2011 5th Malaysian Conference in Software Engineering (MySEC)

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978-1-4577-1531-0/11/$26.00 ©2011 IEEE

A Systematic Literature Review of Interoperable Architecture for E-Government Portals

Khairul Anwar Sedek Faculty of Computer and Mathematical Sciences

Universiti Teknologi MARA 02600 Arau, Perlis, Malaysia

khairulanwar@perlis.uitm.edu.my

Shahida Sulaiman1,2, Mohd Adib Omar1 School of Computer Sciences1

Universiti Sains Malaysia 11800 USM Pulau Pinang, Malaysia.

Faculty of Computer Science and Information Systems2 Universiti Teknologi Malaysia

81310 UTM, Skudai, Johor, Malaysia. shahidasulaiman@utm.my, adib@cs.usm.my

Abstract— One of the roles of e-government portals is to provide a one-stop service to users. In order to fulfill this role, it requires collaboration with other government agencies and businesses to provide an effective one-stop center for users to access and perform various services. Current e-government portals are mostly lack of interoperability whereby users still need to access government services from various portals or websites. Interoperability is a technical requirement to achieve government services collaboration and integration. There are many challenges and approaches to achieve better interoperability in e-government portals. Architecture-based and model-based approaches are essential research areas that can improve interoperability starting from the planning stages. Architecture provides overall overview of e-government components and relationship between components. This paper systematically reviews current architecture-based approaches to find a suitable approach and its requirements to produce a better architecture for e-government portal based on the lessons learned from the previous works.

Keywords-Systematic literature review; Software Architecture; E-government Portal; Interoperability

I. INTRODUCTION

E-government portal becomes an important medium as a one-stop centre for the public to access government services. Most developed countries such as Republic of South Korea, United States, and Canada are in top rank of e-government achievement [1]. They have state-of-the-art of e-government portal technology that provides high-quality services to citizens and contributes significantly to their success [2], [3].

The main barrier that contributes to the failed e-government projects is integration barrier. The integration barriers include lack of architecture, incompatible data standards, lack of relevant integration expertise, and the existence of legacy process [4]. According to Shaw [5], “software architecture is the principled study of the overall structure of software system, especially the relation among subsystems and components”. Furthermore, Shaw stresses that software architecture is an area that must be refined and improved in order to produce a better software system. Architectural descriptions provide skeleton of a system properties and describe the system capabilities according to system requirements. Therefore, study in e-

government architecture is a very important area because it can improve the overall structure of complex integration and interoperability of e-government system.

One-stop e-government portal requires integration and interoperability with various departments, public organizations, and private organizations. They use variety of systems, platforms, data formats, procedures, and protocols. Furthermore, e-government portals that provide multi type of e-government services are required. The multi type of e-government portals includes Government to Citizen (G2C), Government of Government (G2G), Government to employee (G2E), and Government to Business (G2B) [6] in one-stop service centre. These requirements make integration of e-government services in one-stop portal a very tedious and complex task. They require proper planning and strategy to achieve better results.

This paper focuses on the study of current e-government portals by looking into the details of the architecture of e-government portals. This is to learn from the architecture on ways to improve e-government portals especially in terms of interoperability. Unlike the previous works [7–9], this study investigates the architectural style, quality attributes, and achievement towards higher interoperability level using systematic literature review (SLR) [10].

The objectives of this paper are:

1) To summarize the existing works towards improving interoperability of e-government portals in the context of architecture.

2) To identify the strengths and limitations of current e-government architecture in order to suggest areas for further research.

The remaining five sections are as follows. Section II presents the related works to this paper. Section III explains the review process followed in this study. Section IV reports research results. Section V explains the discussion of research results and finally in Section VI concludes and outlines some possible future works.

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II. RELATED WORKS

Ouchetto et al. [7] analyse five e-government architecture and frameworks including EOSG (Europe), eSDK (UK), FEA (US), EIP, and eAI. The study investigates the availability of eight e-government portal features. The features include inter-authorities integration, legacy system integration, evolutionarity, access type, back-office, architecture orientation, and technology and standards.

Guijarro [8] surveys interoperability framework and enterprise architectures of e-government portals in Europe and United States (US). The study focuses on interoperability policy and its implementation in the frameworks and enterprise architectures. Enterprise architecture in Europe is a high-level architecture consists of four levels. Enterprise architecture in US produces Federal Enterprise Architecture Framework (FEAF) based on Zachman Framework. The study investigates three selected architectures only. It does not provide the overall descriptions and analysis for larger number of architectures.

