Glossary
Anti-Spam
Anti-spam tools prevent unwanted e-mail, which accounts for over 80 percent of e-mail on the Internet by some studies. Without anti-spam technology, organizations can face reduced bandwidth, waste of server resources, and higher infrastructure costs.
There are several deployment models for anti-spam tools. The Gateway model is primarily used by large corporations and involves the deployment of anti-spam technology at the edge of the network near the mail servers. Anti-spam gateways examine inbound mail before it reaches the organizational mail server and classify e-mail based on a number of parameters that generally include scans against a signature-based database as well as pattern matching.
Managed anti-spam services also examine inbound mail before it is delivered to the organizational mail server, but the service is external to the organization's network. This requires modifications to the organization's DNS records. The benefit of this model is that the enormous amount of spam delivered to an organization on a daily basis never consumes the network resources of the organization as the spam is discovered externally and never delivered to the organization. The potential pitfall of this model is that without strict service level agreements in place business processes that rely on e-mail may be compromised by delays.
The final deployment model for anti-spam tools is that of a desktop application. The application generally installs as a plug-in for popular e-mail clients like Outlook and allows the user to determine how mail identified as spam is treated. Many client-side anti-spam tools use the power of community to classify spam, allowing recipients to designate mail as spam and then share that information with a central site that then distributes the e-mail signature and header information to other clients.
The F5 BIG-IP® Message Security Module (MSM) extends security for message applications to the edge of the corporate network, eliminating unwanted e-mail. MSM is integrated into the application delivery control network and is based on the anti-spam gateway model. Mail is examined before it is delivered against a world-wide reputation-based database. If the mail is classified as spam, it is rejected and not delivered, saving the organization the cost of storing the spam to comply with regulations as well as reducing the overall consumption of network resources as the mail is delivered.