HomePlug AV Technical Overview ISPLC 2006 – Orlando, FL March 28, 2006 Larry Yonge HomePlug AV TWG Chair

Copyright © 2005, HomePlug Inc HomePlug AV Marketing Requirements  Focus segment – In-home connectivity –Consumer Electronics (STB, HDTV, DVD, Audio)  Focus applications –Video and Audio distribution –Voice and Data  Performance Requirements –>100 Mbps class, whole home coverage for high quality streaming media Reliable, secure delivery with low latency and jitter –Efficient use of available system capacity, with graceful degradation –Acceptable for encrypted, copy protected content with DRM  Coexistence –HP 1.0 –Easy bridging to other networking technologies  Coverage –At least 98% of outlet pairs must support a single 24Mbps HDTV stream –At least 90% of outlet pairs must support two simultaneous 24Mbps HDTV streams  Competitive cost

Copyright © 2005, HomePlug Inc System Architecture

Copyright © 2005, HomePlug Inc PHY Highlights  Windowed OFDM –Spectral notching for preamble, frame control and payload –917 carriers (excluding Amateur bands)  Bit-loaded modulation: BPSK to 1024QAM –Optimum adaptation for each connection  Turbo FEC for frame control, beacon, payload –16, 136 and 520 byte block sizes respectively –Near capacity performance (1/2 dB from Shannon Capacity)  Channel interleaver for impulse noise and other PL impairments  Diversity coding for reliable frame control, beacon and ROBO  HP1.0 coexistence mode uses 1.0 frame control –AV preamble can be detected by 1.0 devices  200 Mbps PHY channel rate –150 Mbps PHY information rate

Copyright © 2005, HomePlug Inc PHY Spectrum channels from 2-28 MHz  Tone Mask defined for North America  Amplitude Map enables additional nulls while maintaining interoperability Power Spectral Density Vs Frequency Nulls created simply through configuration. Spectral nulls required to avoid interference with amateur bands. Different rules in different countries

Copyright © 2005, HomePlug Inc PHY Channel  Frequency selective channel is unique for each connection  Time varying noise and impulse response is common Frequency Selective Channel Time Selective Channel

Copyright © 2005, HomePlug Inc PHY Encoding

Copyright © 2005, HomePlug Inc PHY Performance Test – 10 Homes  Typical PHY data rates –70-100Mbps  80% of outlet pairs –55 Mbps or better  95% of outlet pairs –35 Mbps or better  98% of outlet pairs –27 Mbps or better  ~90% MAC efficiency for HDTV

Copyright © 2005, HomePlug Inc MAC Highlights  Network managed by a Central Coordinator (CCo)  Three access methods within a network: –Beacon: Non-contention, CCo transmits Beacon in dedicated slot –CSMA: Contention-based, exchange of priority-based user data and management messages, shared with HP 1.0 –Contention-free: Only designated station transmits. QoS guarantee  Beacon Period is divided into “Regions” –Schedules specified in Beacons –Different allocations are further specified in some Regions  Beacon Period synchronous with AC line cycle  Allocations: persistent, or non-persistent (valid for current Beacon Period only)  Neighbor network coordination –Sharing channel with other AV networks (MDUs)

Copyright © 2005, HomePlug Inc MAC Encapsulation

Copyright © 2005, HomePlug Inc MPDU Bursting  Many PHY Blocks (or segments) are typically sent in a single MPDU –PHY blocks are individually Turbo FEC encoded –PHY Blocks are selectively acknowledged (SACK) –Provides efficient retry transmission over the noisy powerline medium  More than one MSDUs may be sent in a burst for efficiency

Copyright © 2005, HomePlug Inc Beacon Period  Beacon period synchronized to AC line cycle –Provides timing for synchronized channel adaptation different bit loading for different phases on the AC line cycle –Provides stable QoS for TDMA allocations

Copyright © 2005, HomePlug Inc Channel Adaptation  Receiver responsible for determining Tone Map intervals and up to 6 Tone Maps per transmitter –Stations exchange SOUND PPDUs so the receiver can determine optimal tone maps (e.g., modulation per tone, code rate and cyclic prefix length) –Stations continuously monitor data PPDUs (SNR estimate per carrier, PB error rate, etc.) to update tone maps –Different tone maps may be used in different intervals of the AC line cycle

Copyright © 2005, HomePlug Inc Central Coordinator  Beacons transmission –AC line cycle sync, network clock, & schedule  Association, authentication & security –Admit new stations into network  Admission control and bandwidth management –Determine schedules that meets QoS requirements –Persistent allocation provides coarse-scale allocation –Real-time adjustment made based on stations’ queue depth  Neighboring network coordination –Coordinate sharing of BW between neighbor CCos

Copyright © 2005, HomePlug Inc Quality of Service (QoS)  Connections –Parameter Based QoS (TDMA) –Priority Based QoS (CSMA)  Higher Layer Entities (HLEs) –Connection Specification (CSPEC) and Control –QoS Management and Control  Connection Manager (CM) –Stations exchange QoS requirements (CSPEC) and set up a connection –CSPEC contains min./avg./max. data rate, delay bound, etc. –If contention-free allocation is needed, stations then send BW request to CCo  CCo –Admission Control, Bandwidth Management and Scheduling  Convergence Layer (CL) –Packet classification based on CSPEC –Automatic connection service – create CSPEC –QoS Monitoring –Smoothing & Jitter Control

Copyright © 2005, HomePlug Inc Neighbor Networks  One Physical Network & Many Logical Networks  CCo maintains an Interfering Network List (INL): contains networks that it interferes –A network coordinates with networks in its INL (i.e., no chaining effect) to share the channel –CSMA Region is shared –TDMA Regions are reserved for each network in the ILN Reserved Regions may be reused by networks not in the ILN  Synchronization –CCo using the first Beacon Slot synchronizes to the AC line cycle; all other CCos synchronizes to it

Copyright © 2005, HomePlug Inc Security  Encryption is based on 128-bit AES in Cipher Block Chaining (CBC) mode  Data Protection (Privacy) –NEK: Payload encrypted with a rotating Network Encryption Key –Tone Maps  Authentication: Gaining Network Access – NMK: Network Membership Key defines a logical network and is used to distribute the NEK  Authorizing a New Station –Direct entry of NMK, requires a user interface –DAK: Encryption with Device Access Key –“Easy Connect” push button mechanism (less secure)  Supports HLE protocols such as 802.1x

Copyright © 2005, HomePlug Inc Summary HomePlug AV meets the market requirements for in-home networking –Physical Layer designed for robust, near capacity operation for the powerline channel –MAC layer provides near optimum use of the PHY –QoS guarantees are provided for video, audio and voice –AV Specification provides implementation flexibility for innovation –Experience and product maturity will bring further performance improvements  Additional information about HomePlug technologies is available on the HomePlug web site: –