A Interface Cause Codes

DESCRIPTION

1/1551-CRT 240 09 Uen B

A-Interface Cause Codes Copyright © Ericsson AB 2005 - All Rights Reserved Disclaimer No part of this document may be reproduced in any form without the writtenpermission of the copyright owner. The contents of this document aresubject to revision without notice due to continued progress in methodology,design, and manufacturing. Ericsson shall have no liability for any erroror damage of any kind resulting from the use of this document. Trademark List Ericsson is a trademark owned by Telefonaktiebolaget LM Ericsson. All other product or service names mentioned in this Description are trademarks of their respective companies.

Contents 1 1.1 1.2

General Revision Information Introduction

2 2.1

Messages Sent from the BSC Clear Request

3

Glossary

4

Reference List

1 General 1.1 Revision Information This document is based upon 1/1551-CRT 240 09, revision A. The document is changed as below: More detailed explanation that statistic counters for dropped connections are not stepped according to cause value, is added in Section 2.1.1.. 2.1.1





Some editorial changes. Chapter 3 and 4 are added.

1.2 Introduction In some 48.008 messages sent between the BSC and the MSC the Information Element (IE) Cause is included (see Reference [1]). [1]). The purpose of the IE is to explain to the receiving node why a message is sent. It can be an order to act on a connection or a resource, or it can be to explain why a given orde r could not be executed. In this document the values of IE Cause of message CLEAR REQUEST is described. In Section 2.1.1 the relation between CLEAR CL EAR REQUEST and statistic counters is also described.

2 Messages Sent from the BSC 2.1 Clear Request 2.1.1

General

The CLEAR REQUEST message is sent to the MSC when BSS has detected a fault that severely affects the connection. The message contains the IE Cause that indicates the reason for the release. When CLEAR REQUEST is sent to the MSC, at least one statistic counter is stepped indicating that a connection is dropped. The counters for dropped calls are not related to the cause value sent in the CLEAR REQUEST message. Which counter to be stepped is only decided according to type of channel, channel rate and subcell. Additional statistic counters are stepped if urgency state applies. Independent of cause value the BSC checks if urgency state is indicated for the dropped connection. If urgency state is indicated, some counter indicating urgency condition is stepped. Which counter depends on the type of urgency state, type of channel and channel rate (see Reference [2]). [2]). 2.1.2

Cause values

The following cause values can be sent from the BSC in CLEAR REQUEST. Cause 0=Radio 0=Radio Interface message failure

Reason Air interface

Detected by BSC

Excessive TA Too many measurement generations missing Too many measurement generations missing and excessive TA Air interface

BSC

MS lost at Assignment Command or Handover Command Air interface BTS

T200 expired Unsolicited DM response in multiple frame established state

1=Radio Interface Failure

Sequence error HW, GS fault Air interface, for prioritized mobile that is queued

BSC/TRC BSC

Excessive TA Too many measurement generations missing Too many measurement generations missing and excessive TA 32=Equipment HW Failure

BSC/TRC

Transcoder resource fault Other equipment failure Abis

BSC/BTS

LAPD link disturbance LAPD link fault TRA or transmission device fault BTS fault report class 1 Abis

BTS

Transmission failure Ater

BSC/TRC

Transmission setup failure timeout on Ater SCCP connection failure Reset Circuit from TRC Terrestrial resource failure Manual intervention

BSC/TRC

Blocking of transcoder Manual intervention

BSC

Blocking BPC

Load BPC Function change BPC New SW started BPC Air interface

BTS

Connection failure to MS at handover Air interface

BSC

Terrestrial resource failure 32=Equipment Other Failure (continue) Operational recovery failed

BSC

The BPC is being created or is about to be deleted Reconfiguration of BTS equipment 1 Reconfiguration of BTS equipment 2 TAS system error TRXC failure TGC changeover failure Other 33=No Radio No radio resource available, timeout of  Resource assignment timer (T_ASSREQ) for priority Available connection 34=Requested A-int -inter erfface, ace, terre errest stri ria al res resou ourc rce e una unavai vailabl lable e terrestrial resource unavailable 41=Preemptio Preemption n 80=Terrestrial A-interface, te terrestrial re resource al allocated circuit already allocated 86 Excessive TA (SDCCH) 87 Excessive TA (TCH/F) 88 Excessive TA (TCH/H) 89 Suddenly lost connections (TCH/F) 90 Suddenly lost connections (TCH/H) 91 Suddenly lost connections, overlaid subcell (TCH/F) 92 Suddenly lost connections, overlaid subcell (TCH/H)

BSC

BSC BS C

BSC BSC

BSC BSC BSC BSC BSC BSC BSC

98 99 1 00 1 01 1 02 1 03 1 04 1 05 1 06 1 07 1 08 1 09 1 10 1 11 1 12 1 13 1 14 1 15 1 16 1 17 1 18 1 19 1 20 1 21 1 22 1 23 1 24 1 25

Low signal strength down or uplink per cell (SDCCH) Low signal strength down or uplink per overlaid subcell (SDCCH) Low Signal Strength, bothlink (TCH/F) Low Signal Strength, bothlink (TCH/H) Low Signal Strength, overlaid subcell (TCH/F) Low Signal Strength, bothlink, overlaid subcell (TCH/H) Low Signal Strength, downlink (TCH/F) Low Signal Strength, downlink (TCH/H) Low Signal Strength, downlink, overlaid subcell (TCH/F) Low Signal Strength, downlink, overload subcell (TCH/H) Low Signal Strength, uplink (TCH/F) Low Signal Strength, uplink (TCH/H) Low Signal Strength, overlaid subcell (TCH/F) Low Signal Strength, uplink, overlaid subcell (TCH/H) Low quality, down or uplink per cell (SDCCH) Low quality, down or uplink per overlaid subcell (SDCCH) Bad quality, bothlink (TCH/F) Bad quality, bothlink (TCH/H) Bad quality, bothlink, overlaid subcell (TCH/F) Bad quality, bothlink, overlaid subcell (TCH/H) Bad quality, downlink (TCH/F) Bad quality, downlink (TCH/H) Bad quality, downlink, overlaid subcell (TCH/F) Bad quality, downlink, overlaid subcell (TCH/H) Bad quality, uplink (TCH/F) Bad quality, uplink (TCH/H) Bad quality, uplink, overlaid subcell (TCH/F) Bad quality, uplink, overlaid subcell (TCH/H)

BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC BSC

The cause values 86 - 125 can only be received when reporting of Dropped Call Reason to the MSC is activated (command RAEPC). If Dropped Call Reason to the MSC is inactive the cause value 0 or 1 is received instead.

3 Glossary BPC Basic Physical Channel BSC Base Station Controller BSS Base Station System

BTS Base Transceiver Station HW Hardware IE Information Element LAPD Link Access Protocol on the D-channel MSC Mobile Services Switching Centre TA Timing Advance TGC Transceiver Group Controller TRA Transcoder and Rate Adapter TRC Transcoder Rate Adaptor Controller TRXC Transceiver Controller

4 Reference List [1] 3GPP TS 48.008, 48.008, (GSM Specification) Mobile Switching Centre - Base Station System (MSC-BSS) Interface Layer 3 Specification. [2] Counters in the Measurement Data Base for Traffic and Event Measurements in Radio Network , (Function Specification) Specification)