distributed object based system

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 1/11

1

2

Distributed Document-BasedSystems

Chapter 11

3

4

5

6

The World Wide Web

Overall organization of the Web.

1

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 2/11

7

8

Document Model (1)

A simple Web page embedding a script written in JavaScript.

9

10

Document Model (2)

An XML definition for referring to a journal article.

11

Document Model (3)

An XML document using the XML definitions from previous slide

12

Document Types

Six top-level MIME types and some common subtypes.

2

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 3/11

13

14

Architectural Overview (1)

The principle of using server-side CGI programs.

15

Architectural Overview (2)

An HTML document containing a JavaScript to be executed by the server

16

Architectural Overview (3)

Architectural details of a client and server in the Web.

17

18

HTTP Connections

a) Using nonpersistent connections.

b) Using persistent connections

3

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 4/11

19

HTTP Methods

Operations supported by HTTP.

20

HTTP Messages (1)

HTTP request message

21

HTTP Messages (2)

HTTP response message.22

HTTP Messages (3)

Some HTTP

messageheaders.

23

  24

Clients (1)

Using a plug-in in a Web browser.

4

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 5/11

25

Clients (2)

Using a Web proxy when the browser does not speak FTP.

26

27

Servers

General organization of the Apache Web server.28

Server Clusters (1)

The principle of using a cluster of workstations to implement a Web service.

- horizontal distribution -

29

Server Clusters (2)

(a) The principle of TCP handoff.30

Server Clusters (3)

(b) A scalable content-aware cluster of Web servers.

5

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 6/11

31

32

Uniform Resource Locators (1)

Often-used structures for URLs.

b) Using only a DNS name.

c) Combining a DNS name with a port number.

d) combining an IP address with a port number.

33

Uniform Resource Locators (2)

Examples of URLs.

34

Uniform Resource Names

The general structure of a URN

35

36

6

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 7/11

37

Web Proxy Caching

The principle of cooperative caching38

39

Server Replication

The principle working of the Akami CDN.40

41

42

Security (1)

The position of TLS in the Internet protocol stack.

7

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 8/11

43

Security (2)

TLS with mutual authentication.44

Distributed Coordination-BasedSystems

Chapter 12

45

Introduction to Coordination Models

A taxonomy of coordination models (adapted from[cabri.g2000]) 46

47

48

8

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 9/11

49

Overview of Jini

The general organization of a JavaSpace in Jini.50

51

Architecture

The layered architecture of a Jini System.

52

53

Communication Events

Using events in combination with a JavaSpace54

9

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 10/11

55

Processes (1)

A JavaSpace can be replicated on all machines. The dotted lines show thepartitioning of the JavaSpace into subspaces.

b) Tuples are broadcast on WRITE

c) READs are local, but the removing of an instance when callingTAKE must be broadcast

56

Processes (2)

Unreplicated JavaSpace.

b) A WRITE is done locally.

c) A READ or TAKE requires the template tuple to bebroadcast in order to find a tuple instance

57

Processes (3)

Partial broadcastingof tuples andtemplate tuples.

58

59

The Jini Lookup Service (1)

The organization of a service item.

60

The Jini Lookup Service (2)

Examples of predefined tuples for service items.

10

8/4/2019 Distributed Object Based System

http://slidepdf.com/reader/full/distributed-object-based-system 11/11

61

62

63

Synchronization of Transactions

The general organization of a transaction in Jini. Thick lines showcommunication as required by Jini's transaction protocol 64

65

66

Security

The position of PAM with respect to security services.

11