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Fault Handling Experience: RAB Assignment Failure during Sseesion management

selim.hasan Diamond Medal

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7 years 6 months ago View: 2489 Reply: 7

1F
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Fault symptom:

The trace result shows that the SGSN sends the Activate PDP Context Reject message carrying the
0x1F cause value "Activation rejected, Protocol error unspecified" after the RNC returns the RAB Assignment Response message.

Troubleshooting:

1.Check the QoS in the RAB assignment request delivered by the SGSN in the signaling trace task. Then, check the percentage of the optional RAB bandwidth to the bandwidth of the
first RAB that is set in the SET IUSM command. Based on the QoS delivered by the SGSN and the percentage, check whether the RNC supports the QoS.

1.1 Run SET IUSM to adjust the optional RAB bandwidth range of the RNC.

1.2 Enable RAB assignment and QoS auto-negotiation and set the negotiable QoS
rate.

2.Run PING IP to check the user-plane IP connections between the SGSN and the RNC.

If the user-plane IP connections between the SGSN and the RNC fail, add the corresponding routes on the SGSN or RNC side.