Depends on the level of security you wish to have. Hardware firewalls certainly cost more than software, but they have the added benefit of filtering and dealing with issues before they reach your server. They will also include private IP's and free up server resources. A software firewall will use your server resources and process issues on the server as it is received. Most dedicated providers will offer a shared hardware firewall as a cost effective alternative in comparison to a dedicated firewall.
Miguel Villegas, VP Sales & New Business Development CloudMega.net
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