RESTful advice

[Nathaniel Auvil]

I have been a SOAP user for the past several years and am trying to create a
RESTful style architecture for the first time.  What is a best practice or
"good" way to pass things like Source System Id and other audit type
information?  IN SOAP, I would use the SOAP Header and i am thinking i do
not want to pollute my entities with extra info.  Any advice or ideas would
be greatly appreciated.