sdy50_b

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opusMAGNUM

ISBN: 978-960-538-919-2 : 50/

Copyright 2013

18, 26335 .: 2610 367300, : 2610 367650

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2013

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1

.

,,-,

................................................................................131.1 ........................................................................................................161.2 ; ..............................191.3 ...........................................22

1.4 .......................23

1.5 ...............25

1.5.1 ..................................................26

1.5.2 ......................................28

1.5.3 ......................................................................301.6 .................................33 ...................................................................................................................35

.....................................................................................36 .........................................................................................................37 ..........................................................................38

.....................................................39 ..............................................................................42

8 :

2

.

,,-,

................................................................................47

2.1 ...........................................................................50

2.1.1 ..........................................................................................50

2.1.2 .........................................................................................53

2.1.3 ............................................................................................57

2.1.4 .........................................................58

2.1.5 ...........................................................................................602.2 ..................................................62

2.2.1 - ........................................................62

2.2.2 - ................................64

2.2.3 ...............................................................................68

...................................................................................................................70 .....................................................................................71 .........................................................................................................72

..........................................................................73 .....................................................74

..............................................................................77

3

.

,,-,

................................................................................83

3.1 ...........................................................................................86

3.2 .................................88

3.3 ..........................................................................................93

9

...................................................................................................................98

.....................................................................................99 .......................................................................................................100 ........................................................................101 ...................................................102

............................................................................104

4

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..............................................................................1074.1 .....................................1104.2 .................................................1134.3 ...............................115

4.3.1

SOAP ...................................................................115

4.3.2

REST .............................................120

4.4 WSDL .......................................125

4.5 .................................................................134

4.6 ............135

4.7 ......................................................................................138

.................................................................................................................142

...................................................................................143

.......................................................................................................144

........................................................................146

...................................................147

............................................................................149

1 0 :

5

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,,-,

..............................................................................155

5.1 .................................................................................................159

5.2

P2P .............................................................1615.3 P2P .................................................................166 .................................................................................................................171 ...................................................................................172

.......................................................................................................173 ........................................................................175

...................................................176 ............................................................................178

..............................................................................................................181

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Accetta, M., Baron, R., Golub, D., Rashid, R., Tevanian, A. & Young, M. (1986).

Mach: A New Kernel Foundation for UNIX Development. In Proceedings of the

Summer 1986 USENIX Conference, pp. 93-112. 2012,

http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.91.3964

Coulouris, G., Dollimore, J., Kindberg, T. & Blair, G. (2011). Distributed Systems:

Concepts and Design. 5th edition. Pearson Education, NJ: Addison-Wesley

Emmerich, W. (1997). Distributed System Principles. 2012,

http://www.cs.ucl.ac.uk/staff/ucacwxe/lectures/ds98-99/dsee3.pdf

Flynn, M. (1972). Some Computer Organizations and their Effectiveness. IEEE

Transactions on Computers, 21(9), pp. 948-960. Doi: 10.1109/TC.1972.5009071

Lamport, L. (1987). Distribution email, Msg-Id:. - 2012, http://research.microsoft.com/en-us/um/people/lamport/pubs/distrib-uted-system.txt

Rozier, M., Abrossimov, V., Armand, F., Boule, I., Gien, M., Guillemont, M.,

Herrman, F., Kaiser, C., Langlois, S., Leonard, P. & Neuhauser, W. (1991). Overview

of the Chorus Distributed Operating System. Computing Systems Journal, 1, pp.

39-69. 2012, http://citeseerx.ist.psu.edu/viewdoc/

summary?doi=10.1.1.38.6843

Tanenbaum, A. (2007). Modern Operating Systems. 3rd edition. Upper Saddle River,

NJ: Prentice Hall

Tanenbaum, A., van Renesse, R., van Staveren, H., Sharp, G., Mullender, S., Jansen,

J. & van Rossum, G. (1990). Experiences with the Amoeba Distributed Operating

System. Communications of the ACM, 33(12), pp. 46-63. Doi: 10.1145/96267.96281

Tanenbaum, A. & Van Steen, M. (2006). Distributed Systems: Principles and Para-digms. 2nd edition. Upper Saddle River, NJ: Prentice Hall

3 8 1 :

Coulouris, G., Dollimore, J., Kindberg, T. & Blair, G. (2011). Distributed Systems: Concepts and Design. 5th edition. Pearson Education, NJ: Addi-son-Wesley.

.

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Tanenbaum, A. & Van Steen, M. (2006). Distributed Systems: Principles and Paradigms. 2nd edition. Upper Saddle River, NJ: Prentice Hall. . - , , ,

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Farooqui, K., Logrippo, L. & de Meer, J. (1995). The ISO Reference Model for Open

Distributed Processing: An Introduction. Computer Networks and ISDN Systems,

27(8), pp. 1215-1229. Doi: 10.1016/0169-7552(95)00087-N

Kshemkalyani, A.D. & Singhal, M. (2008). Distributed Computing Principles, Algo-rithms, and Systems. New York: Cambridge University Press

Lamport, L., Shostak, R. & Pease, M. (1982). Byzantine Generals Problem. ACM

TOPLAS, 4(3), pp. 382-401. Doi: 10.1145/357172.357176

7 3

Kshemkalyani, A.D. & Singhal, M. (2008). Distributed Computing Prin-ciples, Algorithms, and Systems. New York: Cambridge University Press. ,

, - .

