Autonomous System

AS20057 · AT&T Enterprises, LLC

Overview

AS20057 is announced on the Internet: RIPE RIS route collectors currently see 1,449 IPv4 prefixes and 161 IPv6 prefixes originated by this network. Together, its IPv4 prefixes cover 3,981,312 addresses, with overlapping prefixes counted once. In the paths the collectors record, it has 1 upstream neighbour (transit providers or peers) and 1 downstream neighbour (customers or networks it carries). Its most visible upstream is AT&T Enterprises, LLC (AS7018). AS20057 was assigned by ARIN, and its registration country is United States.

Source: RIPEstat (RIPE NCC), RIS route collectors. Read on October 16, 2026 at 9:49 PM UTC. This page is refreshed at most every 12 hours.

Go further

Trace a route to this network Open in the BGP viewer WHOIS of 166.128.0.1

The trace goes to 166.128.0.1, the first address of 166.128.0.0/14. An address picked inside a prefix may not answer (nothing listens there, or the network filters probes): the trace then shows the path up to the last network that replies.

Announced prefixes

IPv4 prefixes (1,449 prefixes)

Prefix	Addresses
12.72.0.0/17	32,768
12.72.0.0/19	8,192
12.72.32.0/21	2,048
12.72.40.0/21	2,048
12.72.48.0/21	2,048
12.72.56.0/21	2,048
12.72.64.0/22	1,024
12.72.68.0/22	1,024
12.72.72.0/22	1,024
12.72.76.0/23	512
12.72.82.0/23	512
12.72.86.0/24	256
12.72.88.0/23	512
12.72.90.0/23	512
12.72.92.0/22	1,024
12.72.96.0/22	1,024
12.72.100.0/23	512
12.72.102.0/24	256
12.72.104.0/21	2,048
12.72.113.0/24	256
12.72.114.0/23	512
12.72.116.0/23	512
12.72.119.0/24	256
12.72.120.0/24	256
12.72.122.0/24	256
12.72.123.0/24	256
12.72.126.0/24	256
12.72.128.0/17	32,768
12.72.128.0/24	256
12.72.129.0/24	256
12.72.130.0/24	256
12.72.132.0/24	256
12.72.134.0/23	512
12.72.136.0/21	2,048
12.72.144.0/21	2,048
12.72.160.0/20	4,096
12.72.192.0/19	8,192
12.72.224.0/20	4,096
12.72.240.0/21	2,048
12.72.248.0/24	256
12.72.251.0/24	256
12.72.252.0/24	256
12.72.253.0/24	256
12.73.0.0/17	32,768
12.73.0.0/19	8,192
12.73.32.0/19	8,192
12.73.64.0/18	16,384
66.102.186.0/24	256
107.72.162.0/24	256
107.72.163.0/24	256
107.72.164.0/24	256
107.72.165.0/24	256
107.72.174.0/24	256
107.72.176.0/24	256
107.72.177.0/24	256
107.72.178.0/24	256
107.72.225.0/24	256
107.77.64.0/24	256
107.77.65.0/24	256
107.77.66.0/24	256
107.77.67.0/24	256
107.77.68.0/24	256
107.77.69.0/24	256
107.77.70.0/24	256
107.77.71.0/24	256
107.77.72.0/24	256
107.77.73.0/24	256
107.77.74.0/24	256
107.77.75.0/24	256
107.77.76.0/24	256
107.77.77.0/24	256
107.77.78.0/24	256
107.77.79.0/24	256
107.77.80.0/24	256
107.77.81.0/24	256
107.77.82.0/24	256
107.77.83.0/24	256
107.77.84.0/24	256
107.77.85.0/24	256
107.77.86.0/24	256
107.77.87.0/24	256
107.77.88.0/24	256
107.77.89.0/24	256
107.77.90.0/24	256
107.77.91.0/24	256
107.77.92.0/24	256
107.77.93.0/24	256
107.77.94.0/24	256
107.77.95.0/24	256
107.77.96.0/24	256
107.77.97.0/24	256
107.77.100.0/24	256
107.77.101.0/24	256
107.77.102.0/24	256
107.77.103.0/24	256
107.77.104.0/24	256
107.77.105.0/24	256
107.77.106.0/24	256
107.77.107.0/24	256
107.77.108.0/24	256

Showing the first 100 of 1,449, in address order. Complete list on RIPEstat

IPv6 prefixes (161 prefixes)

