RTCH assignment failure rate increased after B11 MR3 upgrade

[djordjebeg]

Dear,

we have situation where on many bts's TCH assignment failure is very high.
After tracing we have seen that when BSC sends ASSIGNMENT COMMAND towards MS, BTS responds with assignment failure with cause"protocol error unspecified".
If we lock one TRX , TCH assignment rate is normalized.
That could not be HW issue because the problem is noticed for many BTSs.
Could be simply SW bug after B11 MR3 upgrade.

if some one have experience with the problem please share.

:@

Thanx!

[Ben0723]

what's your exactly B11 Version ? and what's the type of TRX ? Single ? Twin ? MC ? RRH ?

[djordjebeg]

Hi Ben,

We have B11MR3Ed.1.1QD04 at the moment.
In fact issue happened on TRDH , TRGH and also on Twin modules. We don't have MC or RRHs.

I checked release note for B11MR3Ed.1.3 ( latest sw) and have not seen that issue is noticed or corrected in any other network.

regards,

[Ben0723]

I think you should check with your local support team from alcatel-lucent.whether there is some AR about this problem?