7
Page 1 1 EE122, Fall ‘05 EECS 122: Introduction to Computer Networks Course Goals and Overview Computer Science Division Department of Electrical Engineering and Computer Sciences University of California, Berkeley Berkeley, CA 94720-1776 2 EE122, Fall ‘05 Instructors Instructor: Ion Stoica ([email protected] ) - Office Hours: W 2-3 PM, 645 Soda Hall Textbooks - L. L. Peterson and B. Davie, Computer Networks: A System Approach, 3 nd Edition, Morgan Kaufman, San Francisco, 2003. - W. R. Stevens, B. Fenner, A. M. Rudoff, Unix Network Programming: The Sockets Networking API, Vol. 1, 3 rd Ed., Addison-Wesley, Boston, 2004. 3 EE122, Fall ‘05 TAs Jana Van Gruenen ([email protected] ) - Discussion section: Th 11-12 299 Cory Rowena Luk ([email protected] ) - Discussion section: Tu 2-3, 299 Cory Murali Rangan ([email protected] ) - Discussion section: F 10-11 299 Cory Artur Rivilis ([email protected] ) - Discussion section: W 1-2, 299 Cory Office hours: TBD 4 EE122, Fall ‘05 Overview Administrivia Overview and History of the Internet 5 EE122, Fall ‘05 Administrivia Course Web page: - http://inst.eecs.berkeley.edu/~ee122/ - Check often to get the latest information Deadlines - HWs: due 3:50 pm on the indicated date (10 minutes before lecture) Exams are closed-book, with open crib sheet Come to office hours, request an appointment, communicate by e-mail - We are here to help, including general advice! - TAs first line for help with programming problems Give us suggestions/complaints as early as possible 6 EE122, Fall ‘05 Course Goals Learn the main architectural concepts and technological components of communication networks, with the Internet as the overarching example - Understand how the Internet works - And why the Internet is the way it is Apply what you learned in three mini-class projects

inst.eecs.berkeley.eduee122/fa05/notes/01-overviewx6.pdf · Communication medium: electron, photon Network components: - Links – carry bits from one place to another (or maybe multiple

  • Upload
    others

  • View
    2

  • Download
    0

Embed Size (px)

Citation preview

Page 1: inst.eecs.berkeley.eduee122/fa05/notes/01-overviewx6.pdf · Communication medium: electron, photon Network components: - Links – carry bits from one place to another (or maybe multiple

Page 1

1EE122, Fall ‘05

EECS 122:Introduction to Computer Networks

Course Goals and Overview

Computer Science Division

Department of Electrical Engineering and Computer Sciences

University of California, Berkeley

Berkeley, CA 94720-1776

2EE122, Fall ‘05

Instructors

� Instructor: Ion Stoica ([email protected]) - Office Hours: W 2-3 PM, 645 Soda Hall

� Textbooks- L. L. Peterson and B. Davie, Computer Networks: A System

Approach, 3nd Edition, Morgan Kaufman, San Francisco, 2003.

- W. R. Stevens, B. Fenner, A. M. Rudoff, Unix Network Programming: The Sockets Networking API, Vol. 1, 3rd Ed., Addison-Wesley, Boston, 2004.

3EE122, Fall ‘05

TAs

� Jana Van Gruenen ([email protected])- Discussion section: Th 11-12 299 Cory

� Rowena Luk ([email protected])- Discussion section: Tu 2-3, 299 Cory

� Murali Rangan ([email protected])- Discussion section: F 10-11 299 Cory

� Artur Rivilis ([email protected])- Discussion section: W 1-2, 299 Cory

� Office hours: TBD

4EE122, Fall ‘05

Overview

� Administrivia� Overview and History of the Internet

5EE122, Fall ‘05

Administrivia

� Course Web page: - http://inst.eecs.berkeley.edu/~ee122/- Check often to get the latest information

� Deadlines- HWs: due 3:50 pm on the indicated date (10 minutes

before lecture)� Exams are closed-book, with open crib sheet� Come to office hours, request an appointment,

communicate by e-mail- We are here to help, including general advice!- TAs first line for help with programming problems

� Give us suggestions/complaints as early as possible

6EE122, Fall ‘05

Course Goals

� Learn the main architectural concepts and technological components of communication networks, with the Internet as the overarching example

- Understand how the Internet works

- And why the Internet is the way it is� Apply what you learned in three mini-class projects

Page 2: inst.eecs.berkeley.eduee122/fa05/notes/01-overviewx6.pdf · Communication medium: electron, photon Network components: - Links – carry bits from one place to another (or maybe multiple

Page 2

7EE122, Fall ‘05

Class Workload

� Four homeworks spread over the semester- Strict deadlines and due dates (no slip days!)

