Asking ablout RAB ID is unknown in the RNC

[doanh]

Hi experts,
In some log files I analyzed , there is some dropped call cause by :

044226 18:12:52.699 RAB Config Report
Information Elements:

Altitude (m): 16
Heading (deg): 152
Speed (km/h): 18
Speed (mph): 11
---
Message:

RAB Id: Invalid, Domain: Invalid, RB Id List: [ ]

And I have read the doccument from 3GPP 25413 the rab id invalid is The action failed because the RAB ID is unknown in the RNC.
I don't know how to solve this problem . Please help me . Thanks .

[lihanbok]

Hi doand,
May be it's useful for you.

IRATCC from WCDMA RAN to GPRS, UE on Common Channel
The UE measures, evaluates, and initiates the Cell Reselection towards the
target GSM/GPRS cell. A Routing Area (RA) update is sent in the target system
by the UE that triggers the PS CN to start SRNS context transfer from the
source SRNC to source SGSN. The SRNC acknowledges the UE decision
when the message SRNS CONTEXT REQUEST is received at the SRNC. The
message includes the RABid for which the context must be transferred. At this
point anyway, no stop of the DL transmission is initiated. The SRNC sends an
SRNS CONTEXT RESPONSE message. The following step is commanded by
PS CN, which sends the IU RELEASE COMMAND message to the SRNC. Once
received by SRNC, the Iu connection is released.
Exceptional Cases
If there is an invalid RAB id in the SRNS CONTEXT TRANSFER , the SRNC
will respond withSRNS CONTEXT RESPONSE using the indicator that “RABs
Context Failed to Transfer”, due to invalid RAB id.

BR,
Lihanbok