parallel v. serial typically a uart byte ordersandbox.mc.edu/~bennet/cs423v2/slides5/conn-4.pdf ·...

Codin

gan

dC

onnec

ting

Ch.

9–12

.

CS 423 ·TWBennet

·

MississippiCollege

1

Para

llelv.

Seri

al

CS 423 ·TWBennet

·

MississippiCollege

2

Para

llelv.

Seri

al

Par

alle

lm

oves

mor

edat

aat

atim

e.

Par

alle

lbet

ter

mat

ches

inte

rnal

har

dw

are.

Typ

ically

aU

ART

Par

alle

lca

ble

sar

ela

rger

and

mor

eex

pen

sive

.

Inpra

ctice,

seri

alse

ems

most

use

dand

incr

easing.

CS 423 ·TWBennet

·MississippiCollege

3

Byte

Ord

er

Eth

ernet

stan

dar

d.

Sim

ilar

toor

der

use

dby

Inte

lC

PU

s.

CS 423 ·TWBennet

·

MississippiCollege

4

Bad

Tim

ing

CS 423 ·TWBennet

·

MississippiCollege

5

Synch

ronous

v.

Asy

nch

ronous

Kee

pin

gth

ese

nder

and

rece

iver

synch

roniz

ed.

Asy

nch

ronous

Dat

ase

nt

atra

ndom

inte

rval

s.

Extr

ale

adin

gbits

synch

roniz

efo

rth

attr

ansm

issi

on.

Usu

ally

each

byte

.

CS 423 ·TWBennet

·

MississippiCollege

6

RS

232

CS 423 ·TWBennet


7

Synch

ronous

Pro

duce

sa

const

ant

stre

amof

bits.

Just

send

zero

sif

ther

e’s

noth

ing

tosa

y.

Asy

nch

ronous

Synch

roniz

ation

Just

bec

ause

your

asynch

ronou

sdoes

n’t

mea

ncl

ock

sdon

’tdri

ft

USB

use

sN

RZ-I

with

no

chan

gefo

r1

Ext

raze

roafter

any

six

ones

toass

ure

atransition.

Eth

ernet

fram

esar

epre

ceded

by

apre

fix

ofon

es.

CS 423 ·TWBennet

·

MississippiCollege

8

Fra

min

g

Wra

pfr

ames

ofdat

ain

know

nse

quen

ce.

Thes

em

arke

rsre

-synch

roniz

eth

ere

ceiv

er’s

clock

.

Som

esp

ecia

lm

arke

rm

eanin

g“n

odat

a.”

CS 423 ·TWBennet

·

MississippiCollege

9

Isoch

ronous

Tra

nsp

ort

The

net

wor

ktr

ansp

orts

dat

aat

aco

nst

ant

rate

.

The

net

wor

km

ust

be

fed

dat

aat

exac

tly

that

rate

.N

odata

?Sen

dze

ro.

The

net

work

must

befed.

Des

igned

for

tran

smis

sion

ofau

dio

orvid

eost

ream

s.

Tra

nsitionalfo

rte

lephone

net

work

s.

CS 423 ·TWBennet

·

MississippiCollege

10

Dir

ection

Sim

ple

xO

ne

Way

Full-D

uple

xBoth

ways

all

the

tim

eTel

ephone

Hal

f-D

uple

xBoth

way

one

ata

tim

eW

alk

ie-T

alk

ie

CS 423 ·TWBennet


11

Carr

yin

gD

ata

Over

Sin

eW

aves

Sin

ew

aves

surv

ive

long

dis

tance

sbet

ter.

When

usi

ng

radio

,ce

rtai

nfr

equen

cies

pro

pag

ate

bet

ter.

Dat

ais

sent

by

modifyin

gth

eca

rrie

r.

CS 423 ·TWBennet

·

MississippiCollege

12

Modula

tion

Asi

nuso

idal

carr

ier

ism

odifi

ed(m

odula

ted)

under

contr

olof

adig

ital

sign

al.

