Proposal for Downstream MPRS

January 2017

Glen Kramer, Broadcom Jean-Christophe Marion, TiBiT Communications Marek Hajduczenia, Charter Communications

Proposal for Downstream MPRS

1 IEEE P802.3ca Task Force meeting, Huntington Beach, CA

NGEPON Multi-Point Reconciliation Sublayer Upstream MPRS was reviewed over several meeting cycles Was accepted in San Antonio

– ONU state diagrams (see motion #4) • Input Process • Transmit Process

– OLT state diagrams (see motion #5) • Receive Process • Output Process

January 2017 IEEE P802.3ca Task Force meeting, Huntington Beach, CA 2

NGEPON Key MPRS Advantages

#1: MPRS provides a transparent bit transport mechanism.

MPRS takes bits from a transmitting MAC and delivers them in the same order and without modification or interpretation to the receiving MAC.

MPRS doesn’t care if MAC sends any data or just idles.

MPRS doesn’t care in what format the data arrives from the MAC.

MPRS does not care how large the frames are or how the frames are aligned to 25GMII lanes (/S/ can be at octet 0 or octet 4).



#2: No unwanted inter-layer dependencies

MPRS is self-contained. – Completely encapsulates and hides forming the envelopes,

envelope alignment, and skew recovery

MPRS eliminates the need for the MPCP to be in the data path. – In 10G_EPON, the MPCP is in the data path to check if next

data frame fits in the grant

MPRS eliminates the need for the MPCP to emulate the PHY. – In 10G-EPON, the MPCP emulates PHY to predict when the

channel becomes available and when the parity is inserted



#3: MPRS is direction-agnostic

At the last meeting, the MPRS state diagrams were accepted for the upstream direction.

There is nothing in these state diagrams that makes them upstream-only.


NGEPON Downstream MPRS Proposal Use the same state diagrams as defined for the upstream for the

downstream direction

Instead of defining 8 processes, we only need to define 4 (which we have done already)


(1) ONU Input Process Input Process (1)

(2) ONU Transmit Process (3) OLT Receive Process

Transmit Process (2) (4) OLT Output Process

(5) OLT Input Process Receive Process (3)

(6) OLT Transmit Process (7) ONU Receive Process

Output Process (4) (8) ONU Output Process

NGEPON MPRS is Symmetric


ONUOLT

Input Process

TXFIFO

Transmit Process

Transmit Process

Transmit Process

Transmit Process

Output Process

RXFIFO

Receive Process

Receive Process

Receive Process

Receive Process

Output Process

RXFIFO

Receive Process

Receive Process

Receive Process

Receive Process

Input Process

TXFIFO

Transmit Process

Transmit Process

Transmit Process

Transmit Process

NGEPON ONU Functional Map

Yellow boxes are done January 2017 IEEE P802.3ca Task Force meeting, Huntington Beach, CA 8

MAC Control Client

MPCP

PHY

and

Dat

a Li

nk L

ayer

s (in

sco

pe fo

r 802

.3ca

)

Shaping/Policing Scheduling

GATE Reception Process

Envelope Activation Process

Hig

her l

ayer

s (o

ut o

f sco

pe

for 8

02.3

ca)

REPORT Generation

Process

MAC:MA_CONTROL.request(REPORT)

MAC:MA_CONTROL.indication(GATE)

MPRS_CTRL.indication(…)

MPRS_CTRL.request(…)

MCC:MA_CONTROL.indication(grants[7])

MCC:MA_CONTROL.request(envelopes[N])

MAC:MA_DATA.request(…)MAC:MA_DATA.indication(…)

MPRS

MAC 1(ULID)

MAC 0(PLID)

MAC 2(ULID)

MAC 3(ULID)

Input Process

MAC 4(ULID)

PMD

MAC 5(ULID)

25 G

MII

(TX

)

PCS (TX)

PMA (TX)

Transmit Process

Receive Process

25 G

MII

(RX

)

PCS (RX)

PMA (RX)

25 G

MII

(TX

)

PCS (TX)

PMA (TX)

Transmit Process

25 G

MII

(TX

)PCS (TX)

PMA (TX)

Transmit Process

25 G

MII

(TX

)

PCS (TX)