� Three (mini-)projects- 1st and 3rd are part of a larger project, which involves

implementing a comprehensive network application

• C (or C++) required

- 2nd is a simulation project � One midterm exams

- October 17� Final exam

- December 17

- Note dates and plan your travel accordingly!

8EE122, Fall ‘05

Grading

� Consultation on HWs is OK, but must hand in own work- Correlation between understanding HWs and doing well on exams

� Course graded to mean of B- Relatively easy to get a B, harder to get an A or a C- 10% A, 15% A-, 15% B+, 20% B, 15% B-, 15% C+, 10% C- A+ reserved for superstars (only 1 or 2 per class)- Mean can shift up for an especially great class

20%Final exam

20%Midterm exam

40%

(10% + 10% + 20%)

Projects

20%

(5% each)

Homeworks

9EE122, Fall ‘05

Overview

� Administrivia� Overview and History of the Internet

• See http://www.isoc.org/internet/history/ for more details

10EE122, Fall ‘05

What do this two have in Common?

� First printing press� Key idea: splitting up text in

individual components- E.g., lower, upper case letters

� Bible: first mass produced book

Johann Gutenberg(1398-1468)

The Internet

Both lower the cost of distributing information Both lower the cost of distributing information

11EE122, Fall ‘05

What is a Communication Network?(End-system Centric View)

� Network offers one basic service: move information- Bird, fire, messenger, truck, telegraph, telephone, Internet …- Another example, transportation service: move objects

• Horse, train, truck, airplane ...� What distinguish different types of networks?

- The services they provide� What distinguish the services?

- Latency- Bandwidth- Loss rate- Number of end systems- Service interface (how to invoke the service?)- Others

• Reliability, unicast vs. multicast, real-time...

12EE122, Fall ‘05

What is a Communication Network?(Infrastructure Centric View)

� Communication medium: electron, photon� Network components:

- Links – carry bits from one place to another (or maybe multiple places): fiber, copper, satellite, …

- Interfaces – attach devices to links

- Switches/routers – interconnect links: electronic/optic, crossbar/Banyan

- Hosts – communication endpoints: workstations, PDAs, cell phones, toasters

� Protocols – rules governing communication between nodes- TCP/IP, ATM, MPLS, SONET, Ethernet, X.25

� Applications: Web browser, X Windows, FTP, ...

Page 3: inst.eecs.berkeley.eduee122/fa05/notes/01-overviewx6.pdf · Communication medium: electron, photon Network components: - Links – carry bits from one place to another (or maybe multiple

Page 3

13EE122, Fall ‘05

Network Components (Examples)

��� ����� �

���� �� ���������� �

Links Interfaces Switches/routers��� ����� ����������� �

��� � ��� ����������� �

����� ����� � �� ���

!"��� ��#��������%$&� � �'�

14EE122, Fall ‘05

Types of Networks

� Geographical distance- Local Area Networks (LAN): Ethernet, Token ring, FDDI- Metropolitan Area Networks (MAN): DQDB, SMDS- Wide Area Networks (WAN): X.25, ATM, frame relay- Caveat: LAN, MAN, WAN may mean different things

• Service, network technology, networks� Information type

- Data networks vs. telecommunication networks� Application type

- Special purpose networks: airline reservation network, banking network, credit card network, telephony

- General purpose network: Internet

15EE122, Fall ‘05

Types of Networks

� Right to use- Private: enterprise networks- Public: telephony network, Internet

� Ownership of protocols- Proprietary: IBM System Network Architecture (SNA)- Open: Internet Protocol (IP)

� Technologies- Terrestrial vs. satellite- Wired vs. wireless

� Protocols- IP, AppleTalk, SNA

16EE122, Fall ‘05

The Internet (cont’d)

� Global scale, general purpose, heterogeneous-technologies, public, computer network

� Internet Protocol- Open standard: Internet Engineering Task Force (IETF) as

standard body ( http://www.ietf.org )