Coulouris, G., Dollimore, J., Kindberg, T. & Blair, G. (2011). Distributed Systems: Concepts and Design. 5th edition. Pearson Education, NJ: Addi-son-Wesley. 2

- .

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, .

(system call). , ,

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. , - ,

. ,

, ,

.

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.

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M (Liskov, 1991).

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);

( : 15)

3 . 1 8 7

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. ( 200 ) ,

.

.

( : 30)

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, (total

ordering):

(), , a

b, a -

b (Krzyzanowski, 2002).

, . -

,

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: ab a

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b -

, ab (

). :

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a b ,

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(

), ab . -

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Lamport

,

. :

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.

-

( -

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, , ,

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, ab, L(a) < L(b), L(x) - Lamport x.

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e

e, L(e) < L(e). , . Lamport, L(e) < L(e), ee. , Lamport

.

-

(Mattern, 1989).

. (Vi

pi) .

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3 . 2 9 1

( ) .

:

1. 0 :

Vi[j] = 0 i, j = 1, , N

2. pi , -

:

Vi[i] = V

i[i]+1

3. pi V

i.

3.3

4. pj t, -

--,

:

Vj[i] = max(Vj[i], t[i]) i = 1, , N

:

V = V, V[j] = V[j] j = 1, , N

V V, V[j] V[j] j = 1, , N

9 2 3 :

e e, ee, V(e) < V(e).

Lamport. , ,

, V(e) < V(e), ee. e e , V(e) V(e), V(e) V(e). , b f 3.3, , - .

, -

(Krzyzanowski,

2002).

3.1

-

p1, p

2 p

3:

-

:

) (Lamport)

) .

3 . 3 9 3

3.3

H/Y CMOS

. -

/ .

sec 10 ,

, -

. ,

31C sec (Krzyzanowski, 2002).

, / ,

, (clock drift).

- (clock skew)

-

.

(UTC) x- / y-. -

.

, -

.

.

, ,

. , , -

,

-

.

-. ,

.

-

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9 4 3 :

function) (. 3.4). , -

/

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(Krzyzanowski, 2002)

, , -

. GPS (Global Positioning

System) / ( GPS 1msec

UTC). ,

.

/, -

(time servers).

.

Cristian

Cristian (Cristian, 1989)

, (intranets) .

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3 . 3 9 5

(Round-Trip Time RTT) -

.

Cristian P - S, UTC. :

1. P S.

2. S P, .

3. P T + RTT/2.

P , , RTT S . RTT ,

,

LAN. -

S RTT.

Berkeley

Berkeley (Gusella & Zatti, 1989) -

, / -

. Cristian, -

.

Berkeley, -, -

(master), , , - (slave

processes). :

1. .

2. -, -

,

Cristian.

3. RTT

, .

9 6 3 :

4. ,

( ).

5. ,

( )

.

( RTT) .

,

. Gusella Zatti -

15 /

20-25msec,

Berkeley.

3.2

( -

), -

:

1. / Lamport

:

) .

)

.

) .

) .

2. / - Lamport :

) .

) -

.

) .

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) .

4. Cristian Berkeley

:

) .

) .

) .

5. /

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.

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.

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.

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/.

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) .

9 8 3 :

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- .

. ,

Lamport ( - /)

Cristian Berkeley - .

9 9

,

:

, -

-

-

,

Lamport -

Lamport

Cristian Berkeley -

.

1 0 0 3 :



Cristian, F. (1989). Probabilistic Clock Synchronization. Distributed Computing,

3(3), pp. 146-158. Doi: 10.1007/BF01784024

Giridhar, A. & Kumar, P.R. (2006). Distributed Clock Synchronization over Wireless

Networks: Algorithms and Analysis. Proceedings of the 45th IEEE Conference on

Decision and Control (CDC2006), pp. 4915-4920. Doi: 10.1109/CDC.2006.377325

Gusella, R. & Zatti, S. (1989). The Accuracy of the Clock Synchronization Achieved

by TEMPO in Berkeley UNIX 4.3BSD. IEEE Transactions on Software Engineering,

15(7), pp. 847-853. Doi:10.1109/32.29484

Krzyzanowski, P. (2002). Clock Synchronization. Lectures on Distributed Systems.

Lamport, L. (1978). Time, Clocks, and the Ordering of Events in a Distributed System.

Communications of the ACM, 21(7), pp. 558-565. Doi: 10.1145/359545.359563

Liskov, B. (1991). Practical Uses of Synchronized Clocks in Distributed Systems.

