[ASN.1] Doubt on tag implementation

[manikandan]

hi,   In the following structure both digitsCarrier and digitsDestination having same tag number and both are optional.   Digits ::= OCTET STRING (SIZE(5..200))   LocationRequestRRL ::= [PRIVATE 18] SET {     electronicSerialNumber                  [9]         ElectronicSerialNumber,     mobileIdentificationNumber            [8]         MobileIdentificationNumber,     mSCID                                          [21]        MSCID,     accessDeniedReason                      [20]        AccessDeniedReason                  OPTIONAL,     announcementList                           [130]       AnnouncementList                    OPTIONAL,     callingPartyNumberString1             [82]        CallingPartyNumberString1           OPTIONAL,     callingPartyNumberString2             [83]        CallingPartyNumberString2           OPTIONAL,     digitsCarrier                                   [4]         Digits                       OPTIONAL,     digitsDestination                             [4]         Digits                   OPTIONAL,     displayText                                    [508190]    DisplayText                         OPTIONAL,     dMH-AccountCodeDigits              [140]       DMH-AccountCodeDigits               OPTIONAL,     dMH-AlternateBillingDigits            [141]       DMH-AlternateBillingDigits          OPTIONAL,     dMH-BillingDigits                          [142]       DMH-BillingDigits                   OPTIONAL,     dMH-RedirectionIndicator             [88]        DMH-RedirectionIndicator            OPTIONAL,     groupInformation                           [163]       GroupInformation                    OPTIONAL,     mobileDirectoryNumber                [93]        MobileDirectoryNumber               OPTIONAL,     noAnswerTime                              [96]        NoAnswerTime                        OPTIONAL,     oneTimeFeatureIndicator               [97]        OneTimeFeatureIndicator             OPTIONAL,     pC-SSN                                       [32]        PC-SSN                              OPTIONAL,     redirectingNumberDigits                [100]       RedirectingNumberDigits             OPTIONAL,     redirectingNumberString                [101]       RedirectingNumberString             OPTIONAL,     redirectingSubaddress                   [102]       RedirectingSubaddress               OPTIONAL,     resumePIC                                   [508170]    ResumePIC                           OPTIONAL,     routingDigits                                 [150]       RoutingDigits                       OPTIONAL,     terminationList                              [120]       TerminationList                     OPTIONAL,     terminationTriggers                     [122]       TerminationTriggers                 OPTIONAL,     triggerAddressList                      [508180]    TriggerAddressList                  OPTIONAL }   How this two will be differetiated while decoding and encoding? How this duplicate tags will be handled in ASN.1 encoding and decoding?   Please let me know the answer.   thanks in advance Regards _________________________________________________________   Manikandan .M             Phone  : 91-80-5202947 / 48 Software Engineer,        Mobile  : 91-98455 14960 Intellinet Technologies,  Fax      : 91-80-51150427 Oxford Towers,                   Unit 413/4,3rd Floor,      E-mail  : [EMAIL PROTECTED] 139, Airport Road,          web     : http://intellinet-tech.com Bangalore - 560017 _________________________________________________________