ZyXEL Communications XGS2220 Series, Руководство пользователя

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Chapter 1 Getting to Know Your Switch
XGS2220 Series User’s Guide
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1.2 Example Applications
This section shows a few examples of using the Switch in various network environments. Note that the
Switch in the figure is just an example Switch and not your actual Switch.
1.2.1 PoE Example Application
The following example figure shows a Switch supplying PoE (Power over Ethernet) to Powered Devices
(PDs) such as an IP camera, a wireless router, an IP telephone and a general outdoor router that are not
within reach of a power outlet.
Figure 4 PoE Example Application
Table 5 PoE Standards
PoE FEATURES PoE PoE+ PoE++
IEEE Standard IEEE 802.3af IEEE 802.3at IEEE 802.3bt
PoE Type Type 1 Type 2 Type 3
Switch Port Power
Maximum Power Per Port 15.4 W 30 W 60 W
Port Voltage Range 44 – 57 V 50 – 57 V 50 – 57 V
Cables
Twisted Pairs Used 2-pair 2-pair 4-pair
Supported Cables Cat3 or better Cat5 or better Cat5 or better