Distributed Computing, 6(4), pp. 211-219. Doi: 10.1007/BF02242709

Mattern, F. (1989). Virtual Time and Global States of Distributed Systems. In

Cosnard, M., Yves, R., Patrice, Q. & Michel, R. (eds). Parallel and Distributed

Algorithms, pp. 215-226. Elsevier Science Publishers

Sundararaman, B., Buy, U. & Kshemkalyani, A.D. (2005). Clock Synchronization

for Wireless Sensor Networks: A Survey. Ad Hoc Networks, 3(3), pp. 281-323. Doi:

10.1016/j.adhoc.2005.01.002

1 0 1

Sundararaman, B., Buy, U. & Kshemkalyani, A.D. (2005). Clock Synchro-nization for Wireless Sensor Networks: A Survey. Ad Hoc Networks, 3(3),

pp. 281-323. Doi: 10.1016/j.adhoc.2005.01.002.

-

, -

, , ,

.

-

-

. ,

.

1 0 2 3 :

3.1

) (Lamport):

)

( mi, i = 1, ..., 6, -

):

, - 3.2. , !

, 3.2.

1 0 3

3.2

A/A

/

1 )

,

( )

( -

), (

Lamport).

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-

(.. a e

3.3),

Lamport.

3 )

(..

b f 3.3).

4 ) Cristian Berkeley RTT,

-

.

5 ), )

Cristian

. , -

/,

(

RTT Berkeley).

6 )

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(

),

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, ! -, 3.2 ( 1, 2 3) 3.3 (- 4, 5 6).

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)

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.

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).

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.

.

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REST), , - . , - .

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UDDI

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2007).

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)

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registry), .

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/ ( 4-7):

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. , - (

).

-, ,

(Web Services Description

Language WSDL).

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(Simple Object Access Protocol SOAP), , ..,

.

- ( SOAP)

SOAP .

4.1

:

(service provider):

.

.

(service registry): - . - -.

(service consumer/requestor): - -

XML.

11 2 4 :

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,

, W3C

(Booth, Haas, McCabe, Newcomer, Champion, Ferris & Orchard, 2004):

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. ,

, (WSDL). - , - SOAP,

HTTP XML (serialization),

.

4 . 2 11 3

4.2

- . - , ,

.

(. 4.2):

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(transport layer):

HTTP, SMTP FTP.

XML : - XML,

.

XML-RPC, WS-Addressing SOAP.

:

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:

, -

11 4 4 :

. - , (Universal Description

Discovery and Integration UDDI) , .

4 . 3 11 5

4.3

:

, (SOAP) , - , REST. - .

4.3.1 SOAP

SOAP

(Coulouris, Dollimore, Kindberg & Blair,

2011). SOAP XML , , - HTTP (, ,

, SMTP, FTP ..).

SOAP W3C 1999,

1.2, 2007. , SOAP

, - WSDL UDDI.

SOAP - . SOAP : )

(envelope), - , ) (header),

) (body), - .

SOAP ( , ,

) 4.3.

. ,

SOAP

(pay-per-use).

SOAP

XML . -

11 6 4 :

. (child element)

SOAP.

SOAP XML-RPC, (Remote Procedure Call

RPC), XML HTTP

. XML-RPC, SOAP

( ), - , ( - ),

(.. HTTP, SMTP, FTP).

4.3

SOAP

- SOAP ( - HTTP).

:

GET /StockPrice HTTP/1.1

Host: example.org

ContentType: application/soap+xml; charset=utf8

ContentLength: nnn

4 . 3 11 7

81100

Monday

:

HTTP/1.1 200 OK

ContentType: application/soap+xml; charset=utf8

ContentLength: nnn

11 8 4 :

XML SOAP - . ,

, - , - -. , CORBA

./DCOM , .

-, , ,

,

, WSDL.

( )

, - (stub). , - , WSDL - .

, SOAP - SOAP ( -). , - / ,

( WSDL

).

, ,

( WSDL

) , ,

(

, , WSDL

).

4 . 3 11 9

4.4

SOAP

- (

URI )

WSDL.

- (. 4.4):

1. ,

. - SOAP.

(marshalling serialization). ,

- bytes.

2. SOAP - HTTP. SOAP

.

SOAP -, , , - (unmarshalling deserialization).

3. SOAP ,

,

.

4.

, SOAP.

1 2 0 4 :

5. SOAP - HTTP. - SOAP

.

6. , - .

4.3.2 REST

(Representational

State Transfer REST) - (Fielding, 2000). REST -, (RESTful) - . RESTful

URI. ,

,

.

. ,

(cached) . - ,

.

, , RESTful

Twitter, - (tweets) . ,

tweets

(. 4.5).

HTTP GET - (URI) :

http://twitter.com/statuses/user_timeline.xml?id=BarackObama &count=2

4 . 3 1 2 1

4.5

tweets

GET (.. Javascript,

PHP JSP )

.