The

dig

ital

sign

alca

nbe

reco

vere

dfr

omth

em

odula

ted

carr

ier

sign

al.

Modem

stan

ds

for

modula

tor-

dem

odula

tor.

Can

modula

te:

amplitu

de,

freq

uen

cy,or

phas

e.

The

carr

ier

freq

uen

cyis

the

chan

nel

ban

dw

idth

.

CS 423 ·TWBennet

·

MississippiCollege

13

Analo

gM

odula

tion

CS 423 ·TWBennet

·

MississippiCollege

14

Dig

italM

odula

tion

Am

plitu

de

Modula

tion

Am

plitu

de

Shift

Keyin

g

1 0

10

01

CS 423 ·TWBennet


15

Fre

quency

Modula

tion

Fre

quency

Shift

Keyin

g

1 0

10

01

1 0 CS 423 ·TWBennet

·

MississippiCollege

16

Bin

ary

Phase

Shift

Modula

tion

1 0

10

01

1 0 CS 423 ·TWBennet

·

MississippiCollege

17

Som

eP

racticalC

oncern

s

Aca

rrie

rca

nbe

modula

ted

with

anan

alog

ordig

ital

sourc

e.Phase

shiftra

rely

use

dwith

analo

g.

Pic

ture

ste

nd

toex

agge

rate

mag

nitude

ofth

ech

ange

.

Am

plitu

de

nee

ds

tost

ayla

rger

than

the

noi

sesi

gnal

.

Fre

quen

cyusu

ally

nee

ds

tost

ayin

side

ach

annel

.

CS 423 ·TWBennet

·

MississippiCollege

18

Quad

Phase

Shift

Modula

tion

1 01 0

01

11

00

01

Tw

obits

ata

tim

e.

CS 423 ·TWBennet


19

Const

ellation

Dia

gra

ms

Tw

oP

has

esFou

rP

has

es

CS 423 ·TWBennet

·

MississippiCollege

20

Com

bin

eA

mplitu

de

and

Phase

1 01 0

01

11

00

01

CS 423 ·TWBennet

·

MississippiCollege

21

Com

bin

eA

mplitu

de

and

Phase

CS 423 ·TWBennet

·

MississippiCollege

22

Quadra

ture

Am

plitu

de

Modula

tion

16-Q

AM

CS 423 ·TWBennet


23

Modem

s

Modem

=M

odula

tor/

Dem

odula

tor

Wir

e,ra

dio

,op

tica

l.

CS 423 ·TWBennet

·

MississippiCollege

24

Dia

lup

Dig

ital

tovo

ice

freq

uen

cySou

nd

sam

ple

dan

ddig

itiz

edby

the

phon

esy

stem

CS 423 ·TWBennet

·

MississippiCollege

25

Dia

lup

Dia

lup

has

abou

t24

00H

zban

dw

idth

.

One

bit

ata

tim

egi

ves

4800

bps

max

imum

rate

.

CS 423 ·TWBennet

·

MississippiCollege

26

We

Can

Do

Bett

er

V.3

2(3

2poi

nts

)V

.32b

is(1

28poi

nts

)

V.3

2bis

gets

14,4

00bps

CS 423 ·TWBennet


27

Multip

lexin

g

Sen

din

gm

ultip

lest

ream

sov

era

shar

edm

ediu

m.

CS 423 ·TWBennet

·

MississippiCollege

28

Types

ofM

ultip

lexin

g

Fre

quen

cyD

ivis

ion

Multip

lexin

gC

hannel

s

Wav

elen

gth

Div

isio

nM

ultip

lexin

gFD

Mfo

roptica

lfibe

r

Tim

eD

ivis

ion

Multip

lexin

gTake

turn

s

Code

Div

isio

nM

ultip

lexin

gM

ath

ematica

lco

mbi

nation

CS 423 ·TWBennet

·

MississippiCollege

29

Fre

quency

Div

isio

nM

ultip

lexin

g

Sig

nal

son

vari

ous

carr

iers

are

easi

lyco

mbin

ed.

