architecture - complete.doc.doc.doc
DESCRIPTION
TRANSCRIPT
Introduction
This document covers the following:
Brief description of the project, context, business goals, and constraints for
the system being developed.
Requirements and prioritized utility tree.
Architecture presented by various architectural viewtypes.
Architecture trade-off analysis based on architectural alternatives.
This document is intended for the following audience:
Stakeholders of the ZEN Tool Project: client, mentors, and development
team.
Those who want to understand the architecture of the ZEN Tool.
Every image with the icon represents an image which maps to other architectural
views.
[edit] Project Overview
[edit] ZEN Tool
The ZEN Tool Project is sponsored by the Integration of Software Intensive Systems
(ISIS) initiative at the Software Engineering Institute (SEI). The intention of the
project is to automate a portion of the Service Migration and Reuse Technique
(SMART) that helps organizations analyze legacy systems to determine whether
their functionality, or subsets of it, can be reasonably exposed as services in a
Service-Oriented Architecture (SOA). The portion that needs to be automated is the
data collection process guided by the Service Migration Interview Guide (SMIG).
The process is currently manual and time-consuming. With the tool support, SEI
expects to see some fundamental improvement on efficiency and quality when they
conduct SMART engagements.
[edit] Business Goals
Author's note: this set of goals was used for quality attribute workshop.
This tool should reduce the cost of SMART interviews in terms of time by at
least one day.
This tool should reduce the cost of SMART analysis (creating reports) in
terms of time and effort by presenting the data in a useful and efficient way for
the SEI personnel to use.
This tool should improve the capability of the SEI to generate a SMART
"Standard", which would improve market awareness of the technique, thus
expanding the market of potential users for the SMART technique.
This tool should improve the market's reception of the SMART technique via
improving the market's perception of the technique's formality.
[edit] Business Context
This view defines the context of the system during normal operation and
maintenance.
Related use cases can be found in Use Case View section.
Related quality attribute scenarios can be found in Quality Attributes section.
[edit] Constraints
The following constraints are applied to the design of the architecture.
[edit] Business Constraints
← SMART Engagements involve SEI personnel traveling to client locations and
performing interviews. Data taken in these engagements must be consolidated
into a central repository.
← The SMART team has no budget for commercial software; any third-party
software must be free.
[edit] Technical Constraints
← Java will be the language used. The advantage in writing the code in Java is
portability. There is no dependency on the operating system, either during the
development process or during deployment. Java has been chosen for the
purpose of maintainability as well. The SEI staff is comfortable using Java.
← The ZEN Tool will need to work on a Windows XP machine.
← Connection to SEI requires using virtual private network (VPN).
Requirements Overview
[edit] Use Case View
The functional requirements are presented using a use case model.
Detail information can be found in Use Case Specification.
This use case model shows the allocation of requirement between roles (aka,
actors).
The relation between roles is generalization. SMART Member is a generalization of
Interview, Analyst and Administrator.
Key: UML
Use Case Catalog
Use Case Name
Description
Sign In SMART Member needs to sign in the system before performing any other operations.
Sign Out SMART Member can sign out from the system during any give time.
Acquire Engagement Data
Prior to any interview phases of a given engagement, the interviewer obtains a copy of the engagement setup data prepared in the Setup Engagement Data use case.
Choose Question
During an interview, the interviewer chooses a question in the system as the focus of the discussion. The interviewer browses through the categories of topics, and from which a desired question is located. To quickly locate a question, the interviewer can enter keywords and instruct the system to search the matching questions. The interviewer can also follow a predefined sequence of questions that facilitates a smoother interview session.
Record Answer
During an interview, the interviewer records annotations to a selected question. The possible types of annotations include predefined answers, comments, and tags. One possible predefined answer can be "not-applicable". For the purpose of status, a question is considered to be "answered" if one of two mutually exclusive conditions are met. First, if there are one or more predefined answers associated with a particular question, then the question is considered to be "answered" if and only if at least one of the predefined answers has been selected or a comment has been entered. Second, if there are no predefined answers associated with a particular question, then the question is considered to be "answered" if and only if there is a comment entered for that question. A question may be annotated with one or more tags, but applying tags has no effect on the question's "answered" status. The purpose of the tags is for generating templates (Authors' note: Should we distinguish answer from annotation?)
