Black Box LPB2910A User Manual page 307

3-­‐11.4EEE
By using EEE power savings can be achieved at the expense of traffic latency. This latency occurs due
to that the circuits EEE turn off to save power, need time to boot up before sending traffic over the
link. T his t ime i s c alled " wakeup t ime". T o a chieve m inimal l atency, d evices c an u se L LDP t o e xchange
information about their respective tx and rx "wakeup time ", as a way to agree upon the minimum
wakeup t ime t hey n eed.
This p age p rovides a n o verview o f E EE i nformation e xchanged b y L LDP.
Web I nterface
To s how L LDP E EE n eighbors:
4. Click M onitor, L LDP, t hen c lick E EE t o s how d iscovered E EE d evices.
5. Click R efresh t o m anually u pdate t he w eb s creen.
6. Click A uto-­‐refresh t o a uto-­‐update t he w eb s creen.
Figure 3 -­‐11.4: The L LDP N eighbors E EE i nformation
Parameter d escription:
Local P ort:

The p ort o n w hich L LDP f rames a re r eceived o r t ransmitted.
 Tx T w:
The l ink p artner's m aximum t ime t hat t he t ransmit p ath c an h old o ff s ending d ata a fter r eassertion
of L PI.
Rx T w:

The l ink p artner's t ime t hat t he r eceiver w ould l ike t he t ransmitter t o h oldoff t o a llow t ime f or t he
receiver t o w ake f rom s leep.
Fallback R eceive T w:

The l ink p artner's f allback r eceive T w.
A receiving link partner may inform the transmitter of an alternate desired Tw_sys_tx. Since a
receiving l ink p artner i s l ikely t o h ave d iscrete l evels f or s avings, t his p rovides t he t ransmitter w ith
additional information that it may use for a more efficient allocation. Systems that do not
implement t his o ption d efault t he v alue t o b e t he s ame a s t hat o f t he R eceive T w_sys_tx.
Echo T x T w:

The l ink p artner's E cho T x T w v alue.
The respective echo values shall be defined as the local link partners reflection (echo) of the
remote link partners respective values. When a local link partner receives its echoed values from
the remote link partner it can determine whether or not the remote link partner has received,
registered and processed its most recent values. For example, if the local link partner receives
echoed parameters that do not match the values in its local MIB, then the local link partner infers
N : If your network does not have any devices that have the EEE
OTE
function enabled, then the table will show "No LLDP EEE information
found".
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Publication date: Sept, 2015
Revision A1