Custom S2B to SWu error code mapping

ePDG does supports mapping of S2B to SWu error codes so that device can identify whether it is temporary failure or permanent and can accordingly try connecting to the ePDG.

Description

The communication service providers (CSP) would like the ability to take different actions depending on the severity of the error received from the PGW (S2B interface). If there is a temporary congestion in the network, a retry is appropriate.

The ePDG needs mapping of S2B to SWu error codes for communicating different error codes to device, enabling device to identify whether its temporary failure or permanent and can accordingly try connecting to the ePDG.

The ePDG continues to release the call while notifying the UE about the S2B error, however the UE based on error code shall take decision when to try connecting again.

For the mapping ePDG uses Notify Error Message type between 31 to 8191 from the range reserved for IANA or from the private range 8192 to 16383.

Custom S2B to SWu error code mapping Configuration

Performance Indicator Changes

As part of " allow custom s2b-swu-error-mapping " feature below show commands output are introduced:

show epdg-service name

Service Name

  • Custom S2b-SWu Error Mapping

show epdg-service statistics

GTP related reasons

  • S2B Access Denied

  • S2B Network Failure

  • S2B Message Failure

  • S2B RAT Disallowed

show session disconnect-reasons

Session Disconnect Statistics

  • ePDG-s2b-access-denied

  • ePDG-s2b-network-failure

  • ePDG-s2b-msg-failure

  • ePDG-s2b-rat-disallowed

ePDG allow custom s2b-swu-error-mapping Support Bulkstats

Below Bulkstats are introduced in ePDG Schema to support s2b-swu-error-mapping Support feature:

  • sess-disconnect-s2b-access-denied

  • sess-disconnect-s2b-network-failure

  • sess-disconnect-s2b-message-failure

  • sess-disconnect-s2b-rat-disallowed