Consolidate Interview Data
After each interview phase of a given engagement, the interviewers submit their individual interview data for consolidation. Each interviewer associated with a specific engagement is expected to upload the data they took, however this is not mandated. Once at least two sets of data has been submitted, anyone of the interviewers can explicitly trigger the consolidation. This consolidated interview data can then be obtained by the interviewers.
Generate Report
This use case applies to two circumstances: First, during an engagement, the analyst instructs the system to generate reports based on interview data collected so far. The analyst first chooses a report type, such as Current SMIG or Migration issues table, and then the system generates the report. Second, in between engagements, the analyst instructs the system to generate reports based on historical engagements. The analyst selects one report type, such as Draft of final report or List of questions per tag, and then the system generates the report accordingly.
Generate Template
Analyst generates two kinds of templates: service table or component table. The format of the templates must be editable. The preferred format is xls but csv is also acceptable. The system is given the templates that are used during interview, and then the system adds new columns to them. The columns are the short names of questions marked with specific tags.
Setup Engagement Data
Administrator prepares an engagement by entering information obtained prior to an engagement. The information includes the engagement client organization, type of system under evaluation, profiles of interviewees, the version of the SMIG which will be used, and the set of tags that will be used.
Update SMIG Information
Administrator updates SMIG information. It includes the basic create, read, modify and delete operations. The administrator can also promote the updated SMIG into a new version. The system has to keep the old versions of SMIG in order to maintain data consistency for old engagement data.
Update Tag List Administrator updates the default tag list, which is used during Setup Engagement Data. It includes the basic create, read, modify, and delete operations.
Register User Account
Administrator registers user account, which can be used in the Sign In use case. Additionally, administrator can modify, delete and reset user account.
[edit] Quality Attributes
The following quality attributes, represented with the utility tree, drive the design of
architecture.
The quality attribute scenarios in a six-part format can be found in Six-Part Quality
Attribute Scenarios section.
This table is derived from quality attribute scenarios.
Each quality attribute scenario is ranked with importance (I) defined by the client,
and estimated level of difficulty (D). Both values are based on a scale of high(H)-
medium(M)-low(L).
Color scheme:
← Red: High importance scenarios with high level of difficulty.
← Yellow: High importance scenarios with low to medium level of difficulty.
Attributes Concerns Scenario# Description
Rank
(I, D)
Reliability Data integrity #1
At the end of an interview day, the system generates a consolidated report based on the input data of three team members that shows the risk factors that reflect correctly what was captured.
(H, L)
Usability Smartness #2 When a report is generated, then the report includes risks based on historical data.
(L, H)
Modifiability Flexibility #3 When Dennis, a non-technical person, generates a report, he can specify the information printed within 10 minutes.
(M, M)
Usability Input correctness
#4
Entering New SMIG information (offline)
← Question
← Answers
← Risk factor
← Recommendation
← Related questions
← Category
can be entered consistently and that the tool provides
hints when inconsistent inputs are received. The
process should be termed complete only when all
inconsistencies have been resolved.
(H, M)
Usability User's mental model
#5 When entering a new thought-about SMIG question, Dennis will find and enter the question in the right place in not more than 5 minutes.
(M, H)
Usability Navigation #6
Client provides information not related to current question, the person using the tool will navigate to the related topic within 15 seconds and then be able to return to the previous question with one push of button.
(H, L)
Modifiability Flexibility #7 A developer is able to add the generation of the migration issue template within 1 person-week effort.
(H, M)
Modifiability Flexibility #8 A developer will be able to add a new risk analysis capability reflected in report with only changing 1 component.
(M, H)
Modifiability Flexibility #9 A developer will be able to add new fields specific to a question or an engagement via modifications to the GUI within 2 person-days per field.
(M, H)
Modifiability Flexibility #10 A developer will be able to create new specified report type within 5 person-days
(H, M)
Security Integrity of SMART process
#11 Unauthorized access to the application, and all these attempt are recognized and denied.
(H, M)
Security Integrity of SMART process
#12 Unauthorized access to the data in to database and all such attempts are recognized and denied.
(H, M)
Security Integrity of SMART process
#13 Eavesdropping on any communications is not possible based on current technical standard.