Helali et al. [9] review seven e-government architectures from developed countries. The work analyses the availability of intrinsic and extrinsic characteristic of e-government architecture. The quality attributes that have been applied to all architectures are interoperability and integration, security and trust, and compatibility. The study reports that a few architectures considering cost, scalability and legality in the architecture of portals. However, the study does not evaluate the quality of the architecture.

Unlike the previous works, this paper explores the architectural structures and elements of e-government portals and analyses their achievements towards a high level of interoperability. This enables us to evaluate the strengths and weaknesses of the present approaches and discover the area of the current approaches that can be improved.

III. REVIEW PROCESS

The review processes follow the SLR guidelines for software engineering by Kitchenham [11]. The guidelines have three main phases: review planning, review execution, and review reporting phase. The following sub-sections explain the review planning phase. This phase consists of research questions, search strategy, selection criteria, and qualitative analysis.

A. Research Questions

The criteria for identification of research questions are population, intervention, comparison, outcomes, and context. Table I shows the criteria and scope of research question structure.

Based on the research question structure as shown in Table I, the research questions are:

� How many researches propose architectural approach for e-government portals and when is the earliest and the latest study?

� What are the important characteristics of architectural aspect of e-government portal?

� How far the interoperability and reliability achievements of the current architecture of e-government portal?

� What are the common flaws and strengths of the existing e-government architectures?

Table I. Structure of research question

Criteria Scope

Population Papers propose e-government architecture portal.

Intervention Approaches that address issues in interoperability.

Comparison Limitation and strength of each approach.

Outcomes Suggest improvement area of existing approach.

Context Architecture for e-government portal

B. Search Strategy

This study uses iterative search strategy that consists of the following steps:

1) Preliminary search in major indexing databases: Use initial keywords such as “e-government portal”, “e-government architecture”, and “e-government portal architecture”. The objective of this stage is to test and refine the search keywords.

2) Research in major indexing databases: Use refined keywords. The refined keywords are “e-government AND architecture AND portal.” The major indexing databases are Google Scholar, ScienceDirect, ISI Web of Knowledge, ACM Digital Library, SpringerLink, and CiteseerX.

3) Record search results. 4) Classify papers according to types of publications:

They are journals, conferences, theses, technical magazines, book chapters, technical book, reports, and web pages.

C. Selection Criteria

This step ranks the source of papers from highest to lowest priority: journals, conferences or proceedings, technical reports, thesis reports, and books. The reviewed papers are mainly in English. Other languages will also be reviewed if they can be translated into English using an automatic translator such as Google Translate software. The subjects covered are software engineering and computer sciences. The papers should explicitly contain text that attempts to define, propose, suggest, or describe an architectural approach for e-government interoperability.

D. Qualitative Analysis

The tabulation of data synthesis involves collating and summarizing the results of the included primary studies. Information from the study (such as intervention, population, context, sample sizes, outcomes, and study quality) in a manner that is consistent with the review questions. Appendix I shows the summary of the analysis for e-government portal architectures. It highlights similarities and differences in the outcomes of the study.

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Each column has the following architectural characteristics:

� Year of the publication.

� Extended Level of Conceptual Interoperability Model (LCIM) [12]: This model has the interoperability level from level 0 to level 6 as shown in Fig. 1.

� Type of e-government: The types of e-government include G2G, G2B, G2E, and G2C [6]. The architecture supports this type of e-government portals.

� Integration maturity level: This is based on Layne and Lee’s model as shown in Fig. 2 [13]. The evaluation of the paper is based on the complexity and level of integration involved as shown in the architectures.

� Architectural style or architectural patterns: This is a description of elements and relation types together with a set of constraints on how they may be used [14].

� Quality attributes: This determines quality attributes of architecture including usability, modifiability, performance, correctness and completeness, and buildability [14].

Figure 1. The extended LCIM [12]

Figure 2. The Layne and Lee’s dimension and stage of e-government

development [13]

IV. RESULTS

Appendix I shows results of the search procedure. There are seventeen unique works selected from 8,368 articles. The selected papers met the criteria as defined in the Section III.C. The selected papers are those that proposed new or enhanced approaches or techniques of architectures for e-government portal. The earliest study is in year 2005. There is only one published research in 2001. In 2004, the number of research increased to two, two researches in year 2005, four in 2007, three in 2008, two in 2009, three in 2010 and one in 2011. It shows that there is no significant increase in the number of research.

In term of e-government type, most architectures implement G2G and G2C. Only six out of seventeen architectures support G2B and only two architectures support G2E. Therefore, the most implemented e-government type is G2C. Five e-government portals provide one-stop portal.