- Technical basis for other types of networks

• Intranet: enterprise IP network� Developed by the research community

17EE122, Fall ‘05

Services Provided by the Internet� Shared access to computing resources

- telnet (1970’s)� Shared access to data/files

- FTP, NFS, AFS (1980’s)� Communication medium over which people interact

- email (1980’s), on-line chat rooms, instant messaging (1990’s)- audio, video (1990’s, early 00’s)

• replacing telephone network?� Medium for information dissemination

- USENET (1980’s)- WWW (1990’s)

• replacing newspaper, magazine?- Audio, video (late 90’s, early 00’s)

• replacing radio, TV?- File sharing (late 90’s, early 00’s)

18EE122, Fall ‘05

Growth of the Internet

Number of Hosts on the Internet:Aug. 1981 213Oct. 1984 1,024Dec. 1987 28,174 Oct. 1990 313,000

Oct. 1993 2,056,000Apr. 1995 5,706,000Jan. 1997 16,146,000Jan. 1999 56,218,000Jan. 2001 109,374,000

Jan. 2003 171,638,297Jan. 2005 317,646,084

1

10

100

1000

10000

100000

1000000

10000000

100000000

1000000000

1981 1985 1989 1993 1997 2001

Data available at: http://www.isc.org/

Estimated number of users: http://www.internetworldstats.com/stats.htm

Page 4: inst.eecs.berkeley.eduee122/fa05/notes/01-overviewx6.pdf · Communication medium: electron, photon Network components: - Links – carry bits from one place to another (or maybe multiple

Page 4

19EE122, Fall ‘05

Internet vs. Telephone Net

� Strengths

- Intelligence at ends

- Decentralized control

- Operates over heterogeneous access technologies

� Weaknesses

- No differential service

- Variable performance delay - New functions difficult to add

since end nodes must be upgraded

- No trusted infrastructure

� Strengths

- No end-point intelligence

- Excellent voice performance� Weaknesses

- Achieves performance byoverprovisioning resources

- Difficult to add new services to “Intelligent Network” due to complex call model

- Expensive approach for reliability

Internet: “intelligent” edge, “dump” core

Internet: “intelligent” edge, “dump” core

Telephone Net: “dump” edge, “intelligent” core

Telephone Net: “dump” edge, “intelligent” core

20EE122, Fall ‘05

History of the Internet

� 68-70’s: started as a research project, 56 kbps, initially 4 nodes (UCLA, UCSB, SRI, Utah) then < 100 computers

- http://www.cnn.com/2004/TECH/internet/08/29/internet.birthday.ap/index.html

� 80-83: TCP/IP, DNS; ARPANET and MILNET split � 85-86: NSF builds NSFNET as backbone, links 6

Supercomputer centers, 1.5 Mbps, 10,000 computers� 87-90: link regional networks, NSI (NASA), ESNet (DOE),

DARTnet, TWBNet (DARPA), 100,000 computers� 90-92: NSFNET moves to 45 Mbps, 16 mid-level networks� 94: NSF backbone dismantled, multiple private backbones;

Introduction of Commercial Internet� Today: backbones run at 10 Gbps, close to 200 millions

computers in 150 countries

21EE122, Fall ‘05

The ARPANet

� Paul Baran- RAND Corp, early 1960s

- Communications networks that would survive a major enemy attack

� ARPANet: Research vehicle for “Resource Sharing Computer Networks”

- 2 September 1969: UCLA first node on the ARPANet

- December 1969: 4 nodes connected by phone lines

����������

� ������ �������

����������������

� !��"# $�#&% �� �'# (

)�)�*,+.-�/ 01+�2�/ +43 045�6 -�07-98�+�-�:+.2�-;3 8�+.-�<.= /�> -?0@-�A�A�/�B -C5�<.D�>�-�A�A�D�<

22EE122, Fall ‘05

ARPANet Evolves into Internet

EGF H4I�J�(K �� L���4M�N �� O9N F7����#�(�9LP !F�Q.L.F� SRT���.U�V H�J.L.F�9LP !F�Q.L.F� �W�X�U�"���L��.F�(

��O�O�N � U.�! �� J�L@I�JS(Y �� L������# Z���O�O9N � U.�! �� J�L@��F�QP[�� U.F@#�QSJ\[�� ] F�Q��� # Z���O�O�N � US�P �� J�L�� L.^.Q!��(Y !Q!M�U. !M�Q!F#�Q.J.[�� ]�F�Q�_ F�`KU�J�����F�QPU.F@ SJ�J�Va� Sb�F\ !U\c d