(H, L)
Performance UI Response Time
#14 During the interview, the status will be updated within 1 second of a change occurring.
(H, L)
Availability Robustness #15 During an interview, the interview module will be available at 99.9%.
(M, H)
Availability Downtime #16 In the event of a system crashes, the application will return to former state within 30 seconds from application start.
(H, H)
Usability Intuitiveness #17 While entering information to a question, this question can be tagged with multiple tags in less then 1 second per tag
(H, L)
[edit] Six-Part Quality Attribute Scenarios
Quality Attribute Scenario #4
Stimulus: Administrator enters new SMIG information
Source of Stimulus:
Administrator
Environment: At runtime
Artifact: ZEN Server
Responses: New SMIG information can be entered consistently and that the tool provides hints when inconsistent inputs are received. The process should be termed complete only when all inconsistencies have been resolved.
Response Measure:
Inconsistent inputs are rejected with hints showing where the inconsistency is.
Quality Attribute Scenario #6
Stimulus: Client (interviewee) provides information not related to current question
Source of Stimulus:
The person using the tool (interviewer)
Environment: At runtime
Artifact: ZEN Client
Responses: Navigate to the related topic and then be able to return to the previous question
Response Measure:
Navigate to the related topic in 15 seconds; return to the previous question with one push of button
Quality Attribute Scenario #7
Stimulus: A developer wishes to add the generation of the migration issue template
Source of Stimulus:
Developer
Environment: At design time
Artifact: Migration issue template
Responses: Locates the migration issue template; makes modification; tests modification; deploys modification
Response Measure:
Within 1 person-week effort.
Quality Attribute Scenario #10
Stimulus: A developer wishes to create new specified report type (template)
Source of Stimulus:
Developer
Environment: At design time
Artifact: Report type (template)
Responses: Locates the report type (template); makes modification; tests modification; deploys modification
Response Measure:
Within 5 person-days
Quality Attribute Scenario #11
Stimulus: Tries to access the application
Source of Stimulus:
Internal or external individual who are not authorized
Environment: At runtime
Artifact: ZEN Client and ZEN Server
Responses: All these attempts are recognized (recorded) and denied
Response Measure:
TBD (Time/effort/resources required to circumvent security measures with probability of success)
Quality Attribute Scenario #12
Stimulus: Tries to access the data in the database
Source of Stimulus:
Internal or external individual who are not authorized
Environment: At runtime
Artifact: ZEN Client
Responses: Stores data in unreadable format
Response Measure:
TBD (Time/effort/resources required to circumvent security measures with probability of success)
Quality Attribute Scenario #14
Stimulus: A change occurs during the interview
Source of Stimulus: Interviewer
Environment: At runtime
Artifact: ZEN Client
Responses: Status is updated
Response Measure: The status is updated within 1 second
Quality Attribute Scenario #16
Stimulus: System crashes
Source of Stimulus: Internal to the system
Environment: At runtime
Artifact: ZEN Client
Responses: System restarts manually and returns to the last saved state
Response Measure: Return to the last saved state within 30 seconds from system start.
Quality Attribute Scenario #17
Stimulus: A question can be tagged with multiple tags
Source of Stimulus: Interviewer
Environment: At runtime
Artifact: ZEN Client
Responses: Support for efficient tagging
Response Measure: In less then 1 second per tag
Matrices
[edit] Architecture Views and Quality Attributes
This following matrix shows the mapping between views and high priority quality
attributes. A × indicates that a quality attribute is addressed by the mapped views.
Views and Quality Attributes Matrix
Viewtypes Views Quality Attributes
#4 #6 #7 #10 #11 #12 #14 #16 #17
Module
ZEN Server JSP Decomposition View ×
ZEN Tool Data Model ×
ZEN Client UI Decomposition View × × ×
C&C
ZEN Server High Level View ×
ZEN Server With Struts 2 ×
ZEN Client Interview Perspective × × × ×
ZEN Client Analysis Perspective × × ×
ZEN Client Initial Configuration × ×
ZEN Client Authentication × ×
[edit] Elements and Use Cases
The Element and Use Case Matrix explains the relation between the use cases and the two
major elements.