, GET SQL SELECT - . (

HTTP) XML,

(

XML):

Wed May 09 00:21:03 +0000 2012

1 2 2 4 :

200017502510657536

Mitt Romney would "take a lot of credit" for the comeback of the auto industry. Another case of Romney vs. Reality: http://t.co/2mMQNRTA

web

false

751

813286

Barack Obama

BarackObama

Washington, DC

This account is run by #Obama2012 campaign staff.

https://si0.twimg.com/profile_images/

1735360254/icon_normal.jpg

http://www.barackobama.com

15126436

4 . 3 1 2 3

, - URI: , http://twitter.com -,

. /statuses

REST (

). Twitter, - (status) , /

. user_timeline.

.

() tweets

. .xml

. GET -,

(?). , (id

count) Twitter, - (BarackObama), - tweets (2).

, RESTful

SOAP1, -, :

1 (2012)

REST: Twitter, Yahoo, Flickr, del.icio.us .. eBay Amazon

REST SOAP.

1 2 4 4 :

XML (.

2 4.2)

- .

, REST ,

.., - .

4.1

SOAP REST;

( 300 )

, 2

3 Pautasso, Zimmermann & Leymann (2008).

( : 60)

4 . 4 WSDL 1 2 5

4.4 WSDL

WSDL XML

.

WSDL ( WSDL)

,

. WSDL

WSDL 2.0 ( W3C 2007).

H WSDL - (Application Programming Interface API), - , ,

,

. ,

, -

WSDL - .

WSDL

, , - , :

.

WSDL 2.0 (binding)

HTTP ( GET, POST, PUT

DELETE GET POST,

1.1). , RESTful

, . ,

WSDL 1.1

SOAP.

1 2 6 4 :

WSDL 2.0 XML (namespace)

http://www.w3.org/ns/wsdl. (root element)

(description), - -

:

(types)

(interface)

(binding)

(service).

WSDL 2.0 :

(Hotel Zeus)

WSDL,

- .

, - (Check_Availability). ,

/

,

.

,

(Booth & Liu, 2004).

4 . 4 WSDL 1 2 7

Hotel Zeus -. ,

(message types) - .

checkAvailability, checkAvailabilityResponse invalidDataError, - XML (elements).

1 2 8 4 :

H WSDL 2.0 - - .

(interface) WSDL 2.0

,

. - ,

, . -, in-out ,

,

( )

( ):

4 . 4 WSDL 1 2 9

(binding element)

(

). -,

. Hotel Zeus,

SOAP 1.2 HTTP - , .

REST,

HTTP.

(service element) - :

1 3 0 4 :

4.2

(web service client)

. (- WSDL) ( - ) URL: http://wsf.cdyne.com/WeatherWS/Weather.

asmx?WSDL

O ( HTML) - (Zip code) (. )

( Fahrenheit Celsius),

/ 6

(. ).

,

.

URL: http://zip4.usps.com/zip4/citytown.jsp.

Java Servlet (WeatherServlet.java)

HTML JSP (DynamicWeather.jsp).

, NetBeans.

tutorial

4 . 4 WSDL 1 3 1

NetBeans URL: http://netbeans.org/kb/docs/websvc/client.html

tutorials youtube.

( : 90)

1 3 2 4 :

4.1

, - .

:

1. ;

)

.

) .

) XML.

) .

2. :

) .

) .

)

.

) .

3. SOAP - ;

) SOAP

- (firewalls).

) SOAP HTML.

) SOAP LANs.

) .

4 . 4 WSDL 1 3 3

4. ( - ) .

) .

) .

5. SOAP REST :

) .

) SOAP - .

) SOAP

.

)

.

1 3 4 4 :

4.5

(discovery)

(

) . - (registry)

. - UDDI, - . UDDI

SOAP WSDL. , UDDI

, ( 2006

IBM, Microsoft SAP

UDDI ).

- (WS-Inspection),

Microsoft

IBM. H WS-Inspection - .

XML (, WS-Inspection

). -

. UDDI

WS-Inspection

.

(Web Services

Dynamic Discovery WS-Discovery), - . WS-Discovery

(multicast)

. - SOAP- -UDP. 2009

OASIS.

4 . 6 1 3 5

4.6

.

, - RMI, ./DCOM, CORBA, EDI ebXML (. 50/)

, , . , ,

;

, , HTTP, - XML .

( )

. , - (RMI, .NET/DCOM, CORBA) - ,

. -

(Cook & Barfield, 2006):

- , - XML. ,

C++ - Windows, - Java Linux.

HTTP

(

). - ,

(proxies) (firewalls)

HTTP (

CORBA, , , ).

CORBA, ./DCOM EJB - (tightly-coupled), - ,

-

1 3 6 4 :

(loosely-coupled),

, .

(intranet)

, . -, - ,

.

, :

: XML

, : , -, . , ,

, ,

.

: ,

,

( ) . CORBA, -,

, (persistency), (notifications),

, .. , - ( WS-Resource

WS-ResourceLifetime) .

4.3

SOAP - , . - SOAP - ,

WSDL, W3C - .