Filte

rsfo

rea

chch

annel

(fre

quen

cyra

nge

)se

par

ate

itou

t.

Atu

ner

isa

singl

eadju

stabl

efilter

.

Eac

hch

annel

isa

vir

tual

connec

tion

.

CS 423 ·TWBennet

·

MississippiCollege

30

Pra

cticalM

att

ers

Chan

nel

shav

ea

par

ticu

lar

wid

th.

Filte

rsm

aynot

be

per

fect

.

Chan

nel

shav

ea

separ

atio

nA

void

sin

terf

eren

ce.

Guard

band

CS 423 ·TWBennet


31

For

Inst

ance

CS 423 ·TWBennet

·

MississippiCollege

32

Div

idin

ga

Channel

FD

Mca

nbe

use

dto

re-d

ivid

ea

chan

nel

.

Subc

hannel

s

Pro

vid

ead

ditio

nal

ban

dw

idth

.

Pro

vid

ere

dundan

cyfo

rer

ror

corr

ection

.Sen

dth

esa

me

data

on

multip

lesu

bchannel

sSee

whic

hone

work

sbe

st

CS 423 ·TWBennet

·

MississippiCollege

33

AM

ultip

lexed

ChannelM

ay

Be

Multip

lexed

CS 423 ·TWBennet

·

MississippiCollege

34

Wavele

ngth

Div

isio

nM

ultip

lexin

g(W

DM

)

Sam

eid

eaup

inligh

ts.

CS 423 ·TWBennet


35

Synch

ronous

TD

M

CS 423 ·TWBennet

·

MississippiCollege

36

Synch

ronous

TD

M

Use

dfo

rdig

ital

phon

eca

lls.

Fra

min

gch

annel

isad

ded

whic

hse

nds

one

bit

each

round.

Rec

eive

rsi

mply

mak

essu

reit

isse

ndin

gal

tern

atin

g1

and

0.

Kee

ps

clock

ssy

nch

roniz

ed.

CS 423 ·TWBennet

·

MississippiCollege

37

Fra

min

gC

hannel

CS 423 ·TWBennet

·

MississippiCollege

38

Synch

ronous

TD

M,Etc

.

Ofco

urs

e,T

DM

-multip

lexed

chan

nel

sm

aybe

multip

lexed

agai

n.

TD

Mor

other

wis

e.

Sta

tist

icalT

DM

Skip

blo

cks

when

sender

has

not

hin

gto

say.

Add

ablo

ckID

soth

ere

ceiv

erca

nre

const

ruct

.

Sav

etim

eunle

ssse

nder

sar

era

rely

sile

nt.

CS 423 ·TWBennet


39

Invers

eM

ultip

lexin

g

Cre

ates

ahig

her

-cap

acity

chan

nel

from

seve

ralof

low

erca

pac

ity.

CS 423 ·TWBennet

·

MississippiCollege

40

Code

Div

isio

nM

ultip

lexin

g

Sen

der

shav

eID

num

ber

sw

hic

hw

ere

pre

sent

with

1an

d-1

.

IDs

are

ort

hog

onal,

mea

nin

gth

eir

dot

pro

duct

isze

ro.

1010

1100

(1,−

1,1,−

1)·(1

,1,−

1,−

1)=

(1×

1)+

(−1×

1)+

(1×−

1)+

(−1×

−1)

=0

CS 423 ·TWBennet

·

MississippiCollege

41

Code

Div

isio

nM

ultip

lexin

g(c

ont)

Multip

ly(c

ross

pro

duct

)th

edat

aby

each

sender

code.

