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Ichiro Satoh

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Match = strike.0def

VM = coin.coffee.VMdef

Clock = tick.Clockdef

Light = turnOn.turnoff.Light def

Ichiro Satoh

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VM = coin.(button1.coffee.VM + buton2.tea.VM)

tea

coffee

Ichiro Satoh

Example

CM = coin.coffee.CMdef

CS = coin.coffee.CSdef

CS | CM

Ichiro Satoh

ExampleCM CS

coin

coffeecoffee

coin

pubCM | CS

CS|CM|CS’

CM CS

coin

coffeecoffee

coin

pub

CS’

coin

coffee pub

Ichiro Satoh

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n u�·Àµ«¿

n r��(S)����(R)�u�²º¶¿(C)

S = send.ÃS’ | TÄS’ = dataS.start.(acks.S+timeout.S’)

T = start.timeout.T

C = dataS.(dataR.C+τ.C) + ackR.(ackS.C+τ.C)

R = dataR.ackR.receive.R

Ichiro Satoh

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Ichiro Satoh

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n u�·Àµ«¿

n r��(S)����(R)�u�²º¶¿(C)

S = send.S’S’ = dataS.start.(ackS.stop.S+timeout.S’)

T = start.(timeout.T+stop.T)

C = dataS.(dataR.C+τ.C) + ackR.(ackS.C+τ.C)

R = dataR.ackR.receive.R

Ichiro Satoh

0{

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S|T|C|R = send.S’ | start.(timeout.T+stop.T) |

dataS.(dataR.C+τ.C) + ackR.(ackS.C+τ.C) | dataR.ackR.receive.R

→ dataS.start.(ackS.stop.S+timeout.S’) | start.(timeout.T+stop.T) | dataS.(dataR.C+τ.C) + ackR.(ackS.C+τ.C) | dataR.ackR.receive.R (�A)

send

Ichiro Satoh

0{

→ start.(ackS.stop.S+timeout.S’) | start.(timeout.T+stop.T) | dataR.C+τ.C | dataR.ackR.receive.R

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | dataR.C+τ.C | dataR.ackR.receive.R

���0{��¤�¥ (�B)

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | C | ackR.receive.R

τ(dataS)

τ(start)

τ(dataR)

Ichiro Satoh

0{

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | dataS.(dataR.C+τ.C) + ackR.(ackS.C+τ.C) | ackR.receive.R

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | ackS.C+τ.C | receive.R

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | ackS.C+τ.C | R

���0{��¥ (�C)

→ stop.S+timeout.S’ | timeout.T+stop.T | C | R

→ S | T | C | R

τ(ackR)

receive

τ(ackS)

τ(stop)

Ichiro Satoh

0{

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | dataR.C+τ.C | dataR.ackR.receive.R

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | C | dataR.ackR.receive.R

→ S’ | T | C | dataR.ackR.receive.R

= dataS.start.(ackS.stop.S+timeout.S’) | start.(timeout.T+stop.T) | dataS.(dataR.C+τ.C) + ackR.(ackS.C+τ.C) | dataR.ackR.receive.R Ã�A�"�Ä

τ

τ(timeout)

(�B)

Ichiro Satoh

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | ackS.C+τ.C | R

���0{��¥

→ stop.S+timeout.S’ | timeout.T+stop.T | C | R→ S | T | C | R

���

→ ackS.stop.S+timeout.S’ | timeout.T+stop.T | C | R→ S’ | T | C | R

τ(ackS)

τ(send)

0{

τ

τ(timeout)

(�C)

Ichiro Satoh

Alternating Bit Protocol

Sender ReceiverTrans

Ack

send0send1

trans0trans1

reply0reply1

ack0ack1

accept deliver

Sender,Receiver�0,1�M:§ ��T<�£Q�¥M:���§���¥�M:§�p��¥

�DM: Sender=0, Receiver=1

t��u�n����I,¡fe���� ��7��¥u���_

Ichiro Satoh

ABP�jq(Sender,Receiver)

Ichiro Satoh

ABP�jq(Trans,Ack)

Ichiro Satoh

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