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services:e-mail_service:antispam_feedback [2011/03/28 17:42]
marina
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-====== Anti-Spam Feedback ====== 
- 
-To improve the spam filters we need a feedback by the users.\\ 
-  * **False positives** are legitimate e-mail messages that are mistakenly blocked or tagged as spam by the anti-spam filter .  
-  * On the other hand there are e-mails (**//false negatives//​**) that pass the anti-spam filters and arrives on the users' inbox, but they are spam. 
- 
----- 
- 
-Our internal anti-spam [[antispam_filters#​barracuda_spam_firewall|Barracuda Spam Firewall]] assigns to every incoming mail **a spam score value**. 
-E-mails with values higher than 3.5 are probably SPAM messages and the anti-spam tags their "//​subject line//" ​ with the identifier //**[Maybe SPAM]**// ​ 
- 
-**Only e-mails with very-very-high spam score (over 9 points) are blocked by the Barracuda Spam Firewall**. \\ 
-The others --//allowed or tagged as probably spam//-- are delivered to the final user. 
-\\ 
- 
- 
-  * See here about [[webmail-horde:​filter:​spam-level| how to manage my e-mail spam filters using HORDE ]]. 
-  * See here about [[webmail-squirrel:​filter:​spam-level| how to manage my e-mail spam filters using SQUIRRELMAIL ]]. 
-  * See at the end of this page about some useful answers to questions about spam. 
-\\ 
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-===== Anti-Spam Notifications ===== 
- 
-When you find a:\\ 
-  * **false positive** --mail tagged as SPAM or "​[Maybe-SPAM]"​-- which is NOT a real spam  
-or\\ 
-  * **a spam** mail without "​[Maybe-SPAM]"​ in the subject, 
-please forward it, with its complete header, to [[spam@sissa.it]] **specifying ​ in the //​subject//​** if it is: a **FALSE POSITIVE** or a **SPAM**. 
- 
-The operators take the notifications and update the filters. 
- 
-The COMPLETE headers are needed because they contain the information about the real sender and the e-mail delivery. ​ 
-We will take the notifications and update the filters, in order to make the filtering better. 
-\\ 
-You can find a [[services:​e-mail_service:​header-example|header example on the page: typical header]]. 
-\\ 
-You find below some instructions to correctly send us the complete header. 
- 
- 
-=== Using PINE to send us the complete e-mail header ==== 
- 
-You must enter/exit the //header mode// with the key **H**. ​ 
-When you enter the header mode, the program shows at the bottom of the screen an information message like: 
-  * //Display of full headers is now off// or 
-  * //Display of full headers is now on.// 
-Now you can forward us your e-mail. ​ 
-\\ 
- 
-=== Using Thunderbird to send us the complete e-mail header ==== 
- 
-Open the message and then select the menu **//​View//​** --> **//​Headers//​** --> **//​All//​**:​ you will see on the message window the complete headers of the messages. 
-Now you can forward us your e-mail. 
-\\ 
- 
-----  
- 
-===== Some Useful Answers to SPAM Questions ===== 
- 
-**What are false positives?​**\\ 
-False positives are legitimate e-mail messages that are mistakenly rejected or filtered by a spam filter. 
- 
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- 
-**Will I get false positive?​**\\ 
-Yes: for any false positives the sender will receive a bounce message 
-indicating the email did not go through. ​ 
-Your notification to [[spam@sissa.it]] of the false positive allows us to train the Bayesian filters and 
-further reduce the occurrence of false positives. 
- 
-\\ 
- 
-**What is Spam scoring, and the Bayesian Analysis?​**\\ 
-  * Spam scoring is the rules based system (about 4000 rules) that looks for characteristics in the email. The Spam scores are used to determine what to do with the email. They do not contribute directly to the future analysis. The rules are updated via the Updates Subscription that we maintain on Barracuda. 
-  * Bayesian analysis, also contributes to the Spam scoring. This is done using your notifications,​ so that we can flag some messages as either SPAM, or NOT SPAM in the message log. 
- 
-\\ 
- 
-**How Can I find out if an email that I am missing was blocked by Barracuda?​**\\ 
-You find in the INBOX_spam the e-mails stopped by Barracuda because of spam. You receive an e-mail notification concerning e-mails stopped because of viruses. 
-In case you have more questions you can contact the SIS helpdesk@sissa.it and we will check the message log for you. 
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