PMA (TX)

Transmit Process

Receive Process

25 G

MII

(RX

)

PCS (RX)

PMA (RX)

Receive Process

25 G

MII

(RX

)

PCS (RX)

PMA (RX)

Receive Process

25 G

MII

(RX

)

PCS (RX)

PMA (RX)

Output Process

MAC 6(ULID)

MAC 7(ULID)

MAC 8(ULID)

MAC 9(ULID)

MAC 10(ULID)

MAC M(ULID)

Control Plane Data Plane

MAC Control

MAC & PHY

MAC Client

Reporting agent

TX BW allocation agent

(group expansion)Tx Queues

Rx Queues

MCC:MA_CONTROL.request(REPORT)

Classification

NGEPON OLT Functional Map

Yellow boxes are done – same as in ONU January 2017 IEEE P802.3ca Task Force meeting, Huntington Beach, CA 9

MAC Control Client

MPCP

PHY

and

Dat

a Li

nk L

ayer

s (in

sco

pe fo

r 802

.3ca

)

Shaping/Policing Scheduling

GATE Generation

Process

Envelope Activation Process

Hig

her l

ayer

s (o

ut o

f sco

pe

for 8

02.3

ca)

REPORT Reception Process

MAC:MA_CONTROL.indication(REPORT)

MAC:MA_CONTROL.request(GATE)

MPRS_CTRL.indication(…)

MPRS_CTRL.request(…)

MCC:MA_CONTROL.request(envelopes[N])

MAC:MA_DATA.request(…) MAC:MA_DATA.

indication(…)

MPRS

MAC 0(PLID)

MAC P(PLID)

MAC 1(ULID)

Input Process

MAC 2(ULID)

PMD

MAC 3(ULID)

25 G

MII

(TX

)

PCS (TX)

PMA (TX)

Transmit Process

Receive Process

25 G

MII

(RX

)

PCS (RX)

PMA (RX)

25 G

MII

(TX

)

PCS (TX)

PMA (TX)

Transmit Process

25 G

MII

(TX

)PCS (TX)

PMA (TX)

Transmit Process

25 G

MII

(TX

)

PCS (TX)

PMA (TX)

Transmit Process

Receive Process

25 G

MII

(RX

)

PCS (RX)

PMA (RX)

Receive Process

25 G

MII

(RX

)

PCS (RX)

PMA (RX)

Receive Process

25 G

MII

(RX

)

PCS (RX)

PMA (RX)

Output Process

MAC 4(ULID)

MAC 6(ULID)

MAC 7(ULID)

MAC 8(ULID)

MAC M(ULID)

Control Plane Data Plane

MAC Control

MAC & PHY

MAC Client

TX BW allocation

agentTx Queues

Rx Queues

MCC:MA_CONTROL.indication(REPORT)

ClassificationRX BW

allocation agent

MCC:MA_CONTROL.request(GATE)

MAC 5(ULID)

NGEPON Upstream vs. Downstream The difference between the upstream and downstream

directions is only in how the envelopes are scheduled. The envelope-scheduling decision is confined to the MAC Control Client (specifically, the TX BW allocation agent)

Input and output of TX BW Allocation Agent:


ONU OLT

Input Channel availability per LLID (received in the GATE message)

In case of group granting (GLID):

Preconfigured weights/QoS parameters

Queue state of different LLIDs

Channel availability per LLID (known via NMS)

Preconfigured weights/QoS parameters

Queue state of different LLIDs

(same as in the case of group granting at the ONU)

Output Set of envelope descriptors for individual LLIDs

Set of envelope descriptors for individual LLIDs

NGEPON OLT’s MAC Control Client MAC Control Client at the OLT has all the information

necessary to schedule downstream envelopes. – QoS associated with each LLID – Queue state of each LLID – Number of channels/wavelengths available to each ONU (may change

dynamically)

If many queues have a single frame waiting in them, the MAC Control Client will issue envelopes that match individual frame size, thus sending one frame per envelope.

If queues grow larger, the MAC Control Client may schedule larger envelopes that include multiple frames, or it may still decide to send one frame per envelope.

