ASN targeting proxies: how ISP targeting works

What is an ASN, in plain terms?

The internet is a network of networks. Each one that routes its own addresses, from Comcast to a city-owned fiber utility, gets an autonomous system number from a registry such as ARIN, and uses BGP to tell other networks which IP ranges (prefixes) it can reach. That announcement is public. Tools such as RIPEstat read it from route collectors around the world, so anyone can look up which ASN announces a given IP.

For a home IP, the ASN is almost always the customer's internet provider. That is why ASN targeting is the practical way to say 'give me a Comcast home' or 'give me a Verizon Fios home'.

Why does one ISP have several ASNs?

Mostly because of acquisitions. When a cable company buys another, it often keeps the old network running under its old number for years. Charter's Spectrum is the clearest case: RIPEstat lists AS20115 for Charter, but also AS10796, AS11427, AS12271 and AS20001 for former Time Warner Cable regions and AS33363 for former Bright House Networks, each still announcing millions of addresses (checked 2026-10-18). Comcast holds AS7922 plus regional numbers such as AS7015 and AS7725.

Telcos are usually simpler. AT&T's consumer network is AS7018, Verizon Fios is AS701 and Frontier is AS5650. Each ISP page lists the numbers we found and which one to try first.

Can I trust the name of an ASN?

Not always. Registered names are old and rarely updated. AS701, which carries Verizon Fios homes, is named 'UUNET - Verizon Business'. Mediacom's residential ranges are announced by an ASN named 'MEDIACOM-ENTERPRISE-BUSINESS', while its 'MEDIACOM-RESIDENTIAL-CUST' ASN announced nothing on 2026-10-18. Ziply Fiber routes on an ASN registered as 'Wholesail networks'. Judge an ASN by what it announces and where, not by its label.

How does the gateway pick an IP for my ASN?

The pool is made of home devices whose owners opted in through partner networks (sourcing). For each request, the gateway looks for a device that matches every filter in your username: country, then state, city and ZIP if given, then ASN. If several match, you get one of them; in rotating mode, a new connection usually gets a different one. Each new connection gets an IP from the pool, usually a different one; to get a new IP on every request, send one request per connection (turn off keep-alive).

If no device matches at that moment, the request can fail. Do not assume a result came from the network you asked for: log the exit IP and check its ASN, as in check the ASN of your exit IP. When requests fail, drop the narrowest filter (ZIP, then city) and retry.

What happens after a merger?

Ownership changes overnight; routing changes slowly. Cox joined Charter effective August 19, 2026, but Cox homes still route on AS22773. AT&T bought Quantum Fiber on February 2, 2026, yet many of those homes still sit on Lumen's AS209. Target the ASN that announces the IPs today, and recheck after big deals. The mergers guide covers every 2025–2026 deal that matters.

Is a home IP on an ISP's ASN the same as an 'ISP proxy'?

No. Sellers use 'ISP proxy' for static IPs that an ISP registered but that sit in a data center. Those IPs belong to the ISP's ASN too, but no household uses them. Residential proxies targeted by ASN are real home connections on that network. The difference matters when a site looks at more than the ASN. See ISP proxies vs residential by ISP.