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RBL Advisories
Short for Realtime Blackhole List, is a company/ website that produces a list of IP addresses observed sending spam or other undesired email content.
As subscribers to the RBL, ISPs and companies will know from which IP addresses to block traffic. Most traffic blocking occurs during the SMTP connection phase. The receiving end will check the RBL for the connecting IP address. If the IP address matches one on the list, then the connection gets dropped before accepting any traffic from that email sender.
For a complete understanding of the blacklisting process and how it can affect your email delivery as well as your sender reputation, see our Understanding Email Blacklisting help doc.
The various RBL’s have different policies yet generally encompass the three major points:
- Goals. What does the RBL seek to list? Is it a list of open-relay mail servers or open proxies – or of IP addresses known to send spam – or perhaps of IP addresses belonging to ISPs that harbor spammers?
- Nomination. How does the RBL discover addresses to list? Does it use nominations submitted by users? Spam-trap addresses or honeypots?
- Listing lifetime. How long does a listing last? Are they automatically expired, or only removed manually? What can the operator of a listed host do to have it delisted?
Impressionwise maintains the largest most complete knowledgebase of known anti-spam, RBL or IP-based blacklists that can affect your online sending reputation and deliverability of your emails.
Highlights include detailed information for each site:
- Site name and description
- Threat-level
- Nomination process
- Listing lifetime
- Delisting guidance
Blacklist profiles
To view our knowledgebase of known anti-spam, RBL blacklist profile select from one of the following below.
For additional guidance or any questions you may have, please contact us.