WashingtonWASHINGTON UNIVERSITY IN ST LOUIS

jdd@arl.wustl.edu

How to Implement theWaveVideo Pluginin an MSR Router

2WashingtonWASHINGTON UNIVERSITY IN ST LOUIS

John DeHart- 04/19/23 15:57

WaveVideo• Example of application specific congestion control

• Implemented as:– Video Encoder

– Router Plugin

– Video Decoder

• Current implementation is in the Crossbow framework

• Uses about 3 Mb/s for video

• Requires congestion to demonstrate its usefulness

3WashingtonWASHINGTON UNIVERSITY IN ST LOUIS

John DeHart- 04/19/23 15:57

Current WV Assumptions• It will be given some indication of:

– Its target rate in bits/second

– Does not actually use any indication of congestion being present

• Currently works with DRR– Sends a PCU message to the crossbow packet scheduler for

interface to get its target rate.

• If WV behaves, no one else will drop its packets.– WV plugin needs to be the only place where WV packets get

dropped

– Relies on DRR dropping packets from the longest queue• Each flow corresponds to a queue

• All flows share equally

• Therefore if WV stays under its share and there is congestion it will be because there is another longer queue

4WashingtonWASHINGTON UNIVERSITY IN ST LOUIS

John DeHart- 04/19/23 15:57

Ingress SPC, No FPX

interrupt

PCU Framework

Y.1X.1 Z.1

W.1

IP Options

X.2 Y.1Z.2

SW Interrupt Priority

HW Interrupt

AP

IC B

uff

er M

anag

emen

t In

sert

In

traP

ort

Sh

im(A

dd

In

pu

t V

IN)

...

SP1

SP2

SPN

AP

IC

Exa

ct M

atch

(a

dd

SID

)

Rou

te L

ook

up

(A

dd

Ou

tpu

t V

IN)

SID?IP opt?

Local ResourceManager (swint)

AP

IC

DQ

Out PN 0

Out PN 1

...

Out PN M

hi frequencyinterrupt (100us)

CP commands

CP commandprocessor

Command (AAL0) reply to CP

Rep

lace

In

traS

him

wit

h I

ntg

erS

him

In/Out (AAL0) DQ Broadcast Cells

Do we have any Packet Schedulingon Ingress Side?Will WV packetsbe dropped if thereis congestion?

5WashingtonWASHINGTON UNIVERSITY IN ST LOUIS

John DeHart- 04/19/23 15:57

Egress SPC, No FPX

interrupt

PCU Framework

Y.1X.1 Z.1

W.1

Manage

X.2 Y.1Z.2

SW Interrupt Priority

HW Interrupt

AP

IC B

uff

er M

anag

emen

t In

sert

In

traP

ort

Sh

im(A

dd

In

pu

t V

IN)

...

In P1

In P2

In PM

AP

IC

Exa

ct M

atch

(a

dd

SID

)

SID?

Local ResourceManager (swint)

CP commands

CP commandprocessor

Command (AAL0) reply to CP

Det

erm

ine

Ou

t V

C

Rem

ove

Sh

im

AP

IC

DQ

Out NH 0

Out NH 1

...

Out NH N

DRRService

drr threadhi frequency

interrupt (100us)

DQ Broadcast Cells

Is this Packet Schedulingon Egress Side per flow?If not, how can WV know that it behaving will make a difference?