Failure Recovery of Composite Semantic Web Services using Subgraph Replacement

religiondressInternet and Web Development

Oct 21, 2013 (3 years and 5 months ago)

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Failure Recovery of

Composite Semantic Web Services

using Subgraph Replacement

Hadi

Saboohi

Amineh

Amini

Hassan
Abolhassani


Karaj Islamic Azad University, IRAN

Web Services

15

May
2008

ICCCE’
08

2


A software system designed to support interoperable
Machine to Machine interaction over a network


Web APIs

Semantic Web

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May
2008

ICCCE’
08

3


Extension of current web


Giving well
-
defined meaning to information


Enabling computers and people to work in cooperation


Semantic Web Services

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May
2008

ICCCE’
08

4


Semantically marked
-
up software resources that can be
published, discovered, composed and executed across the
Web in a task driven semi
-
automatic way


Dynamic part of the semantic web

Semantic Web Services, continued

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May
2008

ICCCE’
08

5

Interoperable

Syntax

Interoperable

Semantics

Dynamic

Resources

Static

Resources


Web Services


WWW

Semantic

Web Services


Semantic Web

Service Broker

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May
2008

ICCCE’
08

6

Service Broker

Service Requester


Service
Registry


Concepts
Registry


Ontology
Cache


Composed
Services

Cache


Registry
Manager


Ontology
Manager


Composer


Adapter


Matchmaker


Executor


Kernel


Service Providers

Ref.
4

Modeling Composite Semantic Web Services

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May
2008

ICCCE’
08

7


Directed Acyclic Graph


Nodes: Web Services


Edges: Services inputs and outputs


I, P


A

S
i


B

O, E

O
A
,
E
A

I
Si
,
P
Si

O
Si
,
E
Si

I
B
,
P
B

Execution problem of a composite semantic
web service

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May
2008

ICCCE’
08

8


Execution of whole process depends on well
-
execution of
all sub
-
processes


In execution failure of any constitutive web service, failure
recovery is a better solution


Our approach


Replace a sequence of web services containing failed service in
case a “same skilled” one is not exists

Replacement Strategy

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May
2008

ICCCE’
08

9


Responsible for:


Finding best substitution alternative


Managing differences between old and new service(s)


Replacement Steps

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2008

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08

10

1.
Finding all possible alternatives

a.
Subgraph calculation

b.
Alternative search

2.
Ranking alternatives

3.
Replacement

1
. a. Subgraph calculation

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May
2008

ICCCE’
08

11

A

S

B

A

S

B

A

S

A

S

B

S

B

Composite Graph

All possible subgraphs

1
. b. Alternative search

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May
2008

ICCCE’
08

12


Search for compatible replacement alternatives


Compatibility


Functional attributes (Inputs, Outputs, Effects and
Preconditions)


Non
-
functional


Response time


Availability


Reliabiity


Cost





2
. Ranking alternatives

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May
2008

ICCCE’
08

13


Each constitutive web service may exist in more than one
subgraph


For example:
S

is in four subsets of subgraphs ({
S
}, {A,
S
}, {
S
,B},
{A,
S
,B})


Each subgraph may have several alternatives


3
. Replacement

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2008

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08

14


First: re
-
execution attempts


Second: Replacing best ranked subgraph


Compensation of well
-
executed web services in old subgraph

Replacement Patterns

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2008

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08

15


Managing differences between old and new subgraphs


New subgraph may have additional IOPE(s) than old one
and vice versa


Prepare required inputs and preconditions


Mark the composite as non
-
optimized and inspect to execute
without additional outputs and effects

Conclusion and Future Works

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May
2008

ICCCE’
08

16


Alleviate failure of software systems (CSWS)


Replacing a sequence of web services


Using forward and backward mechanisms


Heuristic algorithms to decrease number of subgraphs


Extend for all composition graphs