Greylisting is a new weapon to use against spam in this great war being waged upon it. With this new shielding method, by which you may block out huge amounts of spam, you are sure to please your email clients!

In name, as well as operation, greylisting is related to whitelisting and blacklisting. What happen is that each time a given mailbox receives an email from an unknown contact (ip), that mail is rejected with a "try again later"-message (This happens at the SMTP layer and is transparent to the end user).

This, in the short run, means that all mail gets delayed at least until the sender tries again - but this is where spam loses out! Most spam is not sent out using RFC compliant MTAs; the spamming software will not try again later.

Legitimate email servers are all RFC compliant and legitimate email will be dealyed typically by 5-10 minutes and correctly delivered.

Libra Esva uses a multilayer anti-spam engine,which allows it to block 99.97% of spam - Virus Bulletin Spam test July 2010 - with only 0.12% False Positive rate!
These incredible results are achieved by applying  13 successive levels of analysis to every incoming message before being delivered to the final recipient, as illustrated below:

SPF (Sender Policy Framework) is a mechanism used to reduce email forgery, allowing you to declare where on the internet your domain sends email from.

Libra Esva supports it as integrated check in it's multi-layered antispam engine.

The general idea is that a recipient email server can check your SPF records and if the sending email server is listed in these records the email will be accepted. If the sending server is not in the list then the email can be further actioned upon, such as rejected or held in quarantine.

One of the benefits of declaring an SPF record is the reduction of backscatter spam.

It is important that email administrators manage SPF correctly if they are using it. If a sending email server is being moved to a new hostname or IP address which hasn't been declared in the SPF records, then any recipient email servers which use SPF as part of their mail filtering may block emails coming from the domain and sent from the new server unless they are whitelisted.

Additionally, if users change the outbound server setting (for example to their ISP's outbound email server) on their email applications and their domain uses SPF, they may not be allowed to send to other users whose mail server checks SPF records as part of their filtering.

The SPF records for a domain are defined in the domain's DNS records.

Further information on setting up SPF records for your domain can be found here: http://old.openspf.org/wizard.html

General SPF information: http://www.openspf.org

Lecco, 06 Novembre 2010

Libra Esva version 2.0.5.0 has been released!

This versione includes a new engine for message content analisys!

Other new functionalities:

• New graphical login
• New diagnostics functions in console menu for user admin
• Message Content Protection (MCP) engine
• New SMTP AUTH user creation
• New Active Directory user import
• Better handling of some maitenance scripts
• Additional mid-day schedule for Quarantine Digest Report
• Minor Fixes

Version 2.0.5 it's available as upgrade file from previous version or as full appliance.

Lecco, September 9, 2010

Libra Esva version 2.0.4.1 released!

This version includes :

• New Quarantine Digest Report with Release and Learn and Release & Whitelist shortcuts without user authentication
• New function to switch greylisting on and off
• Exchange plugin now has the possibility to overwrite/merge active user list
• Disabled double extension filename restriction (i.e.: document.doc.pdf)
• Active Directory Authentication subtree search and error handling fixes
• Some cosmetichs changes on hme page with different icons for each message type.

Available as upgrade script from version 2.0.4.0. See download section.

Lecco, July, 14th

Libra Esva version 2.0.4.0 released!

This version includes many important new product functionalities:

- New Microsoft Active Directory Domain Authtentication support!
- New Whitelist/Blacklist text file import function!
- New setting to set incoming Max Message Size
- New System Message Report customization for both user messages and email footers
- New Maillog Viewer
- New Filename & FileType Checking Exclusion for a single mailbox that will be able to receive any attachement sent.

Moreover minor fixes and tunes.

This is one of the most corpous update for new fuctionalities since Libra Esva initial release. It's available as upgrade file from previous version or as full appliance.

Lecco, June 7 2010

Libra Esva version 2.0.3.2 has been released with important new features!

This version includes a completely new graph engine used in reports, and the possibility to export them in PDF format!