Power
93
•
Certain older Cisco Ethernet switches are capable of providing power over Ethernet cables
but are not fully IEEE 802.3af compliant. In this instance, a separate 3300 Power Dongle
(Cisco-compliant) can be used to allow the phone to be powered over the Ethernet cable
by the Cisco switch.
•
Cisco Discovery Protocol (CDP) is a protocol that allows Cisco switches to learn information
about devices on the LAN. CDP compliant LAN devices, such as IP phones, can advertise
their power requirements to the L2 switch and the L2 switch can then deliver the required
power to the connected device. This exchange of information via CDP is independent of
the 802.3af protocol.
RECOMMENDED PHONE POWERING
Power over Ethernet from a central location is recommended whenever possible, resulting in
the following benefits:
•
Reliable and redundant power backup (UPS), especially for emergency 911 operation.
•
Lower installation cost (existing cabling can be used).
•
International standard.
•
Remote reset and power-off capability.
Note:
The CXi and CXi II support the IEEE 802.3.af communication standard. Table 35
can be referenced to determine what the phones will advertise as their PoE power
requirements. The CXi uses IEEE 802.3af power advertisements sent from the phones
to determine what the power consumption will be, where as the CXi II actually measures
the current being drawn from the phones.
Note:
To ensure proper operation, avoid connecting the IP phone to both local and
remote power sources simultaneously. An IP phone that is locally powered, either
through an AC or an Ethernet power adapter, should have its remote power feed
disabled.
Содержание MiVOICE BUSINESS
Страница 1: ...Mitel MiVoice Business RELEASE 7 2 ENGINEERING GUIDELINES ...
Страница 15: ...Chapter 1 ABOUT THIS DOCUMENT ...
Страница 16: ......
Страница 22: ...Engineering Guidelines 8 ...
Страница 23: ...Chapter 2 SYSTEM OVERVIEW ...
Страница 24: ......
Страница 28: ...Engineering Guidelines 14 ...
Страница 29: ...Chapter 3 TYPICAL CONFIGURATIONS ...
Страница 30: ......
Страница 73: ...Chapter 4 PHONES AND VOICE APPLICATIONS ...
Страница 74: ......
Страница 95: ...Phones and Voice Applications 81 Figure 9 ICP Connection Paths and Limitations ...
Страница 100: ...Engineering Guidelines 86 ...
Страница 101: ...Chapter 5 POWER ...
Страница 102: ......
Страница 128: ...Engineering Guidelines 114 ...
Страница 129: ...Chapter 6 PERFORMANCE ...
Страница 130: ......
Страница 135: ...Chapter 7 APPLICATIONS ...
Страница 136: ......
Страница 142: ...Engineering Guidelines 128 ...
Страница 143: ...Chapter 8 EMERGENCY SERVICES ...
Страница 144: ......
Страница 151: ...Chapter 9 IP NETWORKING ...
Страница 152: ......
Страница 167: ...Chapter 10 LICENSING ...
Страница 168: ......
Страница 183: ...Chapter 11 BANDWIDTH CODECS AND COMPRESSION ...
Страница 184: ......
Страница 209: ...Chapter 12 NETWORK CONFIGURATION CONCEPTS ...
Страница 210: ......
Страница 244: ...Engineering Guidelines 230 ...
Страница 245: ...Chapter 13 NETWORK CONFIGURATION SPECIFICS ...
Страница 246: ......
Страница 309: ...Appendix A CAT 3 WIRING ...
Страница 310: ......
Страница 315: ...CAT 3 Wiring 301 Figure 55 CX MX MXe AX and LX Minimum Cable Standard ...
Страница 316: ...Engineering Guidelines 302 ...
Страница 317: ...Appendix B INSTALLATION EXAMPLES ...
Страница 318: ......
Страница 335: ...Appendix C LLDP AND LLDP MED CONFIGURATION EXAMPLES ...
Страница 336: ......
Страница 347: ...Appendix D VOIP AND VLANS ...
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Страница 353: ...Appendix E VOIP SECURITY ...
Страница 354: ......
Страница 381: ... ...