Regarding Payload ID field in the NDEF record

Jouni Malinen j
Tue Mar 11 07:05:55 PDT 2014

On Tue, Mar 11, 2014 at 06:13:47PM +0530, Jithu Jance wrote:
> Payload ID "0" seems to be mandatory as per the WPS/P2P NFC Handover
> req/select message format. But the function ndef_build_record omits
> the payload ID. Is this intentional?

Yes, it is intentional. I don't think there is any mandatory requirement
for the specific alternative carrier record to use '0' as the Payload
ID. That would not make much sense from NFC view point and I see them
more as examples for the specific messages in the spec when they
happened to include only a single alternative carrier. Any other value
could have been used instead. I would expect this to be any unique
identifier that is then used as the reference to find the data for this
particular carrier record. As such, it is up to an higher level entity
in the NFC stack to allocate a unique Payload ID and use it consistently
between the WSC, P2P, Bluetooth, etc. carrier records. (See NFC Forum
Connection Handover 1.2 spec, chapter 2.4 for more details.)

Jouni Malinen                                            PGP id EFC895FA

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