,

, ,

, .

4 . 6 1 3 7

- , ,

CORBA, ./DCOM J2EE. , , ,

, ,

- . ;

200 .

,

Vinoski (2003).

( : 60)

1 3 8 4 :

4.7

widgets2: , - , widget, - , - . widgets

, - , ,

, ..

, s - widgets.

, - ,

.

Amazon3, Facebook4, Tweeter

online .

:

,

,

.

- ,

Ajax (. 4.6).

.

.

2 widget

. widget

( ) - ,

.

3 , Product Advertising API Amazon - Amazon,

Amazon .

4 , Profile Badge Photo Badge widgets Facebook

, , - .

4 . 7 1 3 9

4.6

: (web services

composition) - ()

. , , - ,

(Dustdar &

Schreiner, 2005). , ,

online -

- -. , ,

.

(coordinator web service), -

1 4 0 4 :

.

.

, - (Business Process Execution Language BPEL)

. ,

(.. NetBeans, Eclipse) BPEL.

4.2

, - .

:

1. ()

:

) XML UDDI, .

) XML SOAP, .

) HTML HTTP, .

) HTML SOAP, .

2.

:

)

.

) - .

) -.

) ()

.

) .

4 . 7 1 4 1

3. (

) ,

) -/ .

) - .

) () - .

) .

4. ,

;

) - .

) .

) - SOAP REST.

5. , -, , - :

) WSDL.

) REST.

) UDDI.

) BPEL.

1 4 2 4 :

( ) - .

/ ( SOAP

REST), XML (WSDL)

(.. UDDI, WS-

Discovery). - , - . , ,

.

1 4 3

,

:

-

- SOAP REST

WSDL

UDDI, WS-Inspection WS-Discovery

( -, ) -

widgets, - ,

.

1 4 4 4 :



Booth, D., Haas, H., McCabe, F., Newcomer, E., Champion, M., Ferris, C. & Orchard,

D. (2004). Web Services Architecture. W3C Working Group Note. 5

2012, http://www.w3.org/TR/ws-arch/

Booth, D. & Liu, C.K. (2004). Web Services Description Language (WSDL) Version

2.0. W3C Working Draft. 5 2012, http://www.w3.org/

TR/2004/WD-wsdl20-primer-20041221/

Cook, W.R. & Barfield, J. (2006). Web Services versus Distributed Objects: A

Case Study of Performance and Interface Design. Proceedings of the International

Conference on Web Services (ICWS06), pp. 419-426. Doi: 10.1109/ICWS.2006.145

Daigneau, . (2011). Service Design Patterns: Fundamental Design Solutions for

SOAP/WSDL and RESTful Web Services. Addison-Wesley Professional

Dustdar, S. & Schreiner, W. (2005). A Survey on Web Services Composition.

International Journal of Web and Grid Services, 1(1), pp. 1-30. Doi: 10.1504/

IJWGS.2005.007545

Fielding, R.T. (2000). Architectural Styles and the Design of Network-based Software

Architectures, PhD Thesis, University of California, Irvine, 5

2012, http://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm

Mizouni, R., Serhani, M.A., Dssouli, R., Benharref, A. & Taleb, I. (2011).

Performance Evaluation of Mobile Web Services. Proceedings of the 9th IEEE

European Conference on Web Services (ECOWS2011), pp. 184-191. Doi: 10.1109/

ECOWS.2011.12

Papazoglou, M.P. (2007). Web Services: Principles and Technology. Pearson-

Prentice Hall

Pautasso, C., Zimmermann, O. & Leymann, F. (2008). Restful Web Services vs.

Big Web Services: Making the Right Architectural Decision. Proceedings of the

17th International Conference on World Wide Web (WWW08), pp. 805-814. Doi:

10.1145/1367497.1367606

1 4 5

Vinoski, S. (2003). Putting the Web into Web Services: Web Services Interaction

Models, Part 2. IEEE Internet Computing, 6(4), pp. 90-92. Doi: 10.1109/

MIC.2002.1020331

1 4 6 4 :

Daigneau, . (2011). Service Design Patterns: Fundamental Design Solutions for SOAP/WSDL and RESTful Web Services. Addison-Wesley Professional. - REST - SOAP/WSDL. -

.

, -

.

Mizouni, R., Serhani, M.A., Dssouli, R., Benharref, A. & Taleb, I. (2011).

Performance Evaluation of Mobile Web Services. Proceedings of the 9th IEEE European Conference on Web Services (ECOWS2011), pp. 184-191. Doi: 10.1109/ECOWS.2011.12.

- . -, - . ,

(Quality of Service QoS)

, .. , ,

.

1 4 7

4.1

A/A

/

1 )

- - --

( -).

2 )

,

,

-.

3 )

SOAP - ,

HTTP -

.

4 )

M RESTful , , - URI

, - .

5 ), )

SOAP

-

SOAP. , SOAP

XML

SOAP.

, . -, 4.1 ( 1, 2), 4.3.1 ( 3),

4.3.2 ( 4) 4.3 ( 5).

