EE- 6607 and/6607/ http: //w w w . csc. gatech. edu/~copel Pr - - PowerPoint PPT Presentation

ee 6607
SMART_READER_LITE
LIVE PREVIEW

EE- 6607 and/6607/ http: //w w w . csc. gatech. edu/~copel Pr - - PowerPoint PPT Presentation

EE- 6607 and/6607/ http: //w w w . csc. gatech. edu/~copel Pr of . John A . Copel and j ohn. copel and@ ece. gatech. edu 404 894- 5177 O f f i ce: GCA TT Bl dg 579 em ai l or cal l f or of f i ce vi si t,


slide-1
SLIDE 1

EE- 6607

http: //w w w . csc. gatech. edu/~copel and/6607/

Pr

  • f

. John A . Copel and j

  • hn.

copel and@ ece. gatech. edu 404 894- 5177

O f f i ce: GCA TT Bl dg 579 em ai l

  • r

cal l f

  • r
  • f

f i ce vi si t,

  • r

cal l Kathy Cheek, 404 894- 9496

  • Netw or

k Sof tw ar e

EE6607. 02

Chap. 1, pp 16- 44 Text: Com puter N etw or ks, 3r d Edi ti

  • n

by A ndr ew S. Tanenbaum

slide-2
SLIDE 2

OSI Ref erence M odel

Fr

  • m

1977 to 1983 the I nter nati

  • nal

Standar di zati

  • n

O r gani zati

  • n

(I SO ) devel

  • ped

a ar chi tectur al m odel that separ ated com puter com m uni cati

  • n

pr

  • tocol

f uncti

  • ns

i nto l ayer s. Thi s system i s know n as the O pen System s I nter connecti

  • n

(O SI ) Ref er ence M odel (I SO Standar d 7498). Thi s m odel i s al so know n as the "seven- l ayer " m odel . These l ayer s take

  • utgoi

ng data f r

  • m

the l evel above, per f

  • r

m cer tai n f uncti

  • ns
  • n

i t, then pass the pr

  • cessed

data dow n to the l ayer bel

  • w .

They al so take r ecei ved data f r

  • m

the l ayer bel

  • w ,

per f

  • r

m (undo) the sam e f uncti

  • ns,

and pass the pr

  • cessed

data up to the l ayer above.

slide-3
SLIDE 3

The Seven O SI Layer s 7. A ppl i cati

  • n

Layer 6. Pr esentati

  • n

Layer 5. Sessi

  • n

Layer 4. Tr anspor t Layer 3. Netw or k Layer 2. Data Li nk Layer 1. Physi cal Layer

M em m oni c: A PeS Tr anspor t N etw or k Data Physi cal l y.

M anage- m ent Pl ane

slide-4
SLIDE 4

Dat a Encapsulat ion

Appl i cati

  • n

Layer Tr anspor t Layer Netw or k Layer Data Li nk Layer Physi cal Layer

AH Dat a TH AH Dat a NH TH AH Dat a DH NH TH AH Dat a Bit s over Physical M edium Dat a Dat a

Appl i cati

  • n

Layer Tr anspor t Layer Netw or k Layer Data Li nk Layer Physi cal Layer

slide-5
SLIDE 5

Application Layer Presenta- tion Layer Session Layer Transport Layer Netw ork Layer 802 Data Link Layer 802 Phys. Layer

Logi cal Li nk Contr

  • l

(LLC) M edi a Access Contr

  • l

(M AC) Physi cal Layer

Process

I nt ernet (I P) Net w ork I nt erf ace Transport (TCP & UDP)

Application Process

TCP/ I P has f our concept ional layers I SO 7- Layer M odel I EEE 802 Layers Telnet , FTP, SM TP

1 2 3 4 5

slide-6
SLIDE 6

TCP/ I P - t he Prot ocol of t he I nt ernet While t he I nt ernet Prot ocol Suit e is generally know n as TCP/ I P, t here are a number of prot ocols at dif f erent layers t hat make t he I nt ernet w ork.

I nt ernet Prot ocol

User Dat agram Prot ocol (UDP) Transmission Cont rol Prot ocol (TCP) Simple M ail Transf er (SM TP) Telnet (Terminal) File Transf er Prot ocol (FTP) Hyper- Text Transf er Prot ocol (HTTP)

Program (e.g., Brow ser)

slide-7
SLIDE 7

Pr

  • tocol

Layer Desi gn I ssues Data Di r ecti

  • ns
  • Si

m pl ex

  • ne

w ay

  • nl

y (f i r e al ar m )

  • Hal

f Dupl ex

  • ne

w ay at a ti m e (CB r adi

  • )
  • Dupl

ex

  • Both

w ays at

  • nce

(tel ephone)

Er r

  • r

Contr

  • l

(Detecti

  • n)
  • Retr

ansm i ssi

  • n

(A CK, NA K, ti m e-

  • ut)
  • For

w ar d er r

  • r

cor r ecti

  • n

Sequenci ng (SA R: Segm ent & Reassem bl e) M ul ti pl exi ng (m ul ti pl e sessi

  • ns,

1 ci r cui t) Rever se M ul ti pl exi ng

(1 sessi

  • n,

m ul ti

  • ci

r cui ts)

slide-8
SLIDE 8

Service Access Point s I CI + SDU I DU LAYER N LAYER N+1 SAP I CI SDU Node X Node Y PDU Header + SDU

I nt erf ace Dat a Unit I nt erf ace Cont rol I nf o Service Dat a Unit Prot ocol Dat a Unit

