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EngSoft
2010-02-22, 04:50 PM
Dears,

Am doing a DT analysis and i found that for some reason i keep having N200 timeout .

as all know the N200 is a layer 2 timer and if define the number of retransmission in LAPD frams .

LAPD is between the BTS and BSC , so my question what could cause the timer to finish.

I think , it could be no stability in transmission (E1) , what you think ??

please advice

:confused:

RF engineer
2010-02-22, 05:34 PM
Dears,

Am doing a DT analysis and i found that for some reason i keep having N200 timeout .

as all know the N200 is a layer 2 timer and if define the number of retransmission in LAPD frams .

LAPD is between the BTS and BSC , so my question what could cause the timer to finish.

I think , it could be no stability in transmission (E1) , what you think ??

please advice

:confused:

N200 or T200 ?
BR
RF

EngSoft
2010-02-22, 09:25 PM
N200 . T200 is other thing

RF engineer
2010-02-22, 11:08 PM
N200 . T200 is other thing
Hi
No, both of them related to each other but i never faced such a problem for N200 and face T200 expired may be other colleague may be helping
BR
RF

hassen
2010-02-23, 03:44 AM
Hi
the mobile station stops the transmitting of measurement reports
the BTS never get an acknowledge on a Layer 2 message after the time T200
LAPD N200 is the maximum number of retransmissions

br hassen

tukangoptim
2010-02-23, 04:17 AM
example time out when channel ass cmd during HO.
mostly due to radio quality. or if TRanscodre timer also expired abis subslot perhaps problem.

http://i49.tinypic.com/razp84.gif

wael
2011-01-14, 07:30 PM
Usually this timer N200 come with T200 during establish the SABAM message which is in Layer 2 during the assaying the channels in the call setup(SDCCH) or during the handover(FACH/FullTCH, FACH/half TCH ) , in the TEMs will see the N200 time out come with handover failure and with data link failure and like this case can be come due to :
· Link transmission
· TEMS ( there is problem in the TEMS)
· hardware issue in the Maine processer in the BTS itself causing delay .
· Bad RxQual UL

kadry
2011-01-15, 09:01 PM
N200:means the number of resend SDCCH to moble station
The value specifies the maximum number of retransmitting a frame
Timer T200 has expired N200 +1 times (MS does not respond any more).
check if there is:
bad coverage
high interference
hardware faulty

thanks