1 4 8 4 :

4.2

A/A

/

1 )

- -

SOAP. H - XML.

2 ), )

- ,

, , - (HTTP, XML). , - ,

-.

3 )

-,

- .

4 )

, , - - ,

.

5 )

H WSDL

, REST - BPEL

.

, . -, 4.3.1 ( 1), 4.6 ( 2), 4.7

( 3 4) 4.3.2, 4.4, 4.5, 4.7 ( 5).

1 4 9

4.1

REST SOAP - . -, . ,

REST --, SOAP

.

SOAP REST:

,

SOAP HTTP,

.

WSDL - - ,

(

). , SOAP

WSDL - .

REST SOAP:

REST , -

, . - -

RESTful , - - . RESTful

.

REST URIs

. , URIs -, REST

1 5 0 4 :

, - ( UDDI).

. -, , - SOAP

REST. , - 2 3 Pautasso et al. (2008)

4.3.1 4.3.2 ,

- SOAP REST.

4.2

Java processRequest Servlet

WeatherServlet:

protected void processRequest(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

response.setContentType("text/html;charset=UTF-8");

PrintWriter out = response.getWriter();

String zipCode = request.getParameter("zip");

WeatherReturn today = null;

try {

today = getCityWeatherByZIP(zipCode);

double celsius = Math.round(((new Double(today.getTemperature())) - 32) / 1.8);

ForecastReturn forecast = getCityForecastByZIP(zipCode);

Object[] fc = forecast.getForecastResult().getForecast().toArray();

1 5 1

int num_of_days = fc.length;

out.println("-

");

out.println("H

" + today.getCity() + " (zip code: " + zipCode + "):"+today.getTemperature()+"(Fahrenheit):"+celsius+"(Celsius)");

for (int i = 1; i < num_of_days; i++) {

Forecast f = (Forecast) fc[i];

String theDate = f.getDate().getDay() + "-" + f.getDate().getMonth() + "-" + f.getDate().getYear();

out.println("O"+theDate

+ " : " +

f.getTemperatures().getMorningLow()+"

"+f.getTemperatures().getDaytimeHigh()+"(

Fahrenheit)");

}

out.println("");

} catch (Exception ex) {

out.println("zip

code...");

out.println("zipcode\""+zipCode+"\"

!...");

out.println("");

}finally{

1 5 2 4 :

out.close();

}

}

,

NetBeans

getCityWeatherByZIP getCityForecastByZIP.

, - . ,

tutorial (http://

netbeans.org/kb/docs/websvc/client.html).

4.3

-,

. - - . - ,

(SOAP, WSDL, UDDI, Web Services

Choreography Definition Language ..) - - .

, ,

. - WSDL

(bindings)

. ,

- ,

1 5 3

-, - , , ,

.

.

, , - -. , Vinoski

(2003), 4.3.1 4.6 - SOAP

( CORBA), .

.

(Peer-to-Peer P2P) . -

-, P2P -

. -

, P2P

, , -

P2P -

.

,

:

P2P

P2P

P2P

-

P2P

P2P

.

-

5

1 5 6 5 :

P2P

P2P

Napster

BitTorrent

Gnutella

Pastry

P2P -

( )

. , /

. / / .

P2P ( -

) (.. , -

, , ..), -

/ (hosts).

,

, -

- (client-server),

() () (Kwok, 2011).

P2P -

, , -

,

/ , /, -

.

, , ,

,

. , , -

, P2P , -

, ,

(Androutsellis-Theotokis & Spinellis, 2004).

, P2P

1 5 7

-

.

P2P -

, ,

, -

. P2P -

, . P2P

(Coulouris, Dollimore,

Kindberg & Blair, 2011):

P2P ,

,

, ,

-

-

-

/ ,

,

, -

/, .

, P2P ,

P2P -

, (Androutsellis-Theotokis & Spinellis,

2004):

1 5 8 5 :

P2P -

( , CPU, -

). P2P -

, -

, -

.

P2P . -

P2P .

P2P .

, -

P2P ,

.

5 . 1 1 5 9

5.1

P2P - , :

(.. -, ..) .

. , ,

, -. , , (,

) P2P .

. -, -, ,

(persistent) .

.

(accountability),

(anonymity) (censorship),

(, , ).

, , - . - / (chat/Instant Messaging IM),

IRC, ICQ, Yahoo IM, MSN IM Jabber.

1 6 0 5 :

IP

P2P IP

(Voice over IP VoIP),

,

. Skype - P2P VoIP. Skype

P2P Kazaa,

( ) - . - ,

Skype .

( CPU) P2P -. -

, , ,

. ,

,

. - Seti@home ..

5 . 2 P 2P 1 6 1

5.2 P2P

(lifecycle) P2P

: (join), (query), (download)

(depart). ,

P2P .

(

) , ,

. , - . (, - IP ), - ( ). ,

P2P .

P2P ,

IP

. , P2P

( DNS)

.

