The Switch Chassis features include – chassis dimensions, number of slots, processor slot assignments, switching fabric, engines types supported, power supplies, rack units needed.A necessary starting point in the discussion is agreeing that a VoIP should provide better performance and reliability than the traditional PBX that it replaces, and doing that means not cutting corners.
When there is a problem with power in the building, a traditional PBX will continue to power the phones for at least a few minutes, and more if there is a good size UPS connected to the PBX in the phone room. The VoIP phone system should have that same capability, which means that IP phones should not be powered by plugging them into wall power.You can find all kinds of poe switch 8 port by visting online websites.
If the device plugged into the Ethernet cable is compatible, the device will function properly. In order to insure compatibility, standards have been established. The most widely used standards are IEEE 802.3af-2003 and IEEE802.3af-2007. The standard power provided is 15.4 watts. For a larger network with multiple devices, Ethernet midspans are available with 4, 8, or more ports. There are also PoE injectors that provide higher power. These high power units can provide up to 25 to 60 Watts of power.