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[802.3_10SPE] number of nodes for the multidrop channel

Dear all,


I have a comment/question concerning the 15 participants in the multidrop channel.


In the measurements of the multidrop channel we presented, we had 8 participants. In this set up a change of the MC to 43dB (which in our opinion would be an important change) is (just) feasible. Who is going to present measurements of the channel in Geneva that show, whether 15 participants yield the same results? What is the motivation behind 15 participants? Is there a specific application for which 15 units on 25m is necessary?


In my understanding, it is always allowed to use the multidrop link with more than the specified number of units (technical feasibility might be possible e.g. because you have a significantly shorter link). However, if 15 is defined for 25m, then it needs to work, even if in 99.9% of the cases it is either 15 units or 25m but not both at the same time.


Of course delays increase with the number of nodes. However, this is also a job for the network designer to decide on acceptability.


Any comment?


Kind regards,




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