Prefix
2600:380::/37
2600:380:180::/41
2600:380:800::/37
2600:380:800::/38
2600:380:980::/41
2600:380:c00::/38
2600:380:1000::/37
2600:380:1180::/41
2600:380:1800::/38
2600:380:1800::/41
2600:380:1880::/41
2600:380:2000::/37
2600:380:2580::/41
2600:380:2800::/37
2600:380:3000::/37
2600:380:3180::/41
2600:380:3800::/37
2600:380:4000::/38
2600:380:4400::/38
2600:380:4500::/40
2600:380:4700::/41
2600:380:4800::/38
2600:380:4c00::/38
2600:380:4c00::/41
2600:380:4c80::/41
2600:380:4d00::/41
2600:380:4d80::/41
2600:380:5000::/38
2600:380:5300::/41
2600:380:5400::/38
2600:380:5800::/38
2600:380:5800::/41
2600:380:5880::/41
2600:380:5900::/41
2600:380:5980::/41
2600:380:5a00::/41
2600:380:5a80::/41
2600:380:5c00::/38
2600:380:6000::/38
2600:380:6000::/41
2600:380:6080::/41
2600:380:6100::/41
2600:380:6180::/41
2600:380:6200::/41
2600:380:6280::/41
2600:380:6300::/41
2600:380:6380::/41
2600:380:6400::/38
2600:380:6400::/41
2600:380:6480::/41
2600:380:6500::/41
2600:380:6580::/41
2600:380:6600::/41
2600:380:6680::/41
2600:380:6800::/41
2600:380:6900::/40
2600:380:6a00::/40
2600:380:6b00::/40
2600:380:6c00::/38
2600:380:7000::/38
2600:380:7400::/40
2600:380:7400::/41
2600:380:7500::/40
2600:380:7600::/40
2600:380:7600::/41
2600:380:7700::/40
2600:380:7700::/41
2600:380:7800::/40
2600:380:7800::/41
2600:380:7900::/40
2600:380:7900::/41
2600:380:7a00::/40
2600:380:7b00::/40
2600:380:7b00::/41
2600:380:7c00::/38
2600:380:7c00::/41
2600:380:7d00::/40
2600:380:7d00::/41
2600:380:8000::/40
2600:380:8400::/40
2600:380:8500::/40
2600:380:8600::/40
2600:380:8700::/40
2600:380:8800::/40
2600:380:8a00::/40
2600:380:8b00::/40
2600:380:8b00::/41
2600:380:8c00::/40
2600:380:8d00::/40
2600:380:8e00::/40
2600:380:9000::/40
2600:380:9100::/40
2600:380:9200::/40
2600:380:9400::/40
2600:380:9500::/40
2600:380:9800::/40
2600:380:9900::/40
2600:380:9a00::/40
2600:380:9b00::/40
2600:380:9c00::/40

Showing the first 100 of 161, in address order. Complete list on RIPEstat

Neighbours

Upstreams (transit or peers) (1)

AS	Network	Visibility
AS7018	AT&T Enterprises, LLC	1,040

Downstreams (customers) (1)

AS	Network	Visibility
AS64011	-	619

Visibility is RIPEstat's count of how often the route collectors observed the link. It compares neighbours with each other; it is not a traffic volume.

How to read this page

An Autonomous System (AS) is a network run under one routing policy: an internet provider, a cloud, a content network, a university. Each one has a number, its ASN, assigned by a regional registry (ARIN, RIPE NCC, APNIC, LACNIC, AFRINIC), and uses BGP, the protocol networks use to tell each other where addresses are, to announce the blocks of addresses it delivers to.

A prefix such as 203.0.113.0/24 is a block of addresses: the number after the slash says how many bits are fixed, so a /24 holds 256 IPv4 addresses and a /16 holds 65,536. Networks often announce a large block and smaller pieces of it at the same time, which is why the address total counts each address once.

Neighbours come from the paths themselves. A network that appears just before this one in a path, on the collector's side, is an upstream: a transit provider or a peer. One that appears just after it is a downstream, usually a customer. Peering at an internet exchange also shows up as an upstream, so the upstream list is not a list of paid transit.

The data comes from RIPEstat, run by the RIPE NCC, which gathers the routing tables of hundreds of networks through its RIS route collectors. This page reads it when it is visited and keeps it for 12 hours at most; the BGP viewer reads it live.

Frequently asked questions

How do I find the ASN of an IP address?

Type the address in the BGP viewer: it shows the prefix that covers it, the AS that originates that prefix and the paths seen towards it. A traceroute also names the network of each hop, so you can see every AS a connection crosses.

Why does one company have several ASNs?

Large operators split their network by region, by activity or by history: a cloud may use one number for its backbone and another for a region, and every acquisition brings its own numbers. Each number has its own page, with its own prefixes and neighbours.

Why do prefix counts differ from one site to another?

Each source sees the routing table from different collectors, at a different time, and counts differently: some include prefixes withdrawn in recent weeks, some merge a block and its pieces. This page counts the prefixes RIPE RIS collectors see originated by the network at the end of the latest two-week window, and counts each IPv4 address once.

Is this the list of IP ranges of a cloud provider?

It is what its networks announce, which is what the Internet routes to them. Many providers also publish an official list of ranges per service and region; that list is the reference for firewall rules, because a range can be announced before it is used, or announced by another of their AS numbers.