[Soekris] Strange problem with net4801

Chris Cappuccio chris at nmedia.net
Thu Jan 20 17:41:25 UTC 2005

Horst Laschinsky [horst.laschinsky at physik.uni-erlangen.de] wrote:
> Well OK. Now I understand the fact that shielding on both ends
> sometimes _causes_ line noise instead of avoiding it. OK, thats
> pretty clear now. But... :-)

Talk to anyone in telco and they'll tell you that you can easily have the
same problems (if you ground both ends) with shielded E1 cable bundles, DSL
bundles, etc, the difference in ground potential between devics is a big deal

> 1.) I still do not understand, how this noise can be triggered by
>     the application layer protocol (as I said, in my case: scp).

scp was probably the only protocol you were using to transfer large amounts of
data in a short period of time and so that's where the problem appeared,
when you made heavy utilization of the link

> 2.) Why do people sell TP-cables which are shielded on both ends
>     at all?

You are supposed to know not to ground both ends :)

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