The policies can be defined to deny packets based on source and destination MAC addresses, IP addresses or TCP/UDP ports. Carrier Switches Metro Switch 3000 Series Resilient and Redundant Design A quick recovery and round-the-clock network is vital for service providers to establish a robust network. The Metro Switch 3000 Series provides comprehensive features to make sure network is well operated. The IEEE 802. 3ad Link Aggregation feature reduces network downtime by providing redundant paths and bandwidth aggregation to critical connections, while IEEE 802. 1w Rapid Spanning Tree Protocol (RSTP) and IEEE 802. 1s Multiple Spanning Tree Protocol (MSTP) allow immediate recovery from failed connections by sending packets via the backup link. Furthermore, since the Metro Switch 3000 Series supports backup power system, the power is supplied to the switch in case of an unexpected outage. Intelligent Fan Control Algorithm for Power Saving Fans play an important role in energy consumption since it's the key to heat dissipation. The Metro Switch 3000 features auto temperature detection and appropriate fan speeds with the Intelligent Fan Control algorithm based on complex mathematics and physics formulas. When the ambient temperature is low, the switch would decrease fan speed to prevent unnecessary power waste from excessive cooling. Removable Fan Modules (MGS-3712, MGS-3712F, MES3500-24F only) Removable fan modules provide flexibility and high availability, and they solve the noise problem when the modules are approaching the end of their life cycle. When necessary, customers can replace the fans with new ones by their own to save cost. Optimized Design for Metropolitan Area Network, MAN (MGS-3712, MGS-3712F, MES3500-24F only) The Metro Switch 3000 Series offers high operating temperature tolerance, flexible AC/DC dual-input power source as well as protection against humidity and dust for service providers to extend their networks...