Re: [Sigtran] Interface Identifier in ASPTM message in M2UA

["Brian F. G. Bidulock" <[e-mail]>]

rajangam.subramanian,

Well, no.

3.2 applies to MAUP messages only.  MAUP messages are specific to an
interface.  MAUP messages control the MTP2 signalling link and therefore
must identify a specific signalling link.  Therefore, the Integer IID
can only identify a single signalling link for MAUP messages and the
length needs to be 8.  Note also that, although text IIDs are also
supported, IID ranges are not.

ASPTM messages, OTOH, specify a group of IIDs that belong to an AS.  An
AS can consist of more than one signalling link.  (See 1.5.1: "An AS MAY
support more than one Interface Identifier.")  Therefore, the ASPAC and
ASPAC Ack messages can have multiple Integer IIDs.  As shown in 3.3.2.7,
the IID can have a length 4+n*4, where n is the number of integer
interface identifiers in the parameter, or, as also shown, can have
repeated parameters, each with one or more integer IIDs.  The message
can also have multiple Integer range IIDs or multiple text IIDs.

There is no error.  There is no contradiction.  This is completely in
fitting with the intended use of the protocol.

--brian

[e-mail] wrote:                 (Wed, 07 Sep 2011 14:18:41)
>    Hello Sandeep Singh and all,
> 
>       I differ from your inference of the section 3.3.2.7 (Page 36 RFC
>    3331). It would be in conflict to section 3.2 (Page 22 of RFC 3331)
>    which actually defines the structure of the Interface Identifier.
>    Section 3.3.2.7 gives an indication of the possible parameters in the
>    ASPAC message but does not define the structure of the parameters (Of
>    course there is an ambiguity in the RFC or rather error, wherein in
>    section 3.2 indicates M2UA specific headers are used only with MAUP
>    messages while they are used also with other messages like ASPSM
>    messages).
> 
> 
>    So from the structure of the Integer Interface Identifier we need to
>    follow section 3.2 which clearly states the length value cannot be
>    greater than 8.
> 
> 
>    Regards,
> 
>    Rajangam

-- 
Brian F. G. Bidulock
[e-mail]
http://www.openss7.org/