[sip-clf] Vendor extensions in draft-ietf-sipclf-format-01.txt

[Anders Nygren <[e-mail]>]

Hi
I must say that I really dislike the proposed format for vendor specific fields.
Having a variable length "tag" before the length field means that it
is necessary
to scan the tag looking for the ',' just to find the length field.

There is no simple way to tell he difference between a sip-clf
optional field and
a vendor specific optional field. So it will always be necessary to scan the
record looking for the ',' .
Actually looking at RFC 5424 ch 4.3.2 it looks like this would be a legal
ID, "0001,FFFF,@12345" which would be difficult to differentiate from a
standard optional field without a lot of work.

I think a better way to do this would be similar to diameter RFC3588, ch 4.1.
Then we could have just one format for standard optional fields and vendor
specific fields

byte 1  0x09
byte 2-5 Tag (Hex)
byte 6-9 VendorId
byte 10 0x2C
byte 11-14 Length (Hex)
byte 15 0x2C
byte 16-.. Value (variable length)

Where VendorId is the IANA assigned "SMI Network Management Private
Enterprise Codes"  [ASSIGNNO] value.
VendorId=0 is used a for the standard optional fields defined in SIP-CLF.

/Anders