����#���e�F. ����fge�F. #���e�F\

f� #�h!��#ie���j�e�F. k$�F�Q!F��.M�N �P �� J�L7l�J�����F�Q!U�� ��N � m��P �� J�L

% ���9n % ���9n % ��o�n % ����n R�����nEGEGE

�9��#����#��� #

����fge�F. SZ����\ !F�N � !F4L.F. !p�J.Q.V#���e�F. SZ����.]�� J@e�F. !p�J.QSV

23EE122, Fall ‘05

24EE122, Fall ‘05

Page 5: inst.eecs.berkeley.eduee122/fa05/notes/01-overviewx6.pdf · Communication medium: electron, photon Network components: - Links – carry bits from one place to another (or maybe multiple

Page 5

25EE122, Fall ‘05

26EE122, Fall ‘05

Parallel Backbones

����������� ����������������������������� �!�#"$&%('���)*�+�����,�-�.���/10324������ 56�����7�3�-5���%8��'����������������

27EE122, Fall ‘05

Network “ Cloud”

28EE122, Fall ‘05

9;:=<;> ?A@8BDCE�:AF

Regional Nets + Backbone

9;:=<;> ?G@8BDCE�:AF 9;:=<;> ?G@8BDC

E�:AF

9;:=<;> ?A@8BDCE�:AF 9;:=<;> ?G@8BDC

E�:AF9;:=<;> ?G@8BDCE�:AF

H=BJIAKGLM?=@8:

����e ����e����e

����e7Z�� J.U.��NS��Q!F�� e�F� !p�J.Q.V

29EE122, Fall ‘05

N=OQP

Backbones + NAPs + ISPs

NROQP

N=OSPN=OQP

HDT8U=> @J:AUVUN=OSP W ?=@JUJTAXY:DZN=OQP

����e ����e����e

e���# e��g#H=B8IGKAL=?=@8:AU

$�� ��N `KM�O

�9��# Z\� LP !F�Q.L.F� ���F�QP[ � U.F@#�Q.J.[�� ]�Fe���# Z e�F. !p�J.Q.V@��U.USF�(S(�#�J�� LS

30EE122, Fall ‘05

W ?=Z[:E�:AFV\]?=ZVKVU

W ?A^JBA_

Core Networks + Access Networks

`�a ?=Xb:

NROQPW > @8<=T;C BAZ

ObcJZ8> @8F dQe�f

����e ����e����e

e���#

$�� ��N `KM\O

$�����7N p��hg (�J.L

e���#

���H�N FI�F��.]&W�L.]9(

�F�N N�F�N N

FaN N

���P !F�N N � !Fj�� X�F�]4E � Q!F�N F (P(

Page 6: inst.eecs.berkeley.eduee122/fa05/notes/01-overviewx6.pdf · Communication medium: electron, photon Network components: - Links – carry bits from one place to another (or maybe multiple

Page 6

31EE122, Fall ‘05

W ?A^JBA_

Computers Inside the Core

`�a ?=Xb:

