This list/zone contains (mostly) single ip's that have been blacklisted because of one of these reasons: IP is source of attacks against infrastructure or server - or - long term spam sending source. This list is intended to reject incoming smtp connections at smtp level and also to reject incoming tcp connections of any kind of service (for example apache webserver with activated rbl module).

• Zone-Name bl.shlink.org
• IP-based Blacklist
• Return-Code 127.0.0.2
• A-Records + TXT-Records

The TXT-Entry contains the date of blacklisting and the reverse dns name of the blacklisted ip-address.

This list/zone contains ip ranges mostly distributed to dsl, cabletv or wireless customers. This list may be used mainly for blocking direct smtp connections to mx-servers from enduser sites. Endusers with a dynamic allocated ip address never should send mail directly to an mx-server, they should always use their isp's mailserver for sending mail. This list is maintained manually and contains only a relatively small amount of netblocks compared with other similar zones (cdl.anti-spam.org.cn, dul.dnsbl.sorbs.net). Nevertheless this zone is effective as it contains most today spam-active dynamic ip-ranges and so will block a good amount of incoming smtp spam connections.

• Zone-Name dyn.shlink.org
• IP-based Blacklist
• Return-Code 127.0.0.3
• A-Records + TXT-Records

If you block smtp connections from dynamic ip ranges (you always will..) you may take a look to the rhsbl list below. This list primarily contains reverse domain names (rDNS) from ip-sources that never should send email to mx-servers. If your software is able to check rDNS names against a rhsbl you may combine these two lists for best results.

DMM means direct marketing mailer - these are companies that (mostly) are sending masses of newsletters. The reputation of these companies is extremely different. Most of them only send mail after the recipients have made any kind of so called double opt-in before. Some are known to not honour this, and some are anywhere in between. This list/zone is for informational use only, never use this list to block smtp connections on a public mx-server. If ever, one may use this to create private blacklists or for scoring within for example spamassassin.

• Zone-Name dmm.shlink.org
• IP-based Blacklist
• Return-Code 127.0.0.4
• A-Records + TXT-Records

This list/zone contains ip addresses that never should be blocked at smtp level. It contains both entries for government and some company mailservers (such that can be really trusted) and ip-addresses of some isp outgoing mailservers one should accept mail from always.This list/zone make sense in combined usage to reduce possible false positives of any kind of blacklist.

• Zone-Name wl.shlink.org
• IP-based Whitelist
• Return-Code 127.0.0.2 (trusted local entries)
• Return-Code 127.0.0.3 (trusted companies + government institutions)
• Return-Code 127.0.0.4 (isp mailserver)
• Return-Code 127.0.0.5 (other)
• A-Records + TXT-Records

While traditional remote ip blacklists (rbl) and whitelists (rwl) are well known, there is another type of black- and whitelist that is not ip-based but name-based. These lists/zones are called Right-Hand-Side black- or whitelists (RHSBL or RHSWL). It's called right-hand because it matches the right hand side of a senders mail address. For example, if in smtp dialog the sending server says MAIL FROM: spammer@spamdomain.xx the part right of the @-sign can be checked against a rhsbl (or rhswl). There is another useful usage - some software like spamdyke can do requests to a rhsbl even for matching the rdns name of the sender. This makes such rhsbl usefull as an addition to traditional ip-based blacklists (for example of senders with dynamic ip addresses).

This right-hand-side blacklist is name-based and contains mostly sender addresses and also rDNS hostnames mostly from hosts with a dynamically allocated ip-address. This list is for blocking connections at smtp-level.

• Zone-Name rhsbl.shlink.org
• Domain-based Blacklist (rDNS)
• Return-Code 127.0.0.2
• A-Records + TXT-Records

This list is effective to block smtp connections from dynamic ip-ranges that never should connect mx-servers directly and may be used together with the dyn.shlink.org list - see description there.

This right-hand-side name-based whitelist contains entries similar to the ip-based whitelist. This list/zone make sense in combined usage to reduce possible false positives of any kind of blacklist.

• Zone-Name rhswl.shlink.org
• Domain-based Whitelist (rDNS)
• Return-Code 127.0.0.2
• A-Records + TXT-Records