How Anchor Spam and Virus Protection Service works

There are a number of different methods available to block spam and viruses with different levels of effectiveness. To achieve the highest level of spam and virus protection whilst ensuring that an easy to use and reliable system is in place Anchor has adopted state of the art appliances from Barracuda to protect both web hosting and dedicated server customers.

The Barracuda is a hardware appliance that sits in front of our mail servers.

All incoming mail is routed through the appliance which passes each email through a number of layers:

Public IP blacklists are checked for known sources of spam
Rate controlling is used to detect spam floods and attacks
Two different virus signatures checks are performed
Spam finger prints are checked from online databases
Finally spam rule-based scoring and bayesian analysis is applied.

Any email that is detected to be a virus is automatically deleted.

By default, Spam is dealt with as follows:

Any email that is detected as being spam will be quarantined.
Quarantined email can be accessed via a web based interface
All email that is considered not be spam is sent to you as usual.

In a very small number of cases legitimate or real email will be mistakenly quarantined as spam. You can log into the quarantine area to retrieve these emails.

The Barracuda can be configured in many different ways, the default settings are a balance between ease of use and spam protection. We'll now go through all of the options you have available.

The service is customised on a per email address basis. To customise the service log into the quarantine area and choose the preferences tab.

Whitelist/Blacklist: You can build lists of email addresses that you never want to get email from (blacklist) or always want to get email from (whitelist). This is useful if the Barracuda isn't classifying email correctly.

Quarantine settings: You can change the frequency of the notifications about messages in your quarantine.

Spam settings: Here you can change how the Barracuda deals with spam. To modify the Spam scoring levels you need to first tell the Barracuda not to use the System defaults and click the 'save changes' button.

There are now three options you can change. Tag score, quarantine score and Block score.

The score system defines how aggressive the Barracuda is in detecting spam. Setting a higher score will increase the number of spams detected but also increases the number of real emails that are treated as spam. Setting a lower score will allow more spam through but also lower the chance of a real email being treated as spam.

For any email detected as being spam:

Tagging puts the word 'SPAM' at the start of the subject line and delivers it to your inbox.
Quarantine keeps the email in the quarantine area (website) and doesn't deliver it to you.
Blocking rejects the email and deletes it (this is not recoverable).

By default we:

Disable blocking to make sure you can't lose real emails.
Disable tagging because most users just don't want spam.
Set quarantine to 3.5.

Another approach to using the service is to disable the quarantine service and enable tagging. This works best if you setup filters in your email program that automatically but any email with a subject of SPAM into a separate folder.

Doing this means you'll never need to come near the website and you can review the automatic spam classification quickly and easily.