Protecting e-mail addresses from spam

[Billiam]

I need advice on how to "protect" e-mail addresses from spam...I publish a
series of webpages in .pdf format (the links are not active as i am using
primopdf) which list an instructor's e-mail address. You need to first click
on a link to get to the .pdf pages...is this enough of a seperation to stop a
web harvesting of e-mail addresses?
Bill

 

[DavidF]

I hoped someone else might jump in and answer your question, but in my
opinion I doubt you have a problem. If you want to take it another step,
then perhaps go to:
http://members.tripod.com/semper.fi/oelc/index.htm
Obfusticated Email Link Creator
Or google the subject...

DavidF

 

[Billiam]

Thanks for your reply, David. I have hundreds of e-mail addresses to "
protect "...I was really hoping that since i had a click here link to take
you to the page where the e-mails are listed that they would be
safe...obvioulsy i am wrong??? The other process seems too lengthy... Is
there a general standard for protecting people's e-mail addresses that you
could fill me in on as we are adding this feature shortly, but I got to
wondering if i should be doing more to protect against spam etc.
Bill

 

[DavidF]

You misinterpreted my reply. I said I *didn't* think you had a problem...I
don't think the spambots crawl the pdf "image" for text...ie, for email
addresses. But you are asking a question that is best asked in an Adobe
newsgroup...ask there if a pdf file can be scanned for emails. I really
doubt it, but I could be wrong. Or Google it...

DavidF

 

[Billiam]

Hi David,

Sorry, David, I also meant to ask if the same situation applies to Publisher
2007 webpages...if the e-mail address has to be accessed by a button that
says 'e-mail" or contact the webmaster...is that usually enough of a
separation? From what I saw from google it appears that keywords such as
"e-mail" or "mailto" may be words to avoid if you can...
Bill

 

[Mike Koewler]

David,

I believe a pdf can be scanned for just about anything. I use Zoom
Search to create a search DB and it reads all text.

Now, how likely is a spambot going to scan pdf's? Not very. IMO, it
isn't worth their time as they rely on harvesting thousands of
addresses, knowing that only a very minuscule percentage (probably less
than 1 in 10,000) will reply.

FWIW, since I added a CAPTCHA to my forum, not a single spammer has
tried to join.

Speaking of which, an article I read the other day tested the
effectiveness of CAPTCHAs and the ability of a program to decipher them.
Surprisingly, one used on an MS MVP site was reported as fairly easy to
break, though it didn't look like it to me (it's based on levels on
noise, type of font(s), slant of characters, etc.)

Mike

 

[DavidF]

Read Mike's reply to this thread about being able to crawl a pdf file...

As to email links on a website, that is a different story. With my limited
knowledge of the subject, I believe it is the html code that is crawled by
the spambots, just like the search engines do to index the page. If the
email shows up in the html code it can be harvested. The link I gave you
gives you a way of munging up the email addresses in the html code.

As I said, with my limited knowledge, I am not the one to quote on this
stuff, but I have read that a form is the best way to limit the ability of a
spam harvester getting your email address. I personally have been useing the
following inserted as an email link on my sites:

(e-mail address removed)

instead of (e-mail address removed)

This supposedly is hard or not possible to harvest. I just copy and paste in
the hyperlink dialog. I can't say that it works or not...like I said, google
the subject for all the opinions on the subject.

DavidF

 

[DavidF]

Thanks Mike.

DavidF

David,

I believe a pdf can be scanned for just about anything. I use Zoom Search
to create a search DB and it reads all text.

Now, how likely is a spambot going to scan pdf's? Not very. IMO, it isn't
worth their time as they rely on harvesting thousands of addresses,
knowing that only a very minuscule percentage (probably less than 1 in
10,000) will reply.

FWIW, since I added a CAPTCHA to my forum, not a single spammer has tried
to join.

Speaking of which, an article I read the other day tested the
effectiveness of CAPTCHAs and the ability of a program to decipher them.
Surprisingly, one used on an MS MVP site was reported as fairly easy to
break, though it didn't look like it to me (it's based on levels on noise,
type of font(s), slant of characters, etc.)

Mike

 

[Billiam]

Thanks for the advice!
Bill

Thanks Mike.

DavidF

 

[Billiam]

Thanks Mike for the advice!

David,

I believe a pdf can be scanned for just about anything. I use Zoom
Search to create a search DB and it reads all text.

Now, how likely is a spambot going to scan pdf's? Not very. IMO, it
isn't worth their time as they rely on harvesting thousands of
addresses, knowing that only a very minuscule percentage (probably less
than 1 in 10,000) will reply.

FWIW, since I added a CAPTCHA to my forum, not a single spammer has
tried to join.

Speaking of which, an article I read the other day tested the
effectiveness of CAPTCHAs and the ability of a program to decipher them.
Surprisingly, one used on an MS MVP site was reported as fairly easy to
break, though it didn't look like it to me (it's based on levels on
noise, type of font(s), slant of characters, etc.)

Mike

 

[bjr]

You could also try this embedded coding technique:
http://www.wbwip.com/wbw/emailencoder.html