Bag - what is this ?

Hi

I'm currently trying to work out what my iPhone is talking to. It's making some requests to http://pds-init.ess.apple.com/WebObjects/PdsInit.woa/wa/getBag?ix=3

which seems to be a XML file, with some PEM encoded bits. I've included this below.

I suspect that this might be APNS, but I'm not sure.

Does anyone know what this is used for please ?

many thanks

Bag - what is this ?
 
 
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