There are several levels to be aware of when making an allowlist: the Internet provider, paid and unpaid service providers, and the individual user.
Many Internetproviders allow you to make your own blocklists and allowlists. Note that entries into a blocklist often overwrite the allowlist. You’ll usually need an account to add and edit entries.
One well-known independent service provider is DNSWL.ORG, an anti-spam organization made up of volunteers that provides a publicly available, free (up to a certain point) allowlist. If you’re listed you’ll receive a detailed overview of the listed data, for example IP range and host names. Well-known paid providers include Spamhaus, Return Path, and Certified Senders Alliance (CSA). To get yourself listed with one of these providers, you’ll have to register with them and fulfill certain criteria. For example:
- Responsible and responsive approach to abuse from your own network
- Correct registration in Whois registry
- As yet no spam complaints about you
The providers check potential new entries using public and private sources. Here it will become relevant if a domain or IP address was already reported as spam. Networks with public users will receive a low rating for trustworthiness, whereas those with tight administrative control will receive a higher rating. Additional criteria ensure that an entry can later be removed from the allowlist. Criteria vary from provider to provider.
You can also create an allowlist on your computer with just a few clicks. More on that in the coming section.