a neutral baseline of 65; threat-intel blocklists, exposure, reverse-DNS, routing and allocation each adjust it up or down. Higher is more trustworthy.

65/100
Moderate
How this score is built

Experimental · trust-vectors model v1.2.0 — a transparent heuristic, not a definitive verdict. How it works →

Top CIDR ranges

CIDRIPsPTR DensityOrganizationCountryStateCity
151.154.0.0/16 65.5K
98.0%
Sargent & Lundy Engineers US Illinois Chicago

BGP Announced Prefixes

Live BGP anomalies →

Prefixes AS26551 actually originates in BGP, observed across our RIPE RIS collectors. This live routing view can differ from the registry allocation above.

PrefixAnnouncement samplesLast seen
151.154.103.0/24 7,810 2026-07-26 11:51:03
151.154.223.0/24 7,799 2026-07-26 11:51:03
151.154.128.0/20 5,090 2026-07-26 11:53:31
151.154.84.0/22 4,352 2026-07-26 11:53:20
151.154.0.0/16 4,283 2026-07-26 11:53:20

Frequently Asked Questions

What is AS26551?

AS26551 is an Autonomous System Number assigned to Sargent & Lundy Engineers. An ASN identifies a network that controls a specific set of IP addresses and determines how traffic is routed across the internet via BGP (Border Gateway Protocol).

How many IP addresses does AS26551 announce?

AS26551 announces 65.5K IPv4 addresses distributed across 1 routed CIDR prefixes. The network is registered in United States.

Who operates AS26551?

AS26551 is operated by Sargent & Lundy Engineers. The organization is based in United States. You can view all IP ranges and related ASNs on the organization page.

What country is AS26551 registered in?

AS26551 is registered in United States. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.

Last updated: 2026-07-26 12:25:31 UTC
Share