Policing is allowed to borrow future traffic credits but Shaping is not ?
I was reading these slides about Shaping and Policing
On slide number three it is said that:
1)Policing is allowed to borrow future traffic credits and pay them back
2) Shaping instead uses existing credits and is not allowed to pay back
The second statement makes sense for me but I don't quite understand the second one. By my understanding Policing buckets refresh at a 1/CIR (and 1/EIR) and that means existing credit too which contradicts the first statement from above.
Could anybody help me with this ?
thanks a lot