|
|
This topic comprises 2 pages: 1 2
|
|
Author
|
Topic: What kind of spam is this???
|
|
|
Scott Jentsch
Phenomenal Film Handler
Posts: 1061
From: New Berlin, WI, USA
Registered: Apr 2003
|
posted 01-18-2007 03:24 PM
Thunderbird uses Bayesian filtering in addition to a white list to filter spam messages from its inbox. The whitelist allows all messages from anyone currently in your Address Book. The Bayesian filter trains itself to recognize the spam that you receive by also looking at the non-spam that you receive.
Bayesian filters are exactly what much of the spam these days is trying to circumvent by using embedded graphics, common words and phrases, and even text from weather sites.
By default, Outlook 2003 uses a profiling system that depends on regular updates from Microsoft to update the profiles used. If a message matches this profile, it gets acted upon.
Even though I use Outlook 2003, I don't use the built-in filter. Rather, I use a free add-on called SpamBayes, which is a Bayesian filter that scans incoming messages for spam as Outlook is retrieving them. It's quite effective.
It's very flexible in how it can be configured, as you can adjust its sensitivity and what it does when messages reach certain thresholds. For example, all messages that score 90 or more get tossed into a Junk E-Mail folder I never look at and auto-purge every two weeks (just in case someone says they sent me something and it got pitched by mistake). This folder currently has 4,504 messages in it, to give you an idea of how much spam I receive in two weeks.
I've never had a message land in the Junk E-Mail folder that didn't belong there. All messages which score more than 15 get moved into a "suspects" folder which I review and then tag as "Spam" or "Not Spam".
I used my existing spam-free E-Mail messages as training material for SpamBayes, so it has something to start with. If you have a folder of known spam, it will also use that to know what kind of spam you've been getting, too.
The nice thing about Bayesian filtering is that it applies to the messages that you receive. No corporate entity is being relied upon to come up with profiles, and with solutions that depend on a community of users submitting spam reports, you run the chance of people using the spam button for a delete button. I like being in control of things, even if it meant that it took a while to train, and I have to review some messages that are suspected spam.
SpamBayes will also show me what it's doing. I can see how many good messages it's using as a reference (775) and how many spam messages (21,454) as well. It will also display the clues for any message in my inbox, so that I can see why a particular message might have been tagged as spam (or not).
Long story short. You don't have to use Thunderbird to get Bayesian filtering. While it may be a great program, it's not for everyone. I haven't used Microsoft's built-in filter for 18 months, so I don't know how effective it now is.
All I know is that I'm very happy with the spam filtering I've got going on, even if I'm not happy with the fact that spam exists in the first place.
| IP: Logged
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Dave Macaulay
Film God
Posts: 2321
From: Toronto, Canada
Registered: Apr 2001
|
posted 01-26-2007 01:34 PM
"I would have thought the act of downloading the message would do more harm than just reading it. What if you are not connected to the Internet when you open the message?"
Downloading doesn't cause any problem. The way the internet works, unless your computer or your ISP sends a return email type message to the sender there is no way for the sender to know what happened to the message.
If you send an email to a nonexistent address you'll usually get a return mail telling you you've screwed up; that doesn't work too well for spammers because most spam uses false "from" and "return to" addresses so even if you send a "no such address" message the sender (real sender) won't get it.
Even if you download an email with a dangerous virus attached, you won't be infected until you open the message or attachment. This is why Outlook's preview pane is dangerous: if you start at the top of your mail list and delete the top item, the next one is highlighted and opens in the preview pane. The top item in the list will always open by default. The preview panes can be disabled.
Next problem is HTML/RTF email formats. Outlook can not be convinced to ignore this encoding, it will always open and display an HTML/RTF email as a formatted image. That's a choice MS made long ago and is obviously unwilling to change.
Most add-on email clients allow you to open messages as text only, this eliminates the "pixel bug" or image download that says "yay this is a valid email I can sell now!" sent to your spammer.
Pixel bugs are just oddly named very small image tags embedded in an HTML page. The name of the image identifies YOU. Your computer sends a GET message to the spammer's server asking for the image file, his server notes the image name (and tags your email address as good) and sends you a default image. This will also work with any image in an HTML page/message but that's a bit harder to keep track of at the server end so people get the correct images.
Disconnecting from the internet does make HTML pixel bugs fail. It's just a pain to bother with and sometimes impractical. Better to just never open suspect/unknown messages. Seriously, the viagra is fake, the hot babes don't exist, messages with bayesian evading nonsense subjects are pretty easy to avoid, and the stock being pumped will go down like the Titanic.
| IP: Logged
|
|
|
|
Scott Jentsch
Phenomenal Film Handler
Posts: 1061
From: New Berlin, WI, USA
Registered: Apr 2003
|
posted 01-30-2007 05:14 PM
quote: Dave Macaulay
The biggest problem with outlook & outlook express is the preview pane in email folder listing. This opens the email when you highlight it, any "virus" is immediately activated (actually this is a fairly unusual event) but the biggest problem is that HTML email will open the images or whatever from the remote site and in doing so tell the spammers that your email address is valid.
Outlook 2003 does not view remote images by default, you have to enable that feature globally or on a "by sender" basis. (You can mark certain senders as "safe.")
Outlook 2003 also blocks links in HTML E-Mails by default, and you can set all messages to be viewed in a restricted zone so that Javascript and other garbage is not automatically run. I believe this behavior is by default and would have to be overridden on purpose. I cannot speak for previous versions of Outlook or for Outlook Express, as I've never used them.
quote: Wayne Keyser
About "whitelisting" - so how do you ever get email from someone not on your already-permitted list?
This must leave you open to a certain amount of "sorry, Dr. Jones, I forgot to whitelist you so I didn't see your email telling me I had seven days to live that you sent - uh, let me see - 6 days ago."
Okay, I'm using humor, but don't you miss some communications you wish you hadn't?
My spam solution doesn't use whitelists. My mention of them was in the context of how Thunderbird uses whitelists to identify good messages. The whitelists aren't used to block messages from people that aren't on the list (as far as I can tell from their web site), but rather to allow all messages that do come from someone on the whitelist.
Blocking exclusively by using a whitelist is too restrictive, and I would never use that method except in very specific situations. I get messages from people's whitelist blockers that want me to go to some web site and answer a question in order to get unblocked. I don't have the time to chase white rabbits, so I just leave the challenge unanswered.
To answer your question, I've never known of an E-Mail that was mistakenly sent to my Spam folder that should not have been. That's from over three and a half years of receiving E-Mail, which amounts to hundreds of thousands of messages.
Some good messages do land in my "Spam Suspects" folder, but that's what that folder is there for. It gives the Bayesian filter a chance to learn by telling it whether a questionable E-Mail is spam or not. It's quite effective, and one of the first questions I posed to the Microsoft presenter at today's launch of Office 2007. Unfortunately, they didn't know whether the built-in spam filter was now using Bayesian filtering in addition to profile-based filtering.
| IP: Logged
|
|
|
|
All times are Central (GMT -6:00)
|
This topic comprises 2 pages: 1 2
|
Powered by Infopop Corporation
UBB.classicTM
6.3.1.2
The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion
and agrees to release the authors from any and all liability.
|
Home
Printer-friendly view of this topic