Hi All,
I have to decode the SABP protocol i.e 3GPP TS 25.419 and have a doubt whether certain fields will be arriving in the data. The coding has to be done in PER(Aligned)
 
Fo example : There is a message called Write-Replace-Complete, the definition of which is as follows

Write-Replace-Complete ::= SEQUENCE {

protocolIEs ProtocolIE-Container { {Write-Replace-Complete-IEs} },

protocolExtensions ProtocolExtensionContainer { {Write-Replace-Complete-Extensions} } OPTIONAL,

...

}

Write-Replace-Complete-IEs SABP-PROTOCOL-IES ::= {

{ ID id-Message-Identifier CRITICALITY reject TYPE Message-Identifier PRESENCE mandatory } |

{ ID id-New-Serial-Number CRITICALITY reject TYPE New-Serial-Number PRESENCE mandatory } |

{ ID id-Number-of-Broadcasts-Completed-List

CRITICALITY reject TYPE Number-of-Broadcasts-Completed-List

PRESENCE mandatory }|

{ ID id-Criticality-Diagnostics

CRITICALITY ignore TYPE Criticality-Diagnostics PRESENCE optional },

...

}

Write-Replace-Complete-Extensions SABP-PROTOCOL-EXTENSION ::= {

...

}

 

The CLASS definition of SABP-PROTOCOL-IES is

SABP-PROTOCOL-IES ::= CLASS {

&id ProtocolIE-ID UNIQUE,

&criticality Criticality DEFAULT ignore,

&Value,

&presence Presence

}

WITH SYNTAX {

ID &id

CRITICALITY &criticality

TYPE &Value

PRESENCE &presence

}

 

and the CONTAINER definitions are:

ProtocolIE-Container {SABP-PROTOCOL-IES : IEsSetParam} ::=

SEQUENCE (SIZE (0..maxProtocolIEs)) OF

ProtocolIE-Field {{IEsSetParam}}

ProtocolIE-Field {SABP-PROTOCOL-IES : IEsSetParam} ::= SEQUENCE {

id SABP-PROTOCOL-IES.&id ({IEsSetParam}),

criticality SABP-PROTOCOL-IES.&criticality ({IEsSetParam}{@id}),

value SABP-PROTOCOL-IES.&Value ({IEsSetParam}{@id})

}

Also in the common definitions it has been given

Presence ::= ENUMERATED { optional, conditional, mandatory }

The thing I would like to know is whether the PRESENCE field will also come in the live data and whether criticality field will be treated as optional(as specified in the CLASS definition) or mandatory.

 

Any help on this will be highly appreciated.

Thanks in advance.

Roohi 

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