Subject: [IPFIX] two issues for RFC5102bis

From: Paul Aitken <[email-masked]>
Date: Tue, 20 Dec 2011 14:52:46 +0000

Dear IPFIX experts,

Two issues for RFC5102bis:

Firstly, can we recognise that unsigned8, unsigned16, unsigned32, and 
unsigned64 aren't different types; they're simply different lengths of 
the same type. Accordingly, we should use a single "unsigned" type.

Similarly for signed.

Else, when using reduced size encoding to export unsigned64, the 
implication is that the _type_ changes? Clearly this isn't the case.

The encoding of float32 and float64 differs, so these should remain as 
different types.

Secondly, the info model should not specify the field size since sizes 
are specified in the template.

There was one argument that the maximum length must be specified for 
collector database design. This is only an issue if differently-sized 
fields are stored in the same database - eg, the database field is only 
8 bits wide, and is suddenly required to store a 16- or 32-bit wide 
field. This may only be an issue in an IPFIX aggregator.

If this is a real issue, then the infomodel should specify the maximum 
length for each field, rather than confusing this with the field type.

Thanks,
P.