[8023-POEP] IEEE 802.3at task force input required from 100BASE-TX PHY Vendors

["Fred Schindler (frs)" <frs@xxxxxxxxx>]

Hello,

 

The IEEE 802.3at, PoE plus, task force would appreciate answers from 100BASE-TX PHY vendors to the following questions before Wednesday April 16.  Later submissions will still be accepted.

1)       When was baseline wander correction added your shipping 100BASE-TX PHYs?

2)       What was the main reason for this introduction?

3)       At what interface is the correction performed (TX, RX, or both)?  Why?

4)       What is your and the industry approximate accumulative port volume of 100BASE-TX before and after the baseline wander correction was introduced?
This can be expressed as percent of total ports shipped before and after the baseline wander introduction.

5)       Please quantify the benefit baseline wander correction provides in terms of Ethernet transformer bias current.  A 100BASE-TX operation requires a 350 uH transmit (TX) transformer inductance with 0 to 8 mA bias current present.

6)       How often does a 100 MBPS killer-packet occur for a generic Ethernet network?

7)       If a killer-packet occured for a failed data transmission, how probable is a killer-packet when the same data is retransmitted?

8)       Do you anticipate efforts in IEEE 802.3az (EEE) or IEEE 802.3ba (HSSG) to result in changes that will affect baseline wander correction or 100BASE-TX?  Please explain.

 

These answers provided will help determine the current unbalance requirements for IEEE 802.3at.  The latest related presentation for these efforts is available at:

http://grouper.ieee.org/groups/802/3/at/public/mar08/schindler_2_0308.pdf

 

Thanks,

 

Fred Schindler

Technical Leader

CISCO Systems

170 West Tasman Drive

M/S SJ-19-3

San Jose, CA 95134-1706

Tel. (408) 525-9859