Table II shows the achievement of e-government portal in the LCIM level. There are nine proposed architectures (53%) that achieve level 2. The rest shows that seven at level 3, one at level 4, and no e-government portal at level 0, 1, 5, and 6. TABLE II. EVALUATION OF THE LCIM LEVEL OF E-GOVERNMENT

PORTAL ARCHITECTURE

LCIM Level 0 1 2 3 4 5 6 Number of architectures 0 0 9 7 1 0 0

Table III shows the achievement of the proposed architecture in the level of integration maturity. About 25% or four architectures achieve vertical integration. The rest of the architecture, 13 architectures achieves horizontal integration. It is the highest maturity level of integration. No architecture found in catalogue and transaction level.

TABLE III. LEVEL OF INTEGRATION MATURITY OF E-GOVERNMENT PORTAL ARCHITECTURE

Integration maturity

Catalogue Transaction Vertical integration

Horizontal integration

Number of architectures 0 0 4 12

Most architecture (59%) adopts SOA or Web service. The rest adopt e-GIF, EAI, GML, and proprietary architecture. Only one uses unknown architecture. In addition, the previous works address the quality attributes that are security, reliability, usability, and performance. City One-stop Portal is the only one architecture that addresses all of these attributes [15]. Security is the attribute that mostly addressed in the architecture, which is 47%, or eight architectures.

V. DISCUSSIONS

This section answers the research questions.

A. How many researches propose architectural approach for e-government portal and when is the earliest and the latest study?

This study includes seventeen unique researches that propose architectural e-government portal. The earliest study is

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in the year 2001 [16] and the latest study is Service Oriented Travel Portal [17]. The earliest architecture employs basic HTTP architecture, web services and enterprise application integration (EAI). The latest work [17] employs SOA in the portal architecture. The existing work proposes the concept of one-stop portal since 2001 [16].

B. What are the important characteristics of architectural aspect of e-government portal?

Various characteristics of e-government portals are identified from previous works since the year 2001. Below are significant architectural characteristics of e-government portals.

� SOA, EAI, and layered architectures are the common architectural style in e-government portal [18], [19]. The architectures are defined in several perspectives, such as global architecture, service architecture, and a detailed architecture [19], [20].

� Business process engine is an enabler for dynamic and interoperable service integration and fully automatic processes [21]. Implementation of semantic Web service technology can improve interoperability by utilizing it higher semantic expressiveness [19].

� To ensure better interoperability especially in one-stop e-government portals, the respected countries should comply with the e-government Interoperability framework (eGIF) [22].

� The architectures incorporate mediators to resolve semantic or technical mismatches during interaction between services [19] using a suitable approach such as Semantic Mediator Model and User Ontology to improve integration in distributed environment [23].

� Consumer are allowed to add or remove services based on the specified criteria such as price, reliability, security, credit, or weighted performance utilities [17].

� A service search engine is required to select emerging Web services and automatically across the Internet [17], [24].

� The architectures should be customizable to support evolving user’s service requirements and government policies through portlet approach as an example [15].

� Requirements for generic one-stop e-government architectures are client-centred approach, channel multiplicity, concurrent access point, versatility, security, life events, normalized services, heterogeneity, entity authorization, and standard evolution [25]. Small and medium size e-governments face special issues and challenges in interoperability, scalability, security and trust, and transparent services because they have limited cost considerations [26].

SOA, one-stop portal service centre, semantic web services, integrated and interoperable e-government, and layered architecture are the most common current e-government architecture. However, there are some significant idea that can distinguish the ordinary e-government portal to a better one

such as providing users with freedom and autonomy to manage their own related services based on their needs and wants.

C. How far the interoperability and reliability achievements of the current e-government portal architecture?

This paper examines the interoperability level based on the extended LCIM [12] and integration maturity model [13]. The evaluation results in LCIM achievement are available in Table II. Most works achieve level two and three. System in level two has syntactic interoperability where there is a common data format in order to exchange messages. In level three, the system achieves semantic interoperability where they know the meaning of data or message exchange. Not a single e-government portal architectural work achieves level four, five and six. In the level four, the system reaches pragmatic interoperability where systems involve in the integrated system understands the process and the workflow employed in the transaction. There is no evidence that shows the latest architecture achieves a higher LCIM level.

Table III shows the achievement of integration maturity of e-government portal architecture. The research result is as in Appendix I. Four works achieve vertical integration, 12 works in horizontal integration and no single project falls lower than this level of integration stage. Generally, most works reach horizontal integrations where at this stage the architecture is able to achieve a true integrated and interoperable portal across different functions and organizations in a one-stop portal service centre.

Only five works claim they address reliability issues. However, the number is smaller if the evaluation is based on the actual reliability definition. Web application reliability should focus on prevention or reduction of Web failures [27]. The quality of a system should be better if can be introduced earlier during analysis and design.

