Spam_BLIP

Spam BLIP stops comment and ping spam from being posted, primarily by

checking the IP address attempting to post a comment in one or more

of the public DNS blacklists. A number of options are available

to refine the check, and with the option defaults, a DNS lookup

is only performed the first time an address attempts to post a

comment; thereafter, the address might quickly ‘pass’ because it

was not listed, or quickly be rejected because it was listed.

Spam BLIP creates, and maintains, a database table for this purpose,

and database lookups are quite fast. Therefore, concerns about

DNS lookup time can be limited to an initial comment attempt.

Here are some features of Spam BLIP to consider if you are

not yet falling over yourself to get it installed:

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When WordPress is producing a page for a visitor, it checks

whether comments are open for each post, and it allows plugins

to “filter” the check. Spam BLIP uses that filter, but does not

do DNS lookups at this stage, because DNS lookups can take

perceptible time. Spam BLIP does check optional user-set

black and white lists, and optionally existing comments that

are marked as spam, and of course Spam BLIP’s own database records.

Those checks are fast, so they should not have a perceptible

effect on page loading. Furthermore, on pages with multiple

posts, WordPress runs the filter for each, but Spam BLIP

stores the first result, so even the fast checks are not

repeated.

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When a comment is actually submitted, Spam BLIP does the above

checks, then the DNS lookup only if necessary. At this stage,

if the DNS lookup causes a perceptible delay, a real human

(or very clever pet) making the comment should perceive it

as mere server-side processing. As for spammer robots...

let them wait.

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Spam BLIP comes configured with blacklist domains that have

worked well during development, so a user should not need to

be concerned with the blacklists, but there is an advanced

option to add or delete, activate or disable (yet save)

list domains, and configure the interpretation of a return

from a successful lookup.

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Spam BLIP provides user-set whitelist and blacklist options.

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Spam BLIP provides options to check for pings/trackbacks, and

for user registrations. (The option to blacklist-check user

registration is off by default. See “Tips” under the help

)

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Spam BLIP provides options to configure a ‘Time To Live’ (TTL)

for its database records, and a maximum number of records.

The TTL is important because, generally, an IP address should

not be marked permanently. Consider an ISP that quickly

disables any account that is found to be spamming. An honest

ISP is also a victim of spammer abuse, and will need to reuse

addresses. DNS blacklist operators provide means for IP

address owners to get records removed — Spam BLIP provides

a configurable TTL for its records. (Database table maintenance

)

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Spam BLIP will optionally check if a commenter address is a

TOR exit node. TOR (The Onion Router) is an important protection

for people who need or wish for anonymity. You may want to

accept comments from TOR users (you should), but unfortunately

spammers have exploited and abused TOR, which has led some

DNS blacklist operators to include TOR exit node addresses

whether or not it is known that the address is spamming. If you

enable this option (you should), it might let some spam get

through. In this case, mark the comment as spam, and use the

Spam BLIP option to check existing comments marked as spam; or

use Spam BLIP in concert with another sort of spam filter, such

as one that analyzes comment content. (Please report any

conflict with other, non-DNS blacklist type spam plugins.

Note that Spam BLIP is not expected to work in concert with

)

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Spam BLIP includes a widget that will show options and records

information. The widget might or might not be an enhancement

to your page, but in any case it should provide feedback

while you evaluate Spam BLIP, so it might be used temporarily.