Element and Use Case Matrix
Elements
Use Cases
Choose Questi
on
Record
Answer
Synchronize
Engagement Data
Generate
Report
Generate
Template
Setup Engagement Data
Update SMIG
Information
Update Tag List
Sign In
Sign
Out
ZEN Client
× × × × × × ×
ZEN Server
× × × × × × ×
[edit] Client-Server Architecture
The following component and connector view shows the highest level of partitioning
the ZEN Tool in a client-server style.
The rationale of choosing the style is as follows:
A client-side desktop application is needed because the environment of using
the application may not have network access.
A centralize server-side application is needed because potentially large
amount of historical data needs to be accumulated for trend analysis.
The server-side application can be further divided into logic tier and data tier.
However, we do not expect heavy loading on the server-side application. The
client-server style is sufficient for current performance requirements.
The later sections will provide further decomposition of the architecture with multiple
architectural views.
Element Catalog
Element Description
ZEN Client ZEN Client is a standalone application that can be used during an interview. ZEN Client can operate in an environment without network access.
ZEN Server
ZEN Server is a standalone application that keeps track of all SMART engagements.
[edit] Allocation Architectural Viewtype
[edit] ZEN Tool Physical Deployment View
This view shows the physical elements of the ZEN Tool system and how they
communicate.
Element Catalog
Element Description
ZEN Server This is the physical server located at the SEI. It receives connections from multiple offsite Zen Client machines via a VPN connection. The communication can be either a direct data transfer or a web browser-based transfer.
ZEN Client Computer
This is the physical laptop in use at the SEI and at client locations. It can communicate with the ZEN Server. When at a client location, it does so in a direct data transfer or a
web browser-based transfer via a VPN connection.
ZEN Client This is the client portion of the ZEN Tool; it provides users the ability to conduct SMART interviews in an automated environment.
Web Browser This is a standard web browser.
Rationale
The system is partitioned into these components and connectors due to the
following:
Business Constraint: SMART Engagements involve SEI personnel traveling to
client locations and performing interviews. Data taken in these engagements
must be consolidated into a central repository. Thus we have chosen to use a
client-server system.
Quality Attribute: As indicated in Quality Attribute Scenario #13, all data
captured during a SMART Engagement must be 100% secure during transfer.
Therefore we use the HTTPS protocol for communication.
[edit] ZEN Server Deployment View
This view shows the primary components of the ZEN Server. It includes the web
server, which contains the Zen Server software component, and the MySQL
database being used as the primary repository.
Element Catalog
Element Description
ZEN Server Machine
This is the physical server located at the SEI. It contains a web server which contains the ZEN Server software component. It also contains a MySQL database.
Web Server This is the web server software component. It contains the ZEN Server and provides remote access to it.
ZEN Server This is the ZEN Server software component. It performs all of the critical repository functionality.
MySQL Database
This is the primary data repository for the ZEN Server. It contains all of the engagement information and all of the SMIG information.
Rationale
The ZEN Server is partitioned into these components due to the following:
Business Constraint: SMART Engagements involve SEI personnel traveling to
client locations and performing interviews. Data taken in these engagements
must be consolidated into a central repository. Thus to support a client-server
system, we have chosen to use a web server.
Business Constraint: The SMART team has no budget for professional
database software. Therefore the database choice must be free.
Quality Attribute: To promote modifiability, a database with complaint JDBC
drivers, such as MySQL, is used because it is common and well-documented.
[edit] ZEN Client Deployment View
This view shows the primary components of the ZEN Client. It includes the Zen
Client software component and a database being used as the primary local
repository.
Element Catalog
Element Description
ZEN Client Machine
This is the physical laptop used by SMART personnel to perform engagements. It can be used both at the SEI (without VPN access) and at client locations, using a VPN connection to communicate with the ZEN Server. It contains both the ZEN Client software component and a database.
ZEN Client This is the ZEN Client software component. It performs all of the critical interview functionality.
Database This is the primary data repository for the ZEN Client. It contains sets of Engagement data.
Rationale
The ZEN Server is partitioned into these components due to the following:
← Business Constraint: The SMART team has no budget for professional
database software. Therefore the database choice must be free.
← Quality Attribute: To promote modifiability, A database with complaint JDBC
drivers is used because it is common and well-documented.
[edit] ZEN Tool Deployment View
This view shows the deployment configuration of ZEN Tool.
