Barracuda Spam Firewall
The Barracuda Spam Firewall is compatible with all email servers and can fit into nearly any corporate or small business environment. It is used by small organizations with as few as 10 employees and large organizations with as many as 200,000 employees. A single Barracuda Spam Firewall handles up to 25,000 active email users and 15 million email messages per day. The Barracuda Spam Firewall protects your email server with ten defense layers:

  Denial of service and security protection
  IP block list
  Rate control
  Virus check with archive decompression
  Barracuda virus check
  User-specified rules
  Spam fingerprint check
  Intention analysis
  Bayesian analysis
  Rule-based scoring

• Email content checking/filtering.  Mail essentials can check all inbound and outbound mail for objectionable content.  Mail essentials can check for:
• Dangerous attachments, such as .exe and .vbs.  As these file types are likely to carry viruses or worms, it is best to quarantine them immediately before they get distributed to your users.  An administrator can review quarantined mail for further action, either approval or rejection.
• Script code within the body of the message itself.
• Offensive content or confidential content (by keyword).
• Other attachments as you see fit, such as .mp3 or .mpg, which are space and bandwidth hogs.
• Automatic removal of HTML scripts.  HTML mail is a real danger to your network.  It is possible for unscrupulous people to embed command in HTML mail that can cause damage your network clients.  Mail essentials can detect and remove these commands before the mail makes it into the network.
• Automatic quarantining of Microsoft Word documents with macros.  Any Microsoft Word or Excel documents that cross into your network via incoming email will be scanned for macros.  If macros are found the message will be quarantined, awaiting administrative action.  This serves to protect you against all current and future macro viruses.
• Virus checking.  Mail essentials features the enterprise level Norman anti-virus engine as an integral part of its system.  All messages coming to our leaving your network can have their attachments scanned for viruses, preventing the spread of viruses on your network and saving you the embarrassment of dealing with infections caused by your outgoing messages.  The virus definition files can even be automatically updated by Mail essentials, further increasing your level of safety and protection.
• Rule-based configuration.  You can configure multiple content checking and file checking rules, which allow you complete control and flexibility in how you check message traffic coming into and going out of your network.
• Control quarantined mail.  If you wind up with quarantined mail (and you will), you have two ways in which to deal with.  You can work with quarantined mail via an e-mail client, typically done by the administrator, or by using the Moderator Client.  Using the Moderator Client allows you to delegate this responsibility to other administrative personnel.
• Detects attachment extension hiding.  Email attachments with scripts (for example *.vbs) can be disguised as *.txt files by using the CLSID of the extension instead of the actual file extension. Mail essentials detects this and quarantines script or executable files, even if they are disguised as *.txt files, for example.
• Anti-spam.  Mail essentials uses a fairly smart anti-spam scanner to detect typical spam practices, such as incorrect Reply To addresses, From headers with incorrect domains, etc.  Because spam is stopped at the door, you save time and money.
• Personalized server-based auto replies with tracking number.  When running on Windows 2000, Mail essentials can give more than just a standard “out of the office” reply.  Automatic replies can be assigned tracking numbers and contain custom text, letting your outside contacts know that their message was received and is traceable.
• POP3 downloader.  Mail essentials can download, forward and distribute mail retrieved from Internet POP3 mailboxes to your Exchange Server mailboxes—something Exchange simply can’t do on its own.
• Reporting.  You have the ability to create reports on just about all facets of Mail essentials operation, including:  daily statistics, detailed log of sent mail, reports per user, etc.  These can be used for costing or tracking as you see fit.
• Automatic disclaimer text.  Because companies are seen as being responsible for the mail that employees generate, it can serve to protect the company by placing a disclaimer on all outgoing mail.  Additionally, you can place a standard footer on all outgoing mail, such as a slogan, location or public key. 
• Mail archiving to a database.  Although this will be viewed as a bad thing by some, Mail essentials allows you to archive all incoming and outgoing messages in an ODBC database of your choosing. This can use to create an additional backup of the messages, for quality control or legal purposes.