, , P2P

(application layer)

,

.

, P2P - (overlay network), ,

. - (indexing)

(peer discovery) P2P

. , , ,

IP (Lua, Crowcroft, Pias, Sharma & Lim, 2005).

P2P , - . (links)

. ,

P2P ,

1 6 2 5 :

,

. P2P (unstructured)

(structured),

(Androutsellis-Theotokis & Spinellis, 2004).

- ( ),

( ).

P2P

P2P - ( ). , - ()

. ,

- ,

, .

P2P ,

, - (flooding),

.

.

,

. -, , , ,

, , . ,

P2P , , ,

-. , P2P - , , ,

.

P2P :

(centralized) P2P ,

-

5 . 2 P 2P 1 6 3

(bootstrapping) , - (directory)

( -), (.

5.1). Napster, eDonkey

BitTorrent.

(pure) P2P ,

, - ( servents: SERVers + clieENTS) (.

5.1). , - . , -

(infrastructure nodes). P2P - Gnutella ( v0.4)

Freenet.

(hybrid) P2P , - (supernodes super peers) (. - 5.1). ,

,

.

P2P .

Kazaa,

Gnutella ( v0.4) Gnutella2.

P2P

P2P , (, , )

, , - . - ( ) - . , ,

(.. )

(.. ),

,

1 6 4 5 :

,

(. 5.1).

5.1

P2P : ) , ) , ) , ) P2P

P2P

(Distributed Hash Table DHT), -1 ( -) .

DHT , DHT -

1 (hash table hash map)

( - , , -) (.., )

(.., ).

5 . 2 P 2P 1 6 5

.

, ,

. DHTs

- , . - P2P Chord, CAN, Pastry

Tapestry.

5.1

( 200 ) - P2P -, , P2P

.

( : 30)

5.1

P2P

(); ( )

.

) P2P - .

) ,

P2P .

) P2P -.

) P2P ,

,

.

)

(hops) .

) P2P

P2P .

1 6 6 5 :

5.3 P2P

H - P2P .

Napster BitTorrent -, Gnutella

, , Pastry - P2P .

Napster

1999, Napster (Napster, 2012) P2P

. - , , - , , ,

. P2P

, ,

, - . Napster - ,

. ,

. , ,

(single point of failure)

. ,

(Recording Industry

Association of America RIAA) - -, , , Napster.

BitTorrent

BitTorrent (Pouwelse, Garbacki, Epema & Sips, 2005)

P2P 2001. - , 2009, 45-78%

P2P (~27-55% ,

) (Schulze & Mochalski, 2009). - (.torrent)

5 . 3 P 2P 1 6 7

, , .

- .torrent

. - , , ,

(tracker).

( BitTorrent)

(swarm) /

(seeds) (leachers).

, ,

.

BitTorrent - . BitTorrent - . ,

BitTorrent

, , , ,

. - BitTorrent DHT

, -, .

Gnutella

Gnutella (Ripeanu, 2001) P2P , - , . - Gnutella (

Gnutella) 2000.

,

(, , ,

). , - ( - , v0.4 ) - ...,

( 7). ,

5 ,

1 6 8 5 :

78.125 (=57) Gnutella.

, ,

. ,

, - ,

.

(

/),

v0.6 , - (leave)

(ultrapeer). . ,

,

, ,

, - -.

( ) - .

Pastry

To Pastry (Rowstron & Druschel, 2001) P2P ,

DHT. - (keys) (data items values)

()

( ). ,

()

.

, .

-

. , ,

. DHT - , (lookup

5 . 3 P 2P 1 6 9

(key)),

. ,

, ,

( SHA-1) , , lookup (key).

,

, .

, , lookup

(key) , ,

(Balakrishnan, Kaashoek, Karger, Morris & Stoica, 2003).

Pastry (ID),

. - 128-bit, 2b ( b=4,

). ,

,

ID . n L (leaf set), L 2 ID n, L 2 ID n.

, Pastry ,

, - ID . log2b N

(

) 2 1b - . i n ID i ID n i+1 .

, n - .

n ( ID - ), .

, , , - () ID . ,

n,

.

, -

1 7 0 5 :

log2b N . Pastry

.

Pastry (join protocol),

- (bootstrapping node) ID

.

5.2

(, ,

(overlay routing)); -; , , - Pastry. 150 .

( : 20)

5.2

1 Pastry , -

(ID) 9012.

myfile.txt, (

) 2315. - ( 100 )

, - .

1 7 1

P2P ,

, -

(

-). -

P2P

-

. ,

P2P P2P -

, , -

(, ) . , -

P2P ,

.

1 7 2 5 :

,

:

P2P ,

- -

P2P ,

P2P

(, ) P2P -

P2P Napster,

BitTorrent, Gnutella Pastry.