D. What are the common limitations and strengths of the existing e-government architecture?

The overall discussions show that the current works achieve better e-government approaches that fulfil current users’ requirements. For example, they are able to produce a one-stop portal, integrated, secure, reliable and easy to use. The ability of a few works that support G2G, G2B, G2E, and G2C type of e-government is one of the high achievements in this study. However, there are some weaknesses in the current works that can be refined and improved to fulfil current and future users’ needs and wants. Examples of users’ needs and wants are [28–30]:

� User-centricity.

� Real-time, accurate, reliable, and easy to use.

� Provide customized and manageable services.

� Green government.

� Simplification of e-service usage and administrative procedure.

Most e-government architectures achieve horizontal or vertical integration; however, most works achieve up to level 3

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of LCIM. This shows that most works achieve higher integration maturity but not in the area of interoperability. Producing a higher level of interoperability and reliability will fulfil current users’ needs and wants. They want fast and one-stop centre e-government service centre. The lesson learned from this study will be able to provide the elements to be included in the development of architecture for e-government portal such as how it should be structured and how it should be connected to various external and internal services.

Most recent e-government architectures adopt SOA. However, those reviewed architectures do not have detail descriptions including the structural properties and extra-functional properties [31]. Additionally, the descriptions of the architectures should be in multiple views such as the logical view, the development view, the physical view, and the process view [32]. A complete and detailed architecture will ease the development and implementation of a system and integration of among systems.

VI. CONCLUSION AND FUTURE WORKS

There is no single architecture showing how the architecture can help users to manage services. The services are adding, removing, monitoring, and scheduling service executions, which have relation according to their needs and wants. This will give freedom to users in managing their own services and perform the trusted services on the Web. Furthermore, current works are lack of the architecture towards a high level of interoperability and reliability. Our future research is to formulate an architecture for e-government portals that is able to fulfil above requirements. To achieve this vision, it requires the use of a systematic formulation and a right approach to produce an architecture that can achieve a high level of interoperability and reliability.

ACKNOWLEDGMENT The authors would like to acknowledge Postgraduate Incentive Grant, 1001/PKOMP/821112 that supported the Writing Workshop (WRiTe 2) as the platform to produce this paper.

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APPENDIX I: SUMMARY OF EXISTING RESEARCHES IN E-GOVERNMENT ARCHITECTURE

Type of portal Year LCIM level

E-government type

Integration Maturity level

Architectural style Quality attributes

Technical architecture of service-oriented one-stop travel portal [17]

2011 3 G2C, G2B Vertical SOA Security, Usability

SOA-based e-government [18] 2010 2 G2C, G2G Horizontal SOA N/A Content-oriented e-government portal [33] 2010 2 G2C Vertical N/A Usability SemanticGov Architecture (Pan-European) [19] 2010 3 G2C, G2E,

G2G, G2B Horizontal Semantic Web

service N/A

City One-top Portal [15] 2009 2 G2C, G2G, G2B

Horizontal SOA Security, Reliability, Usability, Performance

eGIF architecture for one-stop e-government service (Greek) [22]

2008 3 G2C, G2G, G2B

Horizontal eGIF architecture Security, Reliability, Usability

Integration of distributed e-government [23] 2008 3 G2C, G2G Horizontal SOA with ontology Security E-Government Planning Portal [34] 2008 3 G2G, G2C Vertical Semantic Web

service N/A

Demand-driven e-government [20]

2007 3 G2C, G2E, G2G

Horizontal SOA Security, Reliability, Usability

Secure e-government architecture (Tunisia) [35] 2007 2 G2C, G2G

Horizontal SOA Security, Reliability, Usability

Distributed architecture for one-stop e-government [25]

2007 2 G2C, G2G Horizontal Distributed Web service architecture

Security, Performance

Layered architecture for pragmatic e-government [21]

2007 3 G2C, G2G Horizontal SOA Security

Secure SMPO e-government [26]

2005 2 G2G, G2C, G2B

Horizontal SOAP-based Web service

Security, Usability, Low cost

Enterprise Architecture Integration (EAI) in E-Government [36]

2005 2 G2C, G2G, G2B

Horizontal EAI Reliability, Usability

Workfair Portal [24] 2004 2 G2G, G2C Vertical SOAP-based Web service

Usability

Web portal architecture for collaborative intra-government planning [37]

2004 2 N/A N/A Proprietary Semantic Web architecture

N/A

One-stop e-government portal architecture [16] 2001 2 G2C, G2B, G2G

Horizontal Client server Web architecture

Usability