In all cases, since the MAC Control Client also has the visibility into the data queues, it can always schedule envelopes matching the frame boundaries, so that the ONUs do not need to have the reassembly buffers. January 2017 IEEE P802.3ca Task Force meeting, Huntington Beach, CA 11

NGEPON Conclusion MPRS is done!

– Upstream MPRS state diagrams are already defined

– Upstream MPRS state diagrams are also applicable to the downstream

• Nothing needs to be added • Nothing can be removed

Future MPRS refinements – If we need any, apply to both upstream and downstream

– Any increase in complexity should be carefully weighted against the expected benefits

MAC Control Client is outside the scope of 802.3. – Do we need to standardize the MAC Control Client anywhere else?


January 2017

(Contribution to .3ca draft)

Layer Diagrams and Interfaces


NGEPON Layering Diagram

100G-EPON layering diagram

Compare to 10G-EPON

January 2017

Higher Layers (OLT Control Plane)

Multi-Point Reconciliation Sublayer (MPRS)

MAC

PMD

MAC

Multi-Point MAC Control (MPMC)

OAM OAM

MDI

Higher Layers(OLT Data Plane)

Ethernet Layers

MAC Client MAC Client

MAC MAC


25 G

MII

PCS

PMA

25 G

MII

PCS

PMA

25 G

MII

PCS

PMA

25 G

MII

PCS

PMA

Higher Layers (ONU Control

Plane)

Multi-Point Reconciliation Sublayer (MPRS)

MAC

PMD

Multi-Point MAC Control

(MPMC)

OAM

MDI

Higher Layers(ONU Data Plane)

Ethernet Layers

MAC Client

MAC MAC


25 G

MII

PCS

PMA

25 G

MII

PCS

PMA

25 G

MII

PCS

PMA

25 G

MII

PCS

PMA

Optical distributor/combiner

Fiber

Fiber

PON Medium

Fibe

r

Fibe

r

Physical

Data Link

Network

Transport

Session

Presentation

Application

OSI Reference Model Layers

Physical

Data Link

Network

Transport

Session

Presentation

Application

OSI Reference Model Layers

PHY

PHY

OLT

ONU

NGEPON MPRS Interfaces

Compare to 10Gb/s P2P RS

Compare to 10/1G-EPON RS


Multi-Point Reconciliation

Sublayer (MPRS)

Figure 202-xx: Multi-Point Reconciliation Sublayer (MPRS) inputs and outputs

TXD[0]<31:0>TXC[0]<3:0>TX_CLK25

RXD[0]<31:0>RXC[0]<3:0>RX_CLK25[0]

25GMII[0]

TXD[1]<31:0>TXC[1]<3:0>TX_CLK25

RXD[1]<31:0>RXC[1]<3:0>RX_CLK25[1]

25GMII[1] a

TXD[2]<31:0>TXC[2]<3:0>TX_CLK25

RXD[2]<31:0>RXC[2]<3:0>RX_CLK25[2]

25GMII[2] b

TXD[3]<31:0>TXC[3]<3:0>TX_CLK25

RXD[3]<31:0>RXC[3]<3:0>RX_CLK25[3]

25GMII[3] b

PLS Service Primitives 25GMII Signals

PLS_DATA[0].request

PLS_SIGNAL[0].indication

PLS_DATA[0].indication

PLS_DATA_VALID[0].indication

PLS_CARRIER[0].indication

MAC[0]

PLS_DATA[1].request

PLS_SIGNAL[1].indication

PLS_DATA[1].indication

PLS_DATA_VALID[1].indication

PLS_CARRIER[1].indication

MAC[1]

PLS_DATA[M].request

PLS_SIGNAL[M].indication

PLS_DATA[M].indication

PLS_DATA_VALID[M].indication

PLS_CARRIER[M].indication

MAC[M]

a – Signals present only in 50G-EPON and 100G-EPON devicesb – Signals present only in 100G-EPON OLT devices

MPRS_CTRL[0].indicationMPRS_CTRL[0].request

MPRS_CTRL[1].indication aMPRS_CTRL[1].request a

MPRS_CTRL[2].indication bMPRS_CTRL[2].request b

MPRS_CTRL[3].indicationb

MPRS_CTRL[3].request b

MPRS Control Primitives

January 2017

Thank You


Documents

Proposal for Downstream MPRS