011

101

(1,−

1,1,−

1)×

(−1,

1,1)

=((−

1,1,−

1,1)

,(1

,−

1,1,−

1),(1

,−

1,1,−

1))

(1,1,−

1,−

1)×

(1,−

1,1)

=((

1,1,−

1,−

1),(−

1,−

1,1,

1),(1

,1,−

1,−

1))

CS 423 ·TWBennet

·

MississippiCollege

42

Code

Div

isio

nM

ultip

lexin

g(c

ont)

Add

the

two

pro

duct

sto

geth

er

-11

-11

1-1

1-1

1-1

1-1

11

-1-1

-1-1

11

11

-1-1

02

-20

0-2

20

20

0-2

Tra

nsm

itth

esu

mnum

ber

sas

com

bin

edsi

gnal

.

Should

allow

som

esc

aling.

CS 423 ·TWBennet


43

Code

Div

isio

nM

ultip

lexin

g(c

ont)

Multip

lyby

the

code

agai

n.

(1,−

1,1,−

1)·

(0,2,−

2,0)

,(0

,−

2,2,

0),

(2,0,

0,−

2)=

(0−

2−

2+

0),(0

+2

+2

+0)

,(2

+0

+0

+2)

=(−

4,4,

4)

011

Oth

erse

nder

code

shou

ldpro

duce

sim

ilar

resu

lts.

CS 423 ·TWBennet

·

MississippiCollege

44

Code

Div

isio

nM

ultip

lexin

g(c

ont)

Use

din

cell

phon

es

No

mor

eeffi

cien

tth

anT

DM

But

don

’thav

eto

wai

tfo

ryo

ur

turn

Red

uce

sdel

ay

CS 423 ·TWBennet

·

MississippiCollege

45

Connecting

Hom

es

and

Sm

all

Busi

ness

es

Dow

nst

ream

:To

the

cust

omer

Upst

ream

:Fro

mth

ecu

stom

er

Nar

row

ban

d:

up

to12

8K

bps

Dia

lup

Lea

sed

circ

uit

mod

ems

Fra

ctio

nalT

1

Bro

adban

d:

hig

her

,but

the

bou

ndar

yis

uncl

ear

DSL

Cabl

eM

odem

sW

irel

ess

T1

and

hig

her

CS 423 ·TWBennet

·

MississippiCollege

46

Dig

italSubsc

riber

Lin

e

DSL

vari

etie

s

AD

SL:A

sym

met

ric;

for

residen

ces

AD

SL2:

Fast

erve

rsio

nSD

SL:Sym

met

ric;

for

busines

ses

with

serv

ers

HD

SL:Fast

erve

rsio

n,fo

rcl

ose

-by

busines

ses

VD

SL:Ver

y-hig

hbi

tra

te;pro

pose

d

CS 423 ·TWBennet


47

AD

SL

Hig

hdat

ara

tes

tohom

e.M

ax:

Downlo

ad

6.1

44

Mbp

s,640K

bps

uplo

ad.

Asy

mm

etri

cre

fers

tofa

ctth

eth

euplo

adan

ddow

nlo

adra

tes

diff

er

Oper

ates

over

stan

dar

dtw

iste

dpai

r.

Does

not

inte

rfer

ew

ith

ordin

ary

calls.

CS 423 ·TWBennet

·

MississippiCollege

48

AD

SL

Fre

quencie

s

Use

sfr

equen

cies

abov

eth

eau

dio

chan

nel

.

Diff

eren

tlines

suppor

tdiff

eren

tfr

equen

cies

.in

terf

eren

cege

om

etri

es

AD

SL

isad

aptive

–ch

oos

esfr

equen

cies

that

wor

k.

Discr

ete

Multi-Tone

Mod

ula

tion

(DM

T)

CS 423 ·TWBennet

·

MississippiCollege

49

DM

T

286

freq

uen

cies

(subch

annel

s)255

downlo

ad,31

uplo

ad.

4.13

25K

Hz

inte

rval

s,ab

ove

26K

wel

labo

ve4

KH

zca

lls

Ends

pro

be

each

avai

lable

freq

uen

cies

tose

ew

hat

wor

ks.

Noi

sysu

bch

annel

sar

em

odula

ted

less

den

sely

.

