Network Guild Anti-Spam Service

Network Guild can filter mail for your domain removing a significant number of unwanted spam and nearly all viruses.

We have the ability to filter spam at several places:

1) we reject mail from certain well known spam sources

We use a series of "real-time block lists" to block mail from well known spam sources. These block lists are managed by a variety of different groups and companies, some free, others we pay for. There are over 200 such lists available on the internet, we have handpicked about 10 of the best, most accurate of these lists.

2) we reject mail from servers that do not follow the mail protocol

Most spammers do not use real mailers to send their spam. We can reject a large portion of spam just by being strict to the mail protocol and rejecting connections from mailers that do not follow strictly the mail exchange protocol. This includes using a popular method called "greylisting" which requires a mailer try to connect to
our server twice. Since spammers usually only try once, we can easily block such mail.

We also reject mail from servers which should not be sending mail on behalf of someone else. For example, mail from someone at microsoft.com should not come from a server at apple.com. We do this by checking something called an SPF record.

3) we scan all mail for viruses and automatically delete virus mail

We use the popular ClamAV anti-virus scanner to scan all mail and attachments. ClamAV also will reject "Phishing" mail, mail that is known to contain exploits to try to get your credit card or bank account passwords.

4) we further filter mail on the server

Once a message is received on the server, we can further run a series of tests on the message to determine if it is spam or not. We use a popular piece of software named Spamassassin. Spamassassin adds a flag to the mail if it thinks it's spam. This allows the user to create a filter in Outlook to dump the message directly into a spam-box.

We are constantly refining our filters to keep ahead of the onslaught of spam. As I write this, the amount of spam we see is more than 90% of all email. Our spam filters block approximatly 99% of the spam.

What we can do for your company:

We can act as a mail gateway for your mail for your domain. (see diagram above) All mail for your domain name will pass through our server and be treated by steps 1-3 above. You can (and should) firewall your server from the outside world and only allow it to talk to our server. In this case, your server is safe from direct attacks. Anyone sending you mail would contact our server and we will then pass on real mail to your server.

We can create individual mail boxes on your server and treat your mail with steps 1-3 and optionally 4 above.

Furthermore, with control of mail on our server, we have the ability using software named Procmail to do complex filtering on your mail. For example, we could create a filter to automatically forward all mail with a certain word in the header to a special mailbox for you. We also have the ability to create mailing lists for group
discussions, for example, if you needed a group to discuss automobiles, we could create an address like automobiles@yourdomain.com that was sent to all your friends who are interested in automobiles. Unlike a list of addresses in your address book, anyone on the list can send mail to the automobiles list and the mail comes to our server and is sent to all the readers.

We offer a free 30 day trial of our anti-spam service.

Lastly, if you have any special needs around mail, we can probably find you a solution. We specialize in creating specialized set ups for people with needs that go beyond what they can find at most off-the-shelf domain/web hosting services. So please don't hesitate to call us with your needs.