SDU

slide-9
SLIDE 9

Connecti

  • n

O r i ented Ser vi ce

  • Li

ke Tel ephone System

  • Packets

ar r i ve i n

  • r

der

Connecti

  • nl

ess Ser vi ce

  • Li

ke Post O f f i ce w i th m ul ti pl e l etter s

  • Packets

can be

  • ut
  • f

sequence

  • V ar

i abl e del ay

Q ual i ty

  • f

Ser vi ce

  • Rel

i abl e

  • never

l

  • ses

data (A CKed)

  • Unr

el i abl e

  • m ay

l

  • se

data

slide-10
SLIDE 10

Service Primit ives

M essages Bet w een Layers

LAYER N Service Provider LAYER N+1 Service User Node X Request Response Conf irm I ndicat ion Node Y Node X

slide-11
SLIDE 11

Layer

A ppl i cati

  • n:

Ser vi ce A dver ti si ng Pr

  • tocol

, Fi l e Ser ver Tr anspor t: NCP (f i l es) SPX (Lotus Notes) Netw or k: I PX Datal i nk: Ether net Token Ri ng A RCnet Physi cal : Ether net Token Ri ng A RCnet

Novel l Netw ar e

slide-12
SLIDE 12

Layer

A ppl i cati

  • n:

M ai l , Ter m i nal (Tel net), W eb, Fi l e Tr ansf er (FTP) Tr anspor t: TCP (r el i abl e) UDP (datagr am ) Netw or k: I P (I nter net Pr

  • tocol

) Datal i nk: Ether net, Token Ri ng, FDDI , DO CSI S (CA TV ), A TM , . . . Physi cal : Ether net, Token Ri ng, FDDI , DO CSI S (CA TV ), A TM , . . .

I nter net (TCP/I P)

slide-13
SLIDE 13

A RPA net

  • by

A dvanced Resear ch Pr

  • j

ects A gency

  • 1960'

s, used I nter f ace M essage Pr

  • cessor

s

  • Bui

l t by BBN, har d to connect to

  • ther

netw or ks

  • 1980'

s

  • Dom ai

n Nam i ng System (DNS) devel

  • ped

NSFnet

  • Desi

gned f

  • r

uni ver si ty r esear ch gr

  • ups

(1984)

  • NSF

f unded backbone and r egi

  • nal

netw or ks

  • A NS

(I BM , M CI et al ) com m er ci al i zed i n 1994, sol d to A m er i ca O nl i ne i n 1995.

  • NREN

(3 Gbps netw or k) author i zed by Congr ess i n 1991

  • NSF

f unded NA P' s i n San Fr an. , NYC, Chi cago, W ash. DC

  • I

nter net

  • m any

m or e . com ' s than . edu' s, . gov' s today. Based

  • n

TCP/I P Pr

  • tocol

s, def i ned by RFC.

slide-14
SLIDE 14

At lant a M ap of t he I nt ernet - Primary and Secondary Backbone Rout es

slide-15
SLIDE 15

Gi gabi t Testbeds (1996)

  • A ur
  • r

a

  • M I

T, U. Penn. , W atson, Bel l cor e

  • Bl

anca

  • A T& T

Bel l Labs, Ber kel ey, U. W i sconsi n

  • CA SA
  • Los

A l am os, Cal Tech, JPL, San Di ego S. C.

  • Nectar
  • M A N

f r

  • m

Pi ttsbur gh SC to CM U

  • V I

STA net

  • UNC,

NCSU, M CNC (Res. Tr i angl e Par k)

  • m ost

used 622 M bps (gover nm ent Gi gabi t)

l l cl

  • sed

now , except:

  • vBNS
  • V er

y hi gh- speed Backbone Netw or k (622M bps)

slide-16
SLIDE 16

Com m er ci al Data Com m uni cati

  • n

Ser vi ces X. 25

  • pl

us X. 3, X. 28, & X. 29 f

  • r

dum b ter m i nal s

  • vi

r tual ci r cui ts

  • ver

56 kbps l i nes

Fr am e Rel ay

  • ski

ps er r

  • r

checki ng at i nter m edi ate nodes

  • connecti
  • n-
  • r

i ented (vi r tual l eased l i nes)

SM DS

  • Sw i

tched M ul ti m egabi t Data Ser vi ce

  • Packet

ser vi ce, connecti

  • nl

ess, LA N i nter connects

  • Usual

l y DS- 3 (45 M bps)

I SO NET

  • Constant

bi t- r ate, channel i zed

  • r

not

I SDN

  • BRI

(2x64 kbps di al up) & PRI (24x64kbps)

B- I SDN

  • A TM

sw i tches and SO NET

slide-17
SLIDE 17

Standar ds O r gani zati

  • ns

I TU

  • I

nter nati

  • nal

Tel ecom m uni cati

  • ns

Uni

  • n
  • W or

l dw i de (CCI TT unti l 1993 nam e change)

I SO

  • I

nter nati

  • nal

Standar ds O r gani zati

  • n
  • O SI

(O pen System s I nter connect) M odel

I A B

  • I

nter net A r chi tectur e (A cti vi ti es) Boar d

  • set

up by DO D i n 1060' s

  • has

I ETF

  • I

nter net Engi neer i ng Task For ce

  • gener

ates RFC' s

  • r

equests f

  • r

com m ents.

  • >70

w or ki ng com m i ttees

I nter net Soci ety

  • i

nter est gr

  • up

cr eated, Tr ustees now appoi nt I A B m em ber s.

U. S.

  • NI

ST (gov), ANSI (i ndust r y), I EEE (pr

  • f

essi

  • nal

)