This view highlights several architectural decisions:
← ZEN Client heavily depends on Eclipse RCP. See Rich Client Platform for the
trade-off analysis.
← ZEN Client requires obfuscation to prevent reverse engineering.
← ZEN Server depends on Struts 2, which is compliant to Java Servlet and
JavaServer Pages (JSP) standards. Therefore, any compliant servlet container
can be used to replace JBoss Web (Tomcat).
← Standards such as HTTP/HTTPS and JDBC are applied in both ZEN Client
and ZEN Server. Therefore, it is easy to replace HTTP/HTTPs implementation
and database.
← AJP is specifically for Apache HTTP Server communicating with JBoss Web
(Tomcat). Therefore, using other HTTP server, such as Microsoft IIS , will
require a different configuration.
Key: UML
Element Catalog
Element Description
Personal Laptop One or more laptops installed with ZEN Client communicate with the Central Server through HTTPS protocol.
Eclipse RCP Eclipse Rich Client Platform (RCP) provides the runtime environment for ZEN Client.
ZEN Client In this view, ZEN Client is more precisely defined as a plugin deployed inside Eclipse RCP. The binaries of ZEN Client have to be obfuscated to prevent reverse engineering.
Embedded This is an optional plugin that is intended to be the default database for ZEN Client.
Database See ZEN Client Data Store for the trade-off analysis.
Eclipse BIRT Eclipse BIRT is a reporting engine that can be used as a set of plugins in Eclipse RCP and a servlet in JBoss Web (Tomcat). Eclipse BIRT handles directly the JDBC connections.
External Database
ZEN Client can be configured to use an External Database with a compliant JDBC driver.
Central Server Central Server is located inside SEI. It has been specified that the server will run on Windows XP, but in fact, the deployment applies to any OS with a standard JDK/JRE.
Apache HTTP Server
The most popular web server. It communicates with JBoss Web using the Apache JServ Protocol (AJP).
MySQL The most popular open source database.
JBoss Application Server
JBoss Application Server is a J2EE 1.4 compliant application server.
JBoss JCA JCA stands for J2EE Connector Architecture. JBoss JCA is the implementation of JCA specification. The Data Source is deployed into JBoss using the JBoss JCA.
Data Source Data Source represents a JDBC data source that is available through a JNDI (Java Naming and Directory Interface) repository.
JBoss Naming Server
JBoss Naming Server (JBossNS) is implemented as a JNDI repository. ZEN Server looks up a JDBC data source from JBossNS.
JBoss Web (Tomcat)
JBoss Web is in fact an embedded Tomcat, a servlet container that ZEN Server is deployed into.
Struts 2 Struts 2 is a web application framework on which that ZEN Server is based. Its runtime behavior can be found in the ZEN Server With Struts 2 section.
ZEN Server In this view, ZEN Server is more precisely defined as a component (or a set of actions, interceptors, etc.) that resides in Struts 2. Detail run-time behavior can be found in ZEN Server With Struts 2 section.
ZEN Server Directory Structure
The following is a list of packages that comprise the server:
All packages ending with .test are test cases while others are described in the
individual Zen module pages.
All .builder packages are related with building the source code
All packages follow the Eclipse project conventions
[edit] Zen Common Directory Structure
The following is a list of packages that serve as a common resource for both the
client and the server:
All packages ending with .test are test cases while others are described in the
individual Zen module pages.
All .builder packages are related with building the source code
All packages follow the Eclipse project conventions
[edit] ZEN Client Directory Structure
The following is a list of packages that comprise the client:
← All packages ending with .test are test cases while others are described in the
individual Zen module pages.
← All .builder packages are related with building the source code
← All packages follow the Eclipse project conventions
[edit] Work Assignment View
Element Catalog
Component
Notes (Note: All components include UI, logic and data access wherever applicable)
Allen Marc Sajjad Session Somakala
ZEN Server
Authentication This component includes role based management aspects
×
SMIG Maintenance
Creating SMIG and exposing an interface to communication component for creating an XML structure of SMIG data
×
Reporting This includes report creation and report generation
× ×
Engagement Setup
Creating new engagement setup and exposing an interface to communication component for creating an XML structure of engagement setup data
×
Communication
This ensures secure ports listening for information. There should be a single point of entry
×
Consolidation This module consolidates the interview data from multiple users
×
Data Access Layer
This task involves ensuring that common tasks for database access like establishing connection etc. is provided as a utility. This task also involves verifying that the data model is normalized and does not have redundant information.
