On 15/02/2016 17:00, Joe Touch wrote: > > > On 2/13/2016 5:26 PM, Masataka Ohta wrote: >> QoS (not CoS but real QoS) capable routers must inspect L4. > > That must be why there are QoS indicators in the L4 header. > > Oh, wait - those are in L3 (RFC2474 and its successors). > > Yes, layering is a difficult concept. That's also why the IPv6 flow label is recommended to be a hash of layer 3 and layer 4 information (RFC 6437, yes, it took us some years to get that ~right). Brian