Charging ID in GGSN

Dear reader,

The charging ID is unique for every PDP context. It is generated by GGSN during the PDP context activation. What I fail to understand is:

  1. When there are multiple PDP context (Primary and secondary) from the same UE with different TEIDs, should the charging Id be different for two pdp contexts?
  2. If there is an update PDP context request from new SGSN during RAU, and if there is a new TEID(is it possible?), will the charging ID for the new tunnel be same?

Thank you for your response