OS10 Enterprise Edition User Guide Release


Energy-efficient Ethernet

Energy-efficient Ethernet (EEE) reduces power the consumption of physical layer devices (PHYs) during idle periods. EEE allows Dell Networking devices to conform to green computing standards.

An Ethernet link consumes power when a link is idle. EEE allows for Ethernet links to use the regular power mode only during data transmission. EEE is enabled on devices that support LOW POWER IDLE (LPI) mode. Such devices can save power by entering LPI mode during periods when no data is transmitted.

In LPI mode, systems on both ends of the link saves power by shutting down certain services. EEE transitions into and out of LPI mode transparently to upper-layer protocols and applications.

EEE advertises during the auto-negotiation stage. Auto-negotiation detects abilities supported by the device at the other end of the link, determines common abilities, and configures joint operation.

Auto-negotiation performs at power-up, on command from the LAN controller, on detection of a PHY error, or following Ethernet cable re-connection. During the link establishment process, both link partners indicate their EEE capabilities. If EEE is supported by both link partners for the negotiated PHY type, the EEE function is used independently in either direction.

Changing the EEE configuration resets the interface because the device restarts Layer 1 auto-negotiation. You may want to enable Link Layer Discovery Protocol (LLDP) for devices that require longer wake-up times before they are able to accept data on their receive paths. Doing so enables the device to negotiate for extended system wake-up times from the transmitting link partner.

Rate this content

Easy to understand
Was this article helpful?
0/3000 characters
  Please provide ratings (1-5 stars).
  Please provide ratings (1-5 stars).
  Please provide ratings (1-5 stars).
  Please select whether the article was helpful or not.
  Comments cannot contain these special characters: <>()\