The SonicWALL SonicOS 2.0e for the SonicWALL TZ 170 series extends the feature set on the firewall to include support for the following features: WAN ISP Fail-Over and Load Balancing: The SonicWALL TZ 170 offers the ability to configure the Optional port as a secondary WAN port, delivering highly reliable network connectivity and robust performance. This secondary WAN port can be used in “active-active” load sharing or fail-over configuration providing a highly efficient method for maximizing total network bandwidth.