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pUbLIS
2010-06-25, 12:58 AM
Hi all

Does anyone knows how can I detect if an interface Iub is congested?

The network topology is something like this:
[NSN - NODEB] ---- [SURPASS hiD SIEMENS - ATM SWITCH] ---- [SURPASS hiD SIEMENS - ATM SWITCH] ---- [NSN - RNC]

I started to check the ATM statistics at the ATM SWITCH and I think I got the answer... none the less, I'm just guessing:

http://i463.photobucket.com/albums/qq354/pUbL1S/OPT/ScreenShot284.jpg

ATM as the capacity of discard cells if occurs congestion... In order to try to avoid discarded cells, the switch has a buffer that starts to fill hopping that the the transmission recovers. Just when the buffer is full, it starts to discard cells.

Cells are discarded according to CLP parameter... if CLP=0 they are "insured traffic" and if CLP=1 they are "best-effort traffic". Both of them are discarded, but the CLP=1 are the first to got "burned".

So.. with this information, should I look at the "Egress Queue Overflow" as the switch buffer?
I think the "Discarded cells due to" ... "Policing violation CLP=0" and "Policing violation CLP=0+1" are self explanatory.

Am I right?

Cheers m8s