Supporting Larger Source to Target Container IE in Handover

Feature Summary and Revision History

Summary Data

Applicable Product(s) or Functional Area

MME

Applicable Platform(s)

  • ASR 5500

  • VPC-DI

  • VPC-SI

Feature Default

Enabled - Always On

Related Changes in This Release

Not applicable

Related Documentation

  • MME Administration Guide

Revision History

Revision Details

Release

First Introduced.

21.19.6

Feature Changes

Previous Behavior: If S1 Handover includes Source-to-Target-Transparent Container IEs of size greater than 5499 bytes, S1 Handover requests was rejected with ERROR INDICATION (15) and caused Abstract-syntax-error.

New Behavior: MME increased the maximum size of the Source-to-Target-Transparent Container IE from 5499 bytes to 9000 bytes to support the increase in the size of UE radio capabilities driven by additional bands that is supported by RAN specifications and support of significantly more band combinations by UE.

Limitations

The limitations are:

  • General Limitation: Supports only Larger source eNodeB to target eNodeBE container IE.

  • S1HO Limitation:

    • The maximum supported size of s1ap packet is 9216.

    • Though the size of IE is less than or equal to 9000, if the size of the packet exceeds 9216, then the packet will be dropped.

  • S10HO Limitation:

    • The maximum supported packet size is 9188 for VPC platforms.

    • The maximum supported packet size is 7000 for ASR5500 platforms.

    • This limit includes Internal Header + IPv4/Ipv6 Header + UDP Header+ GTPV2 Header + GTV2 Message (Other IEs + Source to Target Container IE).

    • Though the size of IE is less than or equal to 9000, if the size of the packet exceeds 9216, then the packet will be dropped.

    • The Larger Source to Target Container IE in Handover functionality is not supported when the peer fallsback to Gtpv1.

Monitoring and Troubleshooting

This section provides information regarding show commands.

Show Commands and Outputs

show mme-service-statistics-s1ap

The output of this command includes the following fields

Protocol Error Statistics:
   Transmitted:
    Transfer Syntax Error:              0  Semantic Error:                     0
    Message Not Compatible:             0
    Abstract Syntax Error:
      Reject:                           0  Ignore And Notify:                  0
      Falsely Constr Msg:               0
Large Packet: 0 >>>> new counter

   Received:
    Transfer Syntax Error:              0  Semantic Error:                     0
    Message Not Compatible:             0
    Abstract Syntax Error:
      Reject:                           0  Ignore And Notify:                  0
      Falsely Constr Msg:               0
Large Packet: 1 Large Container IE: 1 >>>> New counters