Act

ual

spee

ddep

ends

onhow

man

ych

annel

sca

nbe

use

dan

dhow

wel

l.

CS 423 ·TWBennet

·

MississippiCollege

50

AD

SL

Speeds

Spee

ds

dep

end

online

conditio

ns.

Up:

32–6

40K

bps

Dow

n:

32K

bps–

8.44

8Mbps

Asp

litt

erse

par

ates

the

phon

efr

equen

cies

for

extr

apro

tect

ion

CS 423 ·TWBennet


51

Cable

Modem

s

Dow

nlo

ad

Fre

quen

cym

ultip

lexin

g:C

han

nel

sas

sign

edto

anei

ghbor

hood.

Tim

em

ultip

lexin

gw

ithin

the

freq

uen

cy:

Rec

eive

rsge

tal

l—

dis

card

mes

sage

sdes

tined

else

wher

e.

Uplo

ad

Nei

ghbor

hoods

shar

eon

e6

MH

zch

annel

by

tim

em

ultip

lexin

g.D

ata

rela

yed

from

ther

eov

erfiber

.

Som

eea

rly

syst

ems

requ

ired

adia

lup

connec

tion

for

uplo

ad.

CS 423 ·TWBennet

·

MississippiCollege

52

Hybri

dFib

er

Coax

Cab

leT

Vis

one-

way

.

The

box

and

fiber

retu

rnlink

are

added

topro

vid

enet

wor

kin

gse

rvic

e.

CS 423 ·TWBennet

·

MississippiCollege

53

Cable

Fre

quencie

s

5to

50M

Hz

for

uplo

ad.

50to

450

MH

zuse

dfo

rT

V.

6M

Hz

per

channel

.

450

MH

zto

750

MH

zfo

rdow

nlo

ad.

CS 423 ·TWBennet

·

MississippiCollege

54

Speed

Up:

512

Kbps

Dow

n:

52M

bps

Gen

eral

lysh

ared

bet

wee

nso

me

grou

ps

ofcu

stom

ers.

Act

ual

spee

ddep

ends

onhow

man

yof

thos

ear

eac

tive

and

what

they

’re

doi

ng.

CS 423 ·TWBennet


55

More

Fib

er

FT

TC

:Fib

erto

the

curb

.P

rovid

eex

tra

serv

ices

,su

cha

tele

phon

e.

FT

TB

:Fib

erto

the

buildin

g.Fas

ter

uplo

adfo

rbusi

nes

ses.

FT

TH

:Fib

erto

the

hom

e.D

eliv

erex

tra

dat

a,su

chas

mor

een

tert

ainm

ent

chan

nel

s.

FT

TP

:Fib

erto

the

pre

mis

es.

Either

ofla

sttw

o.

CS 423 ·TWBennet

·

MississippiCollege

56

CM

TS

Cab

leM

odem

Ter

min

atio

nSyst

em.

Hea

d-E

nd

Modem

:A

tth

eca

ble

co.

Tai

l-E

nd

Modem

:A

tth

esu

bsc

riber

.A

bank

ofhea

d-e

nds

atth

eca

ble

offi

ce.

Tai

l-en

ds

com

munic

ate

with

hea

d-e

nd.

Tai

l-en

ds

do

notco

mm

unic

ate

with

each

other

.

CS 423 ·TWBennet

·

MississippiCollege

57

DO

CSIS

Dat

aO

ver

Cab

leSer

vic

eIn

terf

ace

Spec

ifica

tion

.

Spec

ifies

the

dat

afo

rmat

over

the

cable

.O

pen

indust

ryst

andar

d.

CS 423 ·TWBennet

·

MississippiCollege

58

Bro

adcast

Sate

llite

Bro

adca

stw

ith

stat

ion

addre

sses

,LA

Nst

yle

.

Ori

ginal

ly,uplo

adby

phon

e.

Now

,uplo

ads

thro

ugh

the

sate

llite.

