Summary Data

Revision History

The User Equipment (UE) suffers failure, during attach process with an EMM Attach Reject message sent from MME to UE. When UE attach request is sent from MME to P-GW, the DNS server responds back with “Server failure", causing the MME to reject the UE attach request with the following error messages:

1. EMM Cause Code 17 Network Failure

2. ESM PDN Connectivity Reject Container message with ESM Cause Code 31 Request Rejected Unspecified.

To overcome the impact in MME 4G attach SR calculations, the Cause Codes introduced in the EMM Attach Reject/ESM PDN Connectivity Reject message to be EMM Cause Code 19 ESM Failure and ESM Cause Code 27 Missing or Unknown APN, instead of the current cause codes EMM 17 and ESM 31.

To overcome the UE attach request failure, the following new configuration commands are introduced:

1. ESM-failure with EMM Cause Code

2. ESM-cause-code with ESM Cause Code option missing-or-unknown-apn

Use the following configuration commands to enable cause code mapping under mme-service:

configure  
   context context_name  
      mme-service service_name { local-cause-code-mapping{ pgw-selection-failure( emm-cause-code ){ esm-failure ( esm-cause-code )( unknown-apn ) }}} 
        end 

Use the following configuration commands to enable cause code mapping under call control profile:

configure   
      call-control-profile profile_name { local-cause-code-mapping{ pgw-selection-failure( emm-cause-code ){ esm-failure ( esm-cause-code ) ( unknown-apn )}}} 
        end 

show mme-service all

The output of this command displays the following newly introduced field:

show call-control-profile full all

The output of this command displays the following newly introduced field: