第1章             问题原因

1.1   问题描述

2011-07-01日发现某地ETC失败。经抓取trace发现，scp发向某地软交换的correlationid,某地软交换发向IP的correlationid不一致。

我们发现某地软交换把a转成了0,将f转成了a。

测试中的AA软交换、BB软交换透传correlationid,它们的ETC都是成功的。

1.2   问题分析

对于SCP，SSP，IP交互过程 ITU-T Q.1218对其描述如下：

Q.1218 第16(4)页：

可以看出ssp需要支持传输correlationinformation

Q.1218 3.1.2.5.1 第146(134)页 开始详细介绍了 SRF connect procedures过程

3.1.3.5.1 SRF connect procedures

3.1.3.5.1.1 SRF connect physical procedures

Several procedures are required for different physical scenarios. The cases to be covered are described below and

illustrated in Figure 26:

i) the IP is integrated into the SSP, or directly attached to the SSP, that is interacting with the SCP but

the SCP’s operations to the IP are relayed via the SSP which performs any needed protocol conversion;

ii) the IP is directly attached to the SSP that is interacting with the SCP but the SCP’s operations to the IP

are sent directly to the IP without SSP relaying involved;

iii) the IP is integrated into another SSP, or directly attached to another SSP, than the one that is interacting

with the SCP but the SCP’s operations to the IP are relayed via the second SSP (called the “Assist”

method), and on completion of the user interaction, control is returned to the first SSP;

iv) the IP is directly attached to a node other than the SSP that is interacting with the SCP but the SCP’s

operations to the IP are sent directly to the IP without SSP relaying involved (called the “Assist” method,

but with a variation on the physical connectivity of the entities involved), and on completion of the user

interaction, control is returned to the first SSP; and

v) the IP is attached to another SSP and on completion of the user interaction, control of the call is retained

at that SSP (called the “Handoff” approach).

In each of the above cases, the operations between the SCP and the SSP may be SS No. 7 TCAP-based; the messaging

between the SSP and the IP when the SSP does relaying may be DSS 1 using the facility IE (in this case, the SSP would

have to do protocol conversion from SS No. 7 TCAP to DSS-1 facility IE for the operations and responses it relayed

between the SCP and the IP); the direct messaging between the SCP and the IP may be SS No. 7 TCAP based; and

bearer control signalling may be any system.

Each of the scenarios will now be examined using arrow diagrams.

Case i) is illustrated in Figure 27. Note that for the integrated IP/SSP, the internal activities of the node can still be

modelled in this way, but the details of how this is achieved are left to the implementor. This approach makes it

unnecessary for the SCP to distinguish between integrated and external but directly connected IPs. See also a note on the

possibility of concatenating the first user interaction operation with the ConnectToResource operation discussed in the

subclause on user interaction below. The establishment of the SCF-SRF relationship in this case is implicit.

Case ii) requires that the IP indicate to the SCP that it is ready to receive operations (see Figure 28). The establishment

of the SCF-SRF relationship is explicit. Note that it is necessary to convey a correlation ID to ensure that the transaction

established between the SCP and the IP can be correlated to the bearer connection set-up as a result of the SCP’s

preceding operation to the SSP.

Case iii) requires that a transaction be opened with the assisting SSP so that it may relay operations from the SCP to

the IP (integrated or external). Once the bearer control signalling has reached the assisting SSP, it triggers on the identity

of the called facility, and initiates an interaction with the SCP that has requested the assistance. It would also be possible

to trigger on other IEs such as the incoming address. The bearer control signalling must contain information to identify

the SCP requesting the assistance, and a correlation ID. This information may be hidden in the address information in

such a way that non-message based signalling systems may also be used to establish the bearer connection to the

assisting SSP. After the AssistRequestInstructions are received by the SCP, the procedures are the same as in case i).

Figure 29 illustrates the preamble involved.

Case iv) does not require the establishment of a second transaction from the assisting exchange, hence it need not be

an SSP. This then becomes a preamble to the procedure shown in Figure 28 as shown in Figure 30.

Case v) merely requires the sending of an operation to the first SSP to route the call to the handed-off SSP, and then

Figure 27 applies at handed-off SSP. This is shown in Figure 31. Note that the activity at handed-off SSP represents a

new interaction with the SCP and “AssistRequestInstructions” is used. Once the bearer control signalling has reached the

assisting SSP, it triggers on the identity of the called facility, and initiates an interaction with the SCP that has requested

the assistance. It would also be possible to trigger on other IEs such as the incoming address. The bearer control

signalling must contain information to identify the SCP requesting the assistance, and a correlation ID. This information

may be hidden in the address information in such a way that non-message based signalling systems may also be used to

establish the bearer connection to the assisting SSP.

彩铃的处理应该是case iii ,其中我们可以看到需要ssp对correlation进行透传，这样ip scp ssp 三者可以连接起来。

ITU-T Q.763   对correlation id的解释

Q.1218 58(46)页

CorrelationID ::= Digits

-- used by SCF forcorrelation with a previous operation. Refer to clause 3 for a description ofthe

-- procedures associated with this parameter.

-- The following parameters should use Generic Number:

-- CorrelationID for AssistRequestInstructions, AssistingSSPIPRoutingAddress for

-- EstablishTemporaryConnection, calledAddressValue for all occurrences, callingAddressValue for all

-- occurrences. The following parameters should use Generic Digits: prefix, all

-- other CorrelationID occurrences, dialledNumber filtering criteria, callingLineID filtering criteria, lineID

-- for ResourceID type, digitResponse for ReceivedInformationArg.

可以看出在ETC中，correlationid编码规则是Generic digis.

