Discussion on IEEE802.1Qbv Time-Aware Shaper and scheduled (time-driven) traffic ongoing at IEEE802 plenary meeting in San Diego, CA ...
By adding time-driven packets and time-aware shaper, packets with fixed end-to-end latency can be forwarded in multi-hop Ethernet networks.
Right now (18 July 2012) there is an ongoing discussion how scheduled traffic can be integrated and forwarded in the switch, together with best effort and time-sensitive traffic.
Also see Project Authorization Request (PAR)
... and some background considerations:- http://www.ieee802.org/3/cfi/0312_4/cfi_0312_4.pdf