Residential Ethernet Overview

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Residential Ethernet Overview

• Michael Johas Teener
• Plumblinks
• mike_at_plumblinks.com

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Digital Home Media Distribution
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What is the problem in Home CE Network?

• The lack of standard interface that is all things
  to all people
• Firewire/1394 has limited reach (1394c does but
  has other issues).
• Ethernet and Ethernet Switches does not support
  isochronous connections
• Without standard, CE devices needs more
  connectors, not fewer.
• The next generation contents are all digital and
  DRM-enabled.
• ISP needs compatible service class mapping to
  home
• Broadband delivery of the digital contents over
  Cable, xDSL, Satellite, needs an interface that
  guarantees the quality of experience.

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What are the residential challenges?

• Wiring distribution Medium
• Existing Wiring Wireless
• Phone (old and Cat 5), Coax (CATV), Powerline,
  Wireless
• HomePNA Ethernet , MoCA, HomePlug, WiFi UWB
• Regional Differences - Asia, North America,
  Europe
• Cost zero incremental cost over time
• Reduce the of connector types, leverage volume
• Configuration Ease no new configuration.
• uPnP, intelligent defaults, transparent (to the
  user) DRM.

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What are the possible solutions?

• Wired
• Ethernet FE and GE Works, but if there are no
  other traffic and over-provisioned.
• Residential Ethernet add isochronous support so
  that it works.
• Firewire/1394a works, but limited reach. 1394c
  requires GigE PHYs
• USB Master/Slave peripheral connection, short
  reach. Not fit for multi-point.
• MoCA proprietary protocol over RG59 coax
  medium-high cost.
• HomePlug proprietary protocol over power line
  high cost
• Wireless
• 802.11a/b/g 802.11e makes it work. Not ready
  for multiple HD contents.
• 802.11n Sufficient bandwidth, longer reach.
  Best solution for wireless.
• UWB Suffers from short reach (see 1394/USB).
  wireless 1394/USB

Best of the class solutions. The rest are
supplementary technologies
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Why Residential Ethernet?

• Ethernet is already the grand unifier in all
  other technologies
• WiFi, HomePlug, MoCA, HomePNA, all terminate to
  an Ethernet port.
• High-end media devices already has Ethernet.
• Enable these Ethernet interfaces with synchronous
  service class
• Wired Wireless solution required.
• Reliable guaranteed services are only available
  over wire.
• All wireless benefits and suffers from coverage
• 802.11n increases range by 2X or more, but
• Its bandwidth affected by interferences (other
  wireless the neighbors)
• Residential Ethernet MAC, once done, provides all
  future Ethernet interface with isochronous
  services.
• Ethernet Volume
• Power over Ethernet Option
• Ethernet Roadmap (10/100/1000/10G, PoE Plus, MAC
  Security, etc.)
• But Cat 5 is not installed in every home.
• Residential Ethernet is adoptable to other medium
  (at higher cost).
• Good reason that the solution must include
  wireless option.
• Much of Asia and new homes in N America do have
  Cat 5.

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What are CE Technical Challenges?

• Audio-Video Sync to multiple devices
• Low-latency for interactive
• Low Cost
• Plug Play
• really!

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Residential Ethernet Technical Overview

• Michael Johas TeenerPlumblinks
• mike_at_plumblinks.com

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Technical Challenges and Solutions

• Bounded Jitter (multi-room Video/Audio sync)
• End-point synchronization
• Bounded Latency (real-time apps).
• Interactive Voice and Video over IP
• Audio JAM session
• Control/Mgmt (channel/volume selection)
• Guaranteed session bandwidth
• QoS/CoS, over-provisioned BW does NOT do this.
• IEEE 1394 mechanisms work well and adoptable to
  Res Ethernet.

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IEEE 802.3 Residential Ethernet Study Group Status

• Call for Interest in July 2004
• Overwhelming support for Residential Ethernet
  Work
• Interest vote result 30 companies 80
  individuals
• Held two meetings, September and November.
• Next meeting in January 2004, the week of 23rd.
• Study Group Charter is to justify new standard
  not writing the standard, but
• Two workable proposals on the table
• Both would meet the requirements
• Both are compatible with IEEE 1394 (Firewire)
  services.
• One leverages from commodity Ethernet switches
• Link http//www.ieee802.org/3/re_study

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Proposal 1 Spyder LAN

• Introduces real-time data distribution function
  overlay in Ethernet Switches
• Looks more like Ethernet Repeater than Switch
• TDM service similar to IEEE1394 and IEEE 802.3af
  EFMs EPON
• Synchronous traffic serviced via network
  admission control.