Q.763对Generic Digits的解释为：

从下面的trace：

[23:26:05] FSM 925, 75 bytes, Received fromSS7 ( TC-Begin ):
0    00 0B 01 29 B9 4F 0D 81  0C 05 4386 03 16 0C 00   ...).O....C.....
16   FF 08 03 A3 7D 01 01 01  00 00 23FF 00 05 43 29   ..........#...C)
32   14 16 0C 38 A0 29 B9 4F  0D FF 0140 86 07 00 13   ...8.).O...@....
48   38 24 91 40 56 87 0A 81  10 1B 0081 27 58 01 69   8$.@V.......'X.i
64   03 88 0A 83 10 80 52 81  27 FF00                  ......R.'..
TC-Begin.Ind:
 QualityOfService = { ReturnOption:81, SequenceControl:0C }
 DestinationAddress
   PC = 8782614
   SSN = 12
 ApplicationContextName = 03 A3 7D 01 01 01 00 00
 OriginatingAddress
   PC = 2692118
   SSN = 12
 DialogueID = 700010253
 ComponentsPresent = Present
[23:26:05] FSM 925, 86 bytes, Received fromSS7 ( TC-Invoke ):
0    00 0B 10 29 B9 4F 0D 29  B9 4F 0DFF 01 FF 00 00   ...).O.).O......
16   FF FF 03 A3 7D 00 3F 30  3D 80 0200 EF 82 07 01   ......?0=.......
32    10 3B 21 24 43 10 83 08  83 10 20 88 71 01 90 09   .;!$C..... .q...
48    85 01 0A 87 01 00 88 02  01 3E 89 01 01 AB 03 80   .........>......
64    01 00 8C 07 03 00 18 66  96 39 09 9C 01 0C 9D 06   .......f.9......
80   81 10 66 99 93 00                                  ..f...
[23:26:05] FSM 925, Received TC-Invoke Ind( 0 )
TC-Invoke.Ind:
 DialogueID = 700010253
 InvokeID = 01
 OperationID = 0
 LastComponent = Last
MsgID[ 0]
+---c[   30]
   +---p[    80]       2      00 EF
    +---p[   82]       7       01 10 3B 21 24 43 10
    +---p[   83]       8       83 10 20 88 71 01 90 09
    +---p[   85]       1       0A
    +---p[   87]       1       00
    +---p[   88]       2       01 3E
    +---p[   89]       1       01
    +---c[   AB]
    |   \---p[   80]       1       00
   +---p[    8C]       7      03 00 18 66 96 39 09
   +---p[    9C]       1      0C
   \---p[    9D]       6      81 10 66 99 93 00
###START:start(925-700010253,tcInvoke_0)...ret(1,0),next[ ]Check_NumFormat
###Check_NumFormat:Branch(925-700010253,NULL)...ret(3,0),next[ ]beijiao
###beijiao:Algorithm(925-700010253,NULL)...ret(1,0),next[ ]chaxun
###chaxun:ExecSQL(925-700010253,NULL)...[23:26:05]FSM 925, DB[sdp@sc5_sdp2], ecSelect:
select newnumber , usertype , calltimes ,calldate from change_nbr_user where oldnumber = '081666993
90' and endTime >= '20110701232605'
[23:26:05] FSM 925, Select Result:rowNum=1, fieldNum=4
 newnumber   usertype  calltimes  calldate
  (CHAR20)   (CHAR23)   (CHAR23)   (CHAR8)
15378238840          1         73  20110701
ret(1,0), next[ ]Edprequest1
###Edprequest1:Xmlsib(925-700010253,NULL)...[23:26:05]FSM 925, Send TC-Invoke Req( 23 )
TC-Invoke.Req:
 DialogueID = 700010253
 OperationType=2
 InvokeID = 81
 OperationID = 23
 Timeout = 100
RequestReportBCSMEvent-os:
\---RequestReportBCSMEventArg
   \---bcsmEvents
       +---eventTypeBCSM       1   09
       +---monitorMode         1   01
       \---legID
           \---sendingSideID       1   01
       +---eventTypeBCSM       1   0A
       \---monitorMode         1   01
[23:26:05] FSM 925, 48 bytes, Send to SS7 (TC-Invoke ):
0    00 01 10 29 B9 4F 0D 29  B9 4F 0D02 81 FF 00 17   ...).O.).O......
16   FF 00 00 00 64 00 19 30  17 A0 1530 0B 80 01 09   ....d..0...0....
32   81 01 01 A2 03 80 01 01  30 06 8001 0A 81 01 01   ........0.......
ret(1,0), next[ ]PA_Sound
###PA_Sound:Algorithm(925-700010253,2)...ret(1,0),next[ ]SspnameBan1
###SspnameBan1:Branch(925-700010253,NULL)...ret(10,0),next[ ]To_ETC
###To_ETC:UI(925-700010253,NULL)...[23:26:05]FSM 925, Send TC-Invoke.Req( EstablishTemporaryConnect
ion )
TC-Invoke.Req:
  DialogueID = 700010253
  OperationType=2
 InvokeID = 82
 OperationID = 17
 Timeout = 100
assistingSSPIPRoutingAddress="419711"
correlationID="ab0925"
NOT PRESENT
scfID=NOT PRESENT
serviceInteractionIndicators=NOT PRESENT
[23:26:05] FSM 925, 39 bytes, Send to SS7 (TC-Invoke ):
0    00 01 10 29 B9 4F 0D 29  B9 4F 0D02 82 FF 00 11   ...).O.).O......
16    FF 00 00 00 64 00 10 30  0E 80 06 01 02 10 14 79   ....d..0.......y
32    11 81 04 00 BA 9052                              ......R
TC-Continue1.Req:
  QualityOfService = {ReturnOption:81, SequenceControl:0C }
 OriginatingAddress
   PC = 8456214
    SSN = 240
  ApplicationContextName = 03 A3 7D 01 01 01 0000
  DialogueID = 700010253

我们SCP在实际下发ETC时，correlationid是符合Q.763标准的。

第2章             解决说明

解决现网问题有如下方案：

请某地交换透传correlationid，不要讲a转成0,将f转成a。