×
UI Layer This task involves ensuring ×
that the UI developed by all team members integrates well and it looks like one well developed UI
Installation and Configuration
This component is for installing the component and configuring it for use. Configuration should be available wherever applicable for later use during the lifetime of the tool
×
Administration Interface for creating roles, usernames and passwords on the server
×
ZEN Client
Authentication This component includes role based management aspects
×
Interview SMIG Navigation, storing answers, comments, tags, displaying risks
×
Interview - Status
Updating status on the UI based on the interview
×
Reporting This includes report generation
×
Template
This includes generating templates, component table and service table on the client. This is the Excel table (can be CSV)
×
Administration
Interface for connecting to server, downloading engagement setup, uploading interview data, downloading interview consolidated data
×
Communication
This ensures secure ports communicating with the server. There should be a single point of contact
×
Data Access Layer
This task involves ensuring that common tasks for database access like establishing connection etc. is provided as a utility. This task also involves verifying that the data model is normalized and does not have redundant information.
×
UI Layer
This task involves ensuring that the UI developed by all team members integrates well and it looks like one well developed UI
×
Installation and Configuration
This component is for installing the component and configuring it for use. Configuration should be available wherever applicable for later use during the lifetime of the tool
×
[edit] Module Architectural Viewtype
[edit] ZEN Tool Decomposition View
ZEN Tool is composed of two major modules: ZEN Client and ZEN Server.
Key: UML
Element Catalog
Element Description
edu.cmu.sei.smart.zen The module represents the ZEN Tool.
edu.cmu.sei.smart.zen.client The module represents the ZEN Client, which is a standalone GUI application.
edu.cmu.sei.smart.zen.server The module represents the ZEN Server, which is a centralize server.
[edit] ZEN Tool Module Dependency View
The ZEN Tool is composed of the a number of modules illustrated below.
NB: For both the client and server, two modules (more accurately, tasks) are not
shown:
The UI module, which consists of harmonizing the UI across multiple modules
on the client or server.
The installation and configuration task, that involves deploying the system to
the SEI environment.
NB: The ZEN Client Administration module currently only consists of the
synchronization of data between the client and the server, but in the future it may
take on added functionalities.
Element Catalog
Component
Notes (Note: All components include UI, logic and data access wherever applicable)
Allen Marc Sajjad Session Somakala
ZEN Server
Authentication This component includes role based management aspects
×
SMIG Maintenance
Creating SMIG and exposing an interface to communication component for creating an XML structure of SMIG data
×
Reporting This includes report creation and report generation
× ×
Engagement Setup
Creating new engagement setup and exposing an interface to communication component for creating an XML structure of engagement setup data
×
Communication
This ensures secure ports listening for information. There should be a single point of entry
×
Consolidation This module consolidates the interview data from multiple users
×
Data Access Layer
This task involves ensuring that common tasks for database access like establishing connection etc. is provided as a utility. This task also involves verifying that the data model is normalized and does not have redundant information.
×
UI Layer
This task involves ensuring that the UI developed by all team members integrates well and it looks like one well developed UI
×
Installation and Configuration
This component is for installing the component and configuring it for use.
×
Configuration should be available wherever applicable for later use during the lifetime of the tool
Administration Interface for creating roles, usernames and passwords on the server
×
ZEN Client
Authentication This component includes role based management aspects
×
Interview SMIG Navigation, storing answers, comments, tags, displaying risks
×
Interview - Status
Updating status on the UI based on the interview
×
Reporting This includes report generation
×
Template
This includes generating templates, component table and service table on the client. This is the Excel table (can be CSV)
×
Administration
Interface for connecting to server, downloading engagement setup, uploading interview data, downloading interview consolidated data
×
Communication
This ensures secure ports communicating with the server. There should be a single point of contact
×
Data Access Layer
This task involves ensuring that common tasks for database access like establishing connection etc. is provided as a utility. This task also involves verifying that the data model is normalized and does not have redundant information.