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Proposal 2 Modified Ethernet Switch

• Introduces real-time traffic queue in Ethernet
  Switch
• Adds time-sync aware scheduler in addition to
  CoS/QoS aware scheduler.
• Backward compatible to any installed Ethernet
  Switch
• Small cost adder to Ethernet Switch.
• Only solution that offers commodity silicon and
  adoption upon introduction.

Simplified Ethernet Switch Block Diagram
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Common Solutions

• Clock Synchronization
• Adopt 802.1D STP-like master selection (based on
  MAC Device Class)
• 8 KHz clock sync, and 64 bit resolution (like
  1394)
• Link PnP
• Adopt 802.3 auto-negotiation. Need to add ResE
  to the selection code.
• Device PnP
• Adopt 802.1ab LLDP protocol (MAC/Link Discovery
  Protocol) as is.
• Synchronous Control Protocol
• Adopt 802.1 GARP (Generic Attribute Registration
  widely used for VLAN registration in form of
  GVRP)
• Path BW reservation
• Multicast/Broadcast group and path control could
  use GMRP as is.
• Very few new protocols need to be invented!

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Res Ethernet End-Point Model

• Choose the most compatible interface model to
  existing drivers.
• Sensible to support both models to minimize time
  to market.

Unified Res Ethernet Driver
Synchronous Driver e.g. ResE, 1394
Ethernet Driver
ResE support above the MAC
ResE support at the MAC
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Call for Action

• Residential Ethernet is a study group, and will
  to transition to a task force soon
• Your participation is appreciated
• Will require updates to 802 architecture
• 802.1D updates for isochronous routing/admission
  control
• Best if updates are useful for 802.11 and 802.15
  as well
• Want to allow all QoS capabilities preserved as
  data moves through Ethernet backbone!
• Need to start working on harmonization ASAP!

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Backup Slides

• Many slides and content lifted from Residential
  Ethernet Study GroupPresentations

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Clock Synchronization
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Bursting causes jitter
rx01 kHz
rx11 kHz
rx21 kHz
rx38 kHz
tx4
time
delay
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Bunching causes jitter
rx0
time
rx1
time
rx2
time
rx3
time
tx4
time
delay
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Bridge re-clocking bounds jitter
bridge
receive
cycle-stamp
(etc.)
cycleCount
isochronous
high

gate
transmit
asynchronous
low

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Synchronized reception/presentation
clockB
clockC
clockA
No long-term drift clockA, clockB, clockCClock
jitter sub nanosecond (after PLL)
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Synchronization services for client

• Clock synchronization direction control
• From/to network
• Clock to network
• Clock from network
• Higher level scheduling of services
• Need to know current time to know when in the
  future an event can be scheduled
• Time stamping of streaming data

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Synchronization in bridge

• Protocol to select master clock in network
• if no bridge, just uses highest MAC address
• Accept clock from port connected to network
  master
• Forward clock to other ports
• Re-use 802.1 STP precedence to select clock
  source.

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Admission Control
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Admission controls for client

• Request channel number
• Multicast address to use as DA
• Release channel number
• Request bandwidth from path to talker
• Bytes/cycle makes reservation in output queue
  of talker (and all output queues in path from
  talker)
• Talker address is channel (multicast address)
• Release bandwidth from path to talker
• Accept bandwidth request from listener
• Bytes/cycle makes reservation in output queue
  of self, if no resources, tags request
• Respond to bandwidth request from listener
• Sent to listener that made request
• Accept bandwidth response from talker
• Release local bandwidth reservation

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Admission controls in bridge

• Allocate channel using GMRP
• Forward bandwidth requests to talker if first
  request
• respond directly without forwarding if already
  routing channel
• Forward bandwidth responses to listener

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Isochronous transport

• Request transmit of isochronous packet
• DA, SA, data, cycle n
• Receive isochronous packet
• DA, SA, data, cycle n

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Clock Synchronization
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Adjacent-station synchronization
Timing snapshots
Station B
Station A
local
local
offset
offset
(t1)
(t3)
add
add
global
global
(t4)
(t2)
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Adjacent-station synchronization
Snapshot value distribution
Station B
Station A
local
local
offset
offset
(t1, t4-t2)
(t1)
(t3)
add
add
(t2, t3-t1)
global
global
(t4)
(t2)
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Adjacent-station synchronization
Offset value adjustments
Station B
Station A
local
local
offset
offset
(t1, t4-t2)
(t1)
(t3)
add
add
(t2, t3-t1)
global
global
(t4)
(t2)

• clockDelta ((t3 t1) (t4 t2)) / 2
• cableDelay ((t3 t1) (t4 t2)) / 2
• offsetB offsetA clockDelta

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Adjacent station synchronization
Station B
Station A
local
local
offset
offset
add
add
8 kHz
global
global