5 Error Handling

08.313GPPLocation Services (LCS): Serving Mobile Location Centre - Serving Mobile Location Centre (SMLC - SMLC)SMLCPP specificationTS

In this Clause it is described how the SMLC should act in different error situations.

5.1 Missing Message Part

When a SMLC receives a Request message that does not contain one or more expected message parts (e.g. information elements, Arguments, Request ID), it sends an Error with the indication ‘Missing Message Part’ (if the operation type is known), and ignores the Request.

When a SMLC receives a Response or Error message that does not contain one or more expected message parts, it ignores the message.

5.2 Repeated Message Part

When a SMLC receives a Request message that contains one or more message parts (e.g. information elements, Arguments, Request ID) more times than expected, it sends an Error with the indication ‘Repeated Message Part’, and ignores the Request.

When a SMLC receives a Response or Error message that contains one or more message parts more times than expected, it ignores the message.

5.3 Unforeseen Message Part

When a SMLC receives a Request message that contains one or more unforeseen message parts (e.g. information elements, Result), it sends an Error with the indication ‘Unforeseen Message Part’, and ignores the Request.

When a SMLC receives a Response or Error message that contains one or more unforeseen message parts, it ignores the message.

5.4 Incorrect Data

When a SMLC receives a Request message that it can not fully understand, that contains syntax errors, or incorrect values, and no other Error Indication applies, it sends an Error with the indication ‘Incorrect Data’ (if the operation type is known), and ignores the Request. If the SMLC can not understand the operation of the Request,it just ignores the Request.

When a SMLC receives a Response or Error message that it can not fully understand, that contains syntax errors, or incorrect values, it ignores the message.

5.5 Repeated Operation

When a SMLC receives a Request message containing a Request ID, that is already in use by the same type of operation, the SMLC sends an Error with the indication ‘Repeated Operation’, and ignores the latter Request.

5.6 Unforeseen Operation

When a SMLC receives a Request for an operation that is unexpected, and none of the situations in subclause 5.5 applies,then the SMLC sends an Error with the indication ‘Unforeseen Operation’, and ignores the Request.

5.7 Unknown Request ID

When a SMLC receives a RIT Indication Request that contains a Request ID value, that is not connected to any pending RIT Query operation, or autonomous provision of RIT information, it sends a RIT Indication Error with the indication ‘Unknown Request ID’.

When a SMLC receives a RIT Query Stop that contains a Request ID value, that is not connected to any pending RIT Query operation, it sends a RIT Query Stop Error with the indication ‘Unknown Request ID’.

When a SMLC receives a Response or Error message, that contains a Request ID that is not connected to any pending operation of that type,the SMLC ignores the message.

5.8 Dublicate Request ID

When a SMLC receives a Request message containing a Request ID, that is already in use by another type of operation, the SMLC sends an Error with the indication ‘Dublicate Request ID’.

5.9 No RIT Information

When a SMLC receives a RIT Query Request, and does not have any of the requested RIT information (e.g. all cells, whose RIT information is asked for, are unknown) then the SMLC sends a RIT Query Error with the indication ‘No RIT Information’.

When during open-ended repetitive RIT indications, or autonumous provision of RIT information, there is no RIT information available, the requested SMLC refrains from sending RIT Indication Requests.

When the requesting SMLC has asked for open-ended repetitive RIT indications, but it does not receive expected RIT information, it can send a RIT Query Stop, and then a new RIT Query.

5.10 No TOA Measurements

When a SMLC receives a Perform TOA Measurement Request, and it can not perform requested measurements (e.g. it has lost connections to its LMUs, LMUs are busy, or no LMU can receive a MS) then the SMLC sends a Perform TOA Measurement Error with the indication ‘NO TOA Measurements’.

5.11 Deciphering Keys Error

When a SMLCPP receives a Send Deciphering Keys Request, and it it detects an error situation connected with the contents of the message (e.g.the SMLC acts as a controller of deciphering keys for a location area, but it receives from another SMLC keys for the same location area), it sends a Send Deciphering Keys Error message with the indication ‘Deciphering Keys Error’.

5.12 Internal Error

When a SMLCPP has any internal errors, that prevent it to act according to a Request, it can use ‘Internal Error’ indication in the Error message.

5.13 Other Error Situations

When a SMLCPP detects any other error situation when receiving a Request, it can use ‘No Indication’ indication in the Error message.

5.14 Summary of Indications

The following table summarizes the error indications, and which operations use them.

Table 1: Error Indications and operations

Error Indication

RIT Query

RIT Indication

RIT Query Stop

Perform TOA Measurement

Send Deciphering Keys

Missing Message Part

X

X

X

X

X

Repeated Message Part

X

X

X

X

X

Unforeseen Message Part

X

X

X

X

X

Incorrect Data

X

X

X

X

X

Repeated Operation

X

X

X

X

X

Unforeseen Operation

X

X

UnknownRequest ID

X

X

X

X

X

Dublicate Request ID

X

X

X

X

X

No RIT Information

X

No TOA Measurements

X

Deciphering Keys Error

X

Internal Error

X

X

X

X

X

No Indication

X

X

X

X

X