
Chapter 11
| Interface Commands
Power Savings
– 422 –
Command Usage
◆
IEEE 802.3 defines the Ethernet standard and subsequent power requirements
based on cable connections operating at 100 meters. Enabling power saving
mode can reduce power used for cable lengths of 60 meters or less, with more
significant reduction for cables of 20 meters or less, and continue to ensure
signal integrity.
◆
Power saving mode only applies to the Gigabit Ethernet ports using copper
media.
◆
Power savings can be enabled on Gigabit Ethernet RJ-45 ports.
◆
The power-saving methods provided by this switch include:
■
Power saving when there is no link partner:
Under normal operation, the switch continuously auto-negotiates to find a
link partner, keeping the MAC interface powered up even if no link
connection exists. When using power-savings mode, the switch checks for
energy on the circuit to determine if there is a link partner. If none is
detected, the switch automatically turns off the transmitter, and most of
the receive circuitry (entering Sleep Mode). In this mode, the low-power
energy-detection circuit continuously checks for energy on the cable. If
none is detected, the MAC interface is also powered down to save
additional energy. If energy is detected, the switch immediately turns on
both the transmitter and receiver functions, and powers up the MAC
interface.
■
Power saving when there is a link partner:
Traditional Ethernet connections typically operate with enough power to
support at least 100 meters of cable even though average network cable
length is shorter. When cable length is shorter, power consumption can be
reduced since signal attenuation is proportional to cable length. When
power-savings mode is enabled, the switch analyzes cable length to
determine whether or not it can reduce the signal amplitude used on a
particular link.
Note:
Power savings can only be implemented on Gigabit Ethernet ports using
twisted-pair cabling. Power-savings mode on a active link only works when
connection speed is 1 Gbps, and line length is less than 60 meters.
Example
Console(config)#interface ethernet 1/24
Console(config-if)#power-save
Console(config-if)#
Содержание ECS4120-28F
Страница 36: ...Contents 36...
Страница 38: ...Figures 38...
Страница 46: ...Section I Getting Started 46...
Страница 70: ...Chapter 1 Initial Switch Configuration Setting the System Clock 70...
Страница 86: ...Chapter 2 Using the Command Line Interface CLI Command Groups 86...
Страница 202: ...Chapter 5 SNMP Commands Additional Trap Commands 202...
Страница 210: ...Chapter 6 Remote Monitoring Commands 210...
Страница 216: ...Chapter 7 Flow Sampling Commands 216...
Страница 278: ...Chapter 8 Authentication Commands PPPoE Intermediate Agent 278...
Страница 360: ...Chapter 9 General Security Measures Port based Traffic Segmentation 360...
Страница 384: ...Chapter 10 Access Control Lists ACL Information 384...
Страница 424: ...Chapter 11 Interface Commands Power Savings 424...
Страница 446: ...Chapter 13 Power over Ethernet Commands 446...
Страница 456: ...Chapter 14 Port Mirroring Commands RSPAN Mirroring Commands 456...
Страница 488: ...Chapter 17 UniDirectional Link Detection Commands 488...
Страница 494: ...Chapter 18 Address Table Commands 494...
Страница 554: ...Chapter 20 ERPS Commands 554...
Страница 620: ...Chapter 22 Class of Service Commands Priority Commands Layer 3 and 4 620...
Страница 638: ...Chapter 23 Quality of Service Commands 638...
Страница 772: ...Chapter 25 LLDP Commands 772...
Страница 814: ...Chapter 26 CFM Commands Delay Measure Operations 814...
Страница 826: ...Chapter 27 OAM Commands 826 1 1 00 12 CF 6A 07 F6 000084 Enabled Disabled Enabled Disabled Console...
Страница 836: ...Chapter 28 Domain Name Service Commands 836...
Страница 848: ...Chapter 29 DHCP Commands DHCP Relay Option 82 848...
Страница 902: ...Section III Appendices 902...
Страница 916: ...Glossary 916...
Страница 926: ...CLI Commands 926...
Страница 937: ......
Страница 938: ...E092017 CS R02...