Joint ITU-T/IEEE Workshop on The Future of Transport (Geneva, 28 May 2010) Time Awareness for Bridged LANs: IEEE 802.1 Audio Video Michael Johas Teener Sr. Technical Director, Broadcom

Geneva, 28 May 2010 Agenda

! " 802.1 AV Bridging Task Group ! " What we do

! " Why is it needed? ! " What is AV Bridging? ! " Where will it be used? ! " Possible interactions with ITU efforts

Geneva, 28 May 2010 2 IEEE 802.1 Task Group

! " Formed in late 2005 to provide the specifications that will allow time- synchronized low latency streaming services through 802 networks ! " Four projects: ! " P802.1AS: Time Synchronization (in sponsor ballot)

! " Discussed in the next presentation

! " P802.1Qat: Stream Reservation (in sponsor ballot)

! " IEEE Std 802.1Qav-2009: Forwarding and Queuing for Time-Sensitive Streams

! " P802.1BA: AVB Systems (in development)

Geneva, 28 May 2010 3 Why is it needed?

! " Common IT-oriented networks have inadequate QoS controls

! " all use 802.1 “priority” (actually, “traffic class”)

! " no time-based services, no standardized queuing or traffic shaping

! " no guarantees, timing synchronization difficult

! " Adding QoS to layer 2 networks is not enough

! " E.g., adding streaming QoS to G.hn only provides better services on a particular G.hn subnet … QoS lost going to WiFi or Ethernet

! " QoS is a NETWORK problem, not just a link problem

Geneva, 28 May 2010 4 Audio Video Bridging

Streaming AVB AVB "cloud" QoS only end (defended network) point guaranteed in AVB AVB cloud end end point point peer device not AVB legacy AVB capable AVB switch bridge switch AVB bridge end point half duplex AVB link can't AVB end do AVB end point point Enet AVB hub AVB end end point devices outside of AVB point cloud still communicate with all other devices using filtering/retagging active legacy "best effort" QoS end point best effort link streaming QoS link

! " AVB is based on 802.1Q bridges

! " The bridges connect together LANs that use different layer 2 technologies: Ethernet, WiFi, MoCA, G.hn Geneva, 28 May 2010 5 AVB provides …

! " Bounded latency … ! " For 100Mbit/sec it’s about 250 usec per link, for 1Gbit/sec it’s about 25 usec link

! " … with no dropped packets due to congestion … ! " … for streams that do not exceed their maximum bandwidth established using the end-to-end “Stream Reservation Protocol”

! " PLUS a high-quality time reference Geneva, 28 May 2010 6 AVB Will Be Used …

! " … in professional audio/video environments

! " Audio and video studios, stadiums, hospitals, airports, live performances

! " … in automotive applications ! " Infotainment, sensor systems

! " … in consumer electronics ! " Home A/V networking and interconnects ! " … in industrial systems

! " Sensors, actuators, motion control Geneva, 28 May 2010 7 AVB Provides Carrier Networks …

! " Precise synchronization services ! " 802.1AS - IEEE 1588v2 as applied to 802.1 bridged networks.

! " Much better MTIE than needed for SONET

! " Connection-oriented services ! " 802.1Qat - Stream Reservation Protocol to manage streams

! " 802.1Qav - Guaranteed latency and bandwidth for established streams

! " Removes the need for external PHY-level synchronization

! " Any 802.3 PHY will work, nothing special needed, full configuration flexibility

! " Support for other full-duplex point-to-point PHYs trivial ! " Support for shared media MACs allowed (EPON, 802.11, MoCA) via sublayer definition

Geneva, 28 May 2010 8 Putting it All Together Recovered TDM timing Differential Timing based on the differential Messages timing CE IWF IWF messages CE CE TDM IWF IWF TDM CE Packet Switched TDM Network TDM

802.1at/av

Synchronization Synchronization Network 802.1AS Network TDM Service Clocks Time Sync

PRC PRC

! " AVB supports multiple independently clocked streams/domains

Geneva, 28 May 2010 9 Thank you!

Geneva, 28 May 2010