1 7 3

Androutsellis-Theotokis, S. & Spinellis, D. (2004). A Survey of Peer-to-Peer Con-tent Distribution Technologies. ACM Computing Surveys, 36(4), pp. 335-371. Doi:

10.1145/1041680.1041681

Balakrishnan, H., Kaashoek, M.F., Karger, D., Morris, R. & Stoica, I. (2003). Look-ing up Data in P2P Systems. Communications of the ACM, 46(2), pp. 43-48. Doi:

10.1145/606272.606299



Kang, C. (2011). Survey of Search and Optimization of P2P Networks. Peer-to-Peer

Networking and Applications, 4(3), pp. 211-218. Doi: 10.1007/s12083-010-0082-2

Kwok, Y.-K. (2011). Peer-to-Peer Computing: Applications, Architecture, Protocols

and Challenges. 1st edition. CRC Press

Lua, E.K., Crowcroft, J., Pias, M., Sharma, R. & Lim, S. (2005). A Survey and Com-parison of Peer-to-Peer Overlay Network Schemes. IEEE Communications Surveys

& Tutorials, 7(2), pp. 72-93. Doi: 10.1109/COMST.2005.1610546

Napster (2012). 15 2012, http://www.napster.

com/

Pouwelse, J., Garbacki, P., Epema, D. & Sips, H. (2005). The Bittorrent P2P

File-sharing System: Measurements and Analysis. Proceedings of the 4th Inter-

national Workshop on Peer-to-Peer Systems (IPTPS2005), pp. 205-216. Doi:

10.1007/11558989_19

Ripeanu, M. (2001). Peer-to-Peer Architecture Case Study: Gnutella Network. Pro-

ceedings of the 1st International Conference on Peer-to-Peer Computing (P2P2001),

pp. 99-100. Doi: 10.1109/P2P.2001.990433

Rowstron, A. & Druschel, P. (2001). Pastry: Scalable, Distributed Object Location

and Routing for Large-scale Peer-to-Peer Systems. Proceedings of the IFIP/ACM

International Conference on Distributed Systems Platforms (Middleware01), pp.

329-350. Doi: 10.1007/3-540-45518-3_18

1 7 4 5 :

Schulze, . & Mochalski, . (2009). Internet Study 2008/2009.

15 2012, http://www.ipoque.com/sites/default/files/mediafiles/

documents/internet-study-2008-2009.pdf

Shen, X., Yu, H., Buford, J. & Akon, M. (2009). Handbook of Peer-to-Peer Network-

ing. Springer

1 7 5

Kang, C. (2011). Survey of Search and Optimization of P2P Networks.

Peer-to-Peer Networking and Applications, 4(3), pp. 211-218. Doi: 10.1007/s12083-010-0082-2. , ,

P2P .

,

. P2P

- .

Shen, X., Yu, H., Buford, J. & Akon, M. (2009). Handbook of Peer-to-Peer Networking. Springer. , , -, P2P -. -, P2P ,

, , - (Service-Oriented Architectures SOA),

, P2P, P2P ..

1 7 6 5 :

5.1

) . P2P - ( ) . - (.. )

,

.

) . , P2P - (),

.

) . -

, , , - .

) .

,

, - / .

) . - - (hops) -. , ,

, ,

.

) .

- , - P2P -.

1 7 7

, !

P2P . , -

P2P -

/

P2P

5.1 5.2.

5.2

- lookup (2315)

1 ID:9012.

N2=2067, N

3=2300, N

4=2312 N

5=2315 ( ).

, N2 1

1, N

3 2

2 ...

5, ,

,

4.

,

Pastry. , -

5.3 , -

Pastry, 10 -

Coulouris et al. (2011).

1 7 8 5 :

5.1

P2P :

+ (

).

+ ( - ).

, / /

.

(single point of failure), - .

P2P :

+ , -, -.

( - , , ).

, -.

P2P :

+ -.

+ ,

, , .

+ ,

.

, -.

1 7 9

,

(, ).

P2P :

+ , - .

P2P ( - ).

.

.

, , -

P2P . , -

5.2 , 3

Androutsellis-Theotokis & Spinellis (2004).

5.2

/

/ .

,

- . ,

IP ,

()

(.. IDs Pastry ).

, (-)

( ),

. , (hop) - Pastry /- .

1 8 0 5 :

. -

, ! ,

5.2 5.3 , 10

Coulouris et al. (2011).

1 8 1

B

Byzantine failure ( ): o - - (.. - , ,

).

C

Centralized P2P systems ( ): P2P - - .

Clock synchronization ( ): - ,

-, , .

Concurrency transparency ( ): - ()

, .

Consistency protocol ( ):

,

(.. ).

D

Directory service ( ):

, - ( , ..

1 8 2 :

), - .

Distributed Hash Table DHT ( -):

. (, ) -

.

Distributed Operating System ( ):

- , - .

Distributed system ( ): - , - .

Domain Name Service DNS ( ):

IP .

Drift (): ,

.

F

Failure transparency ( ):

, - ,

.

GGlobal clock ( ): - .

1 8 3

H

Hybrid P2P systems ( ): P2P

, - (supernodes super peers).

I

Intero

Documents

sdy50_b