CS 423 ·TWBennet


59

Wir

ele

ssB

roadband

Serv

ices

3G

cell

phone

serv

ices

Dat

atr

ansf

erre

dth

rough

the

cell

phon

enet

wor

k

WiM

AX

IEE

E80

2.16

Oper

ates

atfr

equen

cies

sim

ilar

toW

iFi

Sig

nal

sar

edir

ection

alSubsc

riber

units

must

be

aim

edco

rrec

tly.

Req

uir

esm

ultip

lebas

est

atio

ns

CS 423 ·TWBennet

·

MississippiCollege

60

Serv

ices

toP

rovid

ers

Acc

ess

tech

nol

ogie

sso

lve

the

last

mile

pro

blem

.

ISP

san

dla

rge

busi

nes

ses

nee

dhig

her

-cap

acity

connec

tion

s.co

rete

chnolo

gies

Thes

ear

eof

ten

leas

edfr

omte

lephon

eco

mpan

ies.

CS 423 ·TWBennet

·

MississippiCollege

61

DSU

/C

SU

Adap

tste

lephon

est

andar

ds

toco

mpute

rst

andar

ds.

CSU

talk

sto

the

phone

side.

DSU

talk

sto

the

com

pute

rside.

NIU

isth

eed

geofphone-

com

pany-

owned

equip

men

t.

CS 423 ·TWBennet

·

MississippiCollege

62

Data

Rate

s

Sta

ndard

circ

uits

0.06

4M

bps

is80

008-

bit

sam

ple

sper

seco

nd.

CS 423 ·TWBennet


63

T1

Data

Rate

s

T1

is1.

544

Mbps.

24ca

lls

is0.

064×

24=

1.53

6M

bps

The

extr

a0.

008

isco

ntr

olov

erhea

d.

Ther

eis

also

am

inim

um

rate

atw

hic

hyo

udat

am

ust

conta

in1’

s.

You

gener

ally

cannot

get

1.54

4M

bps.

Can

alw

ays

get

1.34

4M

bps;

may

be

bet

ter.

Man

yodd

com

plica

tion

s.

CS 423 ·TWBennet

·

MississippiCollege

64

More

Speed

OC

=O

ptica

lC

arr

ier

Suffi

xofC

mea

ns

no

inve

rse

multip

lexi

ng.

CS 423 ·TWBennet

·

MississippiCollege

65

SO

NET

Ast

andar

dfo

rfr

ames

over

ST

Sci

rcuits.

All

fram

es

are

the

sam

esi

ze.

Fra

me

size

dep

ends

online

spee

d.

8000

sam

ple

s/se

cis

125µ-s

ec/s

ample

.

Eac

hfr

ame

take

s12

5µ-s

ecto

tran

smit.

OC

-1:

51.8

40M

bps×

125

µ-s

ec=

6480

bits

=81

0byte

sO

C-3

:15

5.52

0M

bps×

125

µ-s

ec=

1944

0bits

=24

30byte

s

Sim

plifies

synch

ronou

sm

ultip

lexin

g.

CS 423 ·TWBennet

·

MississippiCollege

66

Sourc

es

Com

er,C

om

pute

rN

etwork

sand

Inte

rnet

s(O

ur

belo

ved

text

book.

)

http://www.faculty.iu-bremen.de/birk/lectures/PC101-

2003/14usb/FINAL%20VERSION/usb_protocol.html

http://www2.rad.com/networks/2000/usb/maintxt.htm-

#Physical_Layer

htt

p:/

/ww

w.tec

hfe

st.c

om/n

etw

orkin

g/w

an/t

1.htm

htt

p:/

/sea

rchnet

wor

kin

g.te

chta

rget

.com

/sD

efinitio

n/-

0,,s

id7

gci5

4841

8,00

.htm

l

Wik

iped

iaW

iMA

Xar

ticl

e

CS 423 ·TWBennet


67

parallel v. serial typically a uart byte ordersandbox.mc.edu/~bennet/cs423v2/slides5/conn-4.pdf ·...

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