Proxy authentication: allowlist or password

Username and password

Your client sends credentials with each connection. It works from anywhere, which suits laptops, containers and servers on changing addresses. The cost is a secret that has to be stored and kept out of code.

IP allowlist

You register the public addresses you will connect from, and the proxy accepts only those. Nothing secret travels with the request. It suits servers with a fixed address and is awkward when your own address changes. The ProxySeller dashboard has an IP allowlist page; check it for how it applies to each line.

A rule of thumb

Choose between them by where the client runs.

1. A server with a fixed address: use the allowlist.
2. A laptop, a CI runner or a container on shared infrastructure: use credentials.
3. Software that cannot send credentials, such as some browser setups: use the allowlist.

Mistakes to avoid

Do not paste credentials into a script that goes into version control. Do not allowlist an address you share with people you do not control. A 407 response means the proxy rejected your credentials or your address.