3Com Baseline 2226-PWR Plus User Manual

Also see for 3C16475BS: Datasheet

Contents

8 CHAPTER 1: I NTRODUCING THE B ASELINE SWITCHPower over Ethernet (PoE)The Switch supports Power over Ethernet (PoE) on all24 10/100 ports. If you plug in a compatible (IEEE802.3af compliant) device, the Switch will automati-cally detect and supply power to it.By default, PoE is enabled on all 24 ports. You canalso configure the PoE settings for each port from theWeb interface. For more information on configuringPoE, refer to “Configuring PoE” on page 40.SFP PortsThe two SFP ports support fiber Gigabit Ethernetshort-wave (SX) and long-wave (LX) SFP transceiversin any combination. This offers you the flexibility ofusing SFP transceivers to provide connectivitybetween the Switch and a 1000 Mbps core network.When an SFP port is in operation, the corresponding10/100/1000BASE-T port is disabled.Traffic PrioritizationThe Switch supports two types of traffic prioritization:■ Prioritization of IP phone traffic■ Priority QueuingPrioritization of IP Phone TrafficThe Switch can recognize when an NBX phone is con-nected to any of the ports 1 to 24. The Switch willautomatically detect the NBX phone when the phonestarts up, and will ensure that traffic to and from thephone is given the highest priority.To ensure that the NBX phone is recognized by theSwitch during its initialization, do not connect anydata source through the phone until the phone hasfinished its startup sequence.Once the phone is available for use, any data source(for example, a computer) can then be connected tothe phone’s pass-through port. This only applies ifyou use a single wall jack for your network connec-tion and use the pass-through LAN port on the NBXphone.Traffic Priority QueuingThe Switch also offers priority queuing. It examineseach packet that it receives to determine if it is prior-ity-encoded. If a packet is priority-encoded, theSwitch reads the priority level and determineswhether the packet should be directed through thenormal or high priority channel. This feature is useful,for example, during periods of excessive networkload, when one type of traffic may require priorityover another. The Switch is configured to complywith 802.1p, VLAN tagged frames.Traffic prioritization ensures that high priority data isforwarded through the Switch without being delayedby lower priority data. It differentiates traffic intoclasses and prioritizes those classes automatically.Traffic prioritization uses multiple traffic queues thatare present in the hardware of the Switch to ensurethat high priority traffic is forwarded on a differentqueue from lower priority traffic, and is given prefer-ence over that traffic. This ensures that time-sensitivetraffic gets the highest level of service.