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[802.3_4PPOE] late technical problem



Got this from George Zimmerman today:

I was looking at the connector current consequences for disconnecting for type 4 pses, and came across this statement:

145.2.8.7 Overload current 

If IPort-2P, the current supplied on a pairset by the PSE to the PI, exceeds ICUT-2P for longer than TCUT-2P, the PSE may remove power from that pairset. The cumulative duration of TCUT-2P is measured with a sliding window of at least 1 second width.

 

If Tcut-2P is between 50msec and 75msec (type 4 pses, table 145-16) what does it mean to say “The cumulative duration of TCUT-2P is measured with a sliding window of at least 1 second width.”  How do you measure a TIME with a sliding window of 1 second width?

 

After some email back and forth he suggests this as a fix:

145.2.8.7 Overload current 

If during any sliding window of one second width, IPort-2P, the current supplied on a pairset by the PSE to the PI, exceeds ICUT-2P for a cumulative duration of longer than TCUT-2P, the PSE may remove power from that pairset. The cumulative duration of TCUT-2P is measured with a sliding window of at least 1 second width.

 

 

Conversation on this? I will request that he files a late comment to fix this and I would like an agreed resolution such as not to add to the New Orleans workload.

 

 

Chad Jones

Tech Lead, Cisco Systems

Chair, IEEE P802.3bt 4PPoE Task Force