Stamp notes that appliances are best suited to filtering email and Web traffic. When traffic loads are unknown or less predictable, however, he advises going with software on a server.
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If the server is overloaded, you can generally stick another CPU or additional memory in there, but you are a bit more constrained with an appliance, Stamp said. Appliances tend to be better when one can predict the load, and an organization generally knows how much email it gets in a day.
He also says that a general purpose security appliance might not be the best choice when the different types of traffic it filters are managed by different personnel in the organization.
If you have an organization where email filtering is supported by a different team than the web content, you have a lot of finger pointing when something goes wrong, he said. You need to determine ahead of time who owns the box and what procedures to follow for dealing with issues that arise.
Given those caveats, installing a security appliance still allows an organization to achieve a higher level of security without an excessive management headache. I currently feel we are fairly secure, because we attempt to be as proactive as possible, said Mueller. I realize that there is no such thing as perfection with security, but by being proactive, I believe we are handling and protecting the needs of our customers as well as our co-workers.