Delete Dedicated Bearer Procedure Failure Handling

This section covers the PGW-initiated dedicated bearer deletion procedure failure scenarios.

The following table summarizes cnSGW-C behavior during different stages of the call processing for various failure types:

Note

During processing of delete dedicated Bearer Request and Response if SGW receives Context Not Found from peer (MME/UP), it deletes the PDN without performing any signaling towards the peer which sent this cause.

cnSGW-C Behavior for Delete Dedicated Bearer Procedure Failure Scenarios

Scenarios

SGW-Service Behavior

Signaling

Output

Delete Bearer Request advance validation failure

Send failure/No Signaling over Sx/MME

Negative - Delete Bearer Response to PGW

Dedicated Bearer is not deleted.

Partial Accepted: Delete Bearer Request received with multiple EBI’s, where:

  • Some EBIs belong to PDN

  • Some EBIs don't belong to PDN/Invalid EBIs

Continue DBR Procedure and delete all existing bearers for which Delete Bearer Request is received.

S11 Delete Bearer Request should carry only existing EBIs information

Sx Session Modification Request should carry existing EBIs information (Remove Traffic Endpoint)

S5 Delete Bearer Response (Cause = Partially Accepted )

S5 Delete Bearer Response where message level cause is Partially Accepted and bearer level cause is:

  • Some EBIs belong to PDN: S11 Delete Bearer Response

  • Some EBIs does not belong to PDN/Invalid EBIs: Context Not Found

CDL is updated (Remove all existing bearers)

Sx Session Modify to set action as DROP

Skip failure and continue

S5 Delete Bearer Response (Cause = Accepted)

Skip failure and continue with DBR Procedure Call Flow: Yes

S5 Delete Bearer Response (Cause = Accepted)

CDL is updated

S11 Delete Bearer Request Failure

Skip failure and continue

S5 Delete Bearer Response (Cause) = Accepted

Skip failure and continue with DBR Procedure Call Flow: Yes

CDL is updated

Sx Session Modify Request failure (Request to remove traffic endpoint on UP)

Skip failure and continue

S5 Delete Bearer Response (Cause = Accepted)

Skip failure and continue with DBR Procedure Call Flow: Yes

CDL is updated