N=OQPW > @8<=T;C BAZ

ObcJZ8> @8F dQe�f

����e ����e����e

e���#

$�� ��N `KM�O

$g�����N p��hg (�J.L

e���#

��\HaN FI�F��.] W�L\]9(

�F�N N�F�N N

F�N N

���P !F�N N � !Fj�� X F�]4E � QPF�N F (!(

32EE122, Fall ‘05

The Evolution of the Enterprise

#�Q�� [.�P !F@�J.QSO�J\Q!�. !Fe�F. !p�J.Q.V

$�F�]�� U.�P !F�]&^S�.U�� N � �� F (PhU�J���O.MP SF�Q�U.F L. !F�QS(

$�F�]�� U.�P !F�]&�\O�O�N � U.�P �� J�L�(Ph��QP] O.�.QP g $���� �W�c ��c b��7Q!�.U�N F

f BJFV:��������=U�9LS !F�QSL.��N.M�(!F�QS(

��� �7� !F�]4U�M\(Y SJ���F QPhF�X� !F�QSL.��N.�SU.U.F (.(

33EE122, Fall ‘05

The Evolution of the Enterprise

#�Q�� [.�P !F@�J.QSO�J\Q!�. !Fe�F. !p�J.Q.V

$�F�]�� U.�P !F�]&^S�.U�� N � �� F (PhU�J���O.MP SF�Q�U.F L. !F�QS(

�7M. S(.J.M.Q!U.F�] KW�LP !F�Q.O.Q�� (PF@��F (.J.M.Q!U.F

#�N �SL�L�� L.������O�O�(F c ��c b.#�F J�O�N F ��J.^P

��������9LS !F�QSL.��N.M�(!F�QS(

��� �7� !F�]4U�M\(Y SJ���F QPhF�X� !F�QSL.��N.�SU.U.F (.(

34EE122, Fall ‘05

The Evolution of the Enterprise

�7M. S(.J.M.Q!U.F�]EGF�H4I�J�(Y �� L��

$�F�]�� US�P !F�]?j��.U�� N � g��M. S(.J.M.QPUSF�]W���#@��O�O.(

���������LP !F�QSL\� N.M�(PF�QS(

�9LP !F�Q.L.F�

W�X� !F�QSL.��N. M�(P SJ���F�QS(

��� QK !M.��NS#�Q�� [.�! !F4e�F� !p�J\QSV����#@�'F (!"

35EE122, Fall ‘05

The Evolution of the Enterprise

��M. S(.J.M.QPUSF�]EGF H4I�J�(Y �� L�� $�F�]�� US�P !F�]?j��.U�� N � g

��M. S(.J.M.QPUSF�]W���#@��O�O.(

���������LP !F�QSL\� N.M�(PF�QS(

�9LP !F�Q.L.F�

W�X� !F�QSL.��N. M�(P SJ���F�QS(

��� QK !M.��NS#�Q�� [.�! !F4e�F� !p�J\QSV�9��#�'F (."

�9LP !F�QSL.F� ��F�QP[�� U.F (

��F��.QPU\"��.U�"�� L����]�(W��J����

����� �

36EE122, Fall ‘05

The Evolution of the Enterprise

������� � �!#"�� $&%�'(*)&+-,�� �)�.&+�$#,�� /�)�+

0�1�1�1

2�3�'4"�$�5�)�+�'

26$�%#"-)�%#"�7*)8� � ,�)�+49;: <�)�"�=

>�+#/;.�!�+?"?9@�!� �� � � "�� )�'�ACB�5D"

2�!� �E6� %�BGFAH)�/D� !�(D)�+-,�)�+�'

IJ%#"-)&+�%�)&"(D)�+#,�� �)�'

(D)�!�+# KE2�!� �E�)�L/6'M�26$�5�5

N�3�"�'�$�3�+# �)&/OP)�Q;R�$�'4"�� %&B

����� �

IJ(D.�A;)�'#E

S8.�<�'

Page 7: inst.eecs.berkeley.eduee122/fa05/notes/01-overviewx6.pdf · Communication medium: electron, photon Network components: - Links – carry bits from one place to another (or maybe multiple

Page 7

37EE122, Fall ‘05

Services Within the Network: Content Distribution

������������ ��.�!�+-!�� � )��K<�)�"���$�+�����!� ���Q�$�%�)�'IJ%#"-)&+�%�)&"�M��� �E&!K%&B�)�.�$&� %#"�'

����������� �"!�# ��$

(* �!�� !�Q6� );(D)�+-,�)�+�'

%&('���"� ���

38EE122, Fall ‘05

P2P Services in the Internet:Napster, Gnutella, BitTorent, …

)*)+)26$�� /J�&� !#9 (L��)�)�/$�, (D$�3�%�/��+&� "�%K)�9C(L��)�!�+�' 2*� %�/�)�+#)6� � !

)*)+)

- # . �"!/��.+0 �1 .�2�# �

3��4 # � ! .65708�"��9+0: # $�;85 ���"��9*0

������< � .

= . # ;8� ��5�9"> !�# $ 4�?��� ��. # $ 4 . �� ��>�.�� @�"A/ $ � '1B # $ 4 �"� B B � ' ��.��"!�# ��$

C �!K%�Q&)�/D� '4"-+&� Q&3�"-)�/!� �+�$�'�' ��)�)�+�'�D

39EE122, Fall ‘05

Summary

E Course administrative triviaE Internet history and background