×
UI Layer
This task involves ensuring that the UI developed by all team members integrates well and it looks like one well developed UI
×
Installation and Configuration
This component is for installing the component and configuring it for use. Configuration should be available wherever applicable for later use during the lifetime of the tool
×
[edit] ZEN Server Layered View
This view shows the ZEN Server in a layered style.
It depicts three key architectural properties:
1. Higher-level layers are allowed to use any lower-level layers, but not the
reverse.
2. Higher-level layers depend on the services provided by the lower-level layers.
3. Higher-level layers may hide certainly functionalities in the lower-level layers,
but not all of them.
Element Catalog
Element Description
ZEN Server ZEN Server represents the web application layer that is based on JBoss Application Server.
JBoss Application Server
JBoss Application Server is a J2EE 1.4 compliant application server, but only the following modules will be used by the ZEN Server.
JBoss JMX JMX stands for Java Management Extension. JBoss JMX is the implementation of JMX specification. All the services in JBoss, such as JBoss Web and JBoss JCA are implemented as ManagedBean (MBean) that can be added to the JMX kernel.
JBoss JCA JCA stands for J2EE Connector Architecture. JBoss JCA is the implementation of JCA specification. The Data Source is deployed into JBoss using the JBoss JCA.
Data Source Data Source represents a JDBC data source that is available through a JNDI (Java Naming and Directory Interface) repository. JBoss has a bounded JNDI implementation, which is not shown in the view.
JBoss Web JBoss Web is in fact the Tomcat wrapped as a MBean. It's a servlet container that ZEN Server is deployed into.
Struts 2 Struts 2 is a web application framework that ZEN Server is based on. Its runtime behavior can be found in the ZEN Server With Struts 2 section.
JVM The Java Virtual Machine layer provides the Java Runtime Environment for the ZEN Client to run.
OS The Operation System layer provides the memory management, file I/O and other functionalities that are essential for the ZEN Client to run.
[edit] ZEN Client Layered View
This view shows the ZEN Client in a layered style.
It depicts three key architectural properties:
1. Higher-level layers are allowed to use any lower-level layers, but not the
reverse.
2. Higher-level layers depend on the services provided by the lower-level layers.
3. Higher-level layers may hide certainly functionalities in the lower-level layers,
but not all of them.
Element Catalog
Element Description
ZEN Client ZEN Client represents the rich client application layer that is based on Eclipse Rich Client Platform.
Eclipse Rich Client Platform
ZEN Client relies heavily on Eclipse Rich Client Platform. It extends the Generic Workbench to provide the views, editors and perspectives as described in the ZEN Client UI Decomposition View section.
Generic Workbench
The Generic Workbench manages the editors, views and perspectives. It provides the selection service for transmitting events between views and editors. One example of its runtime behavior can be found in the ZEN Client Interview Perspective section.
SWT SWT stands for the Standard Widget Toolkit. ZEN Client uses SWT to construct the user interface.
JFace JFace is a UI toolkit for handling common UI programming tasks. It is designed to work with SWT without hiding it. ZEN Client uses its data binding framework to decouple model from UI presentation.
Optional Plug-ins
Optional plug-ins such as help and update can be added to ZEN Client with ease.
Platform Runtime
The Eclipse's core platform runtime module provides the fundamental functionalities for the rich client application to run.
Equinox OSGi The Eclipse Equinox implements the OSGi R4 Framework.
JVM The Java Virtual Machine layer provides the Java Runtime Environment for the ZEN Client to run.
OS The Operation System layer provides the memory management, file I/O and other functionalities that are essential for the ZEN Client to run.
ZEN Server Decomposition View
The decomposition view represented here is the highest level of decomposition of
functionality of the ZEN server. The different functions have been grouped together
based on the activity they perform.
Key: UML
Element Catalog
Element Responsibilities
Authentication Authentication is responsible for verifying that the user or application accessing the server is a valid user of the system.
SMIG Maintenance
This process is responsible for modifications to the SMIG by supporting the following
Adding a question to the SMIG (and answers, risks, mitigation strategies)
Modifying an existing SMIG question (and answers, risks, mitigation
strategies)
Marking SMIG questions as no longer active
Engagement Setup
This process is responsible for creating the initial data setup for a particular engagement. This includes
Enter preliminary information about the engagement
Enter tags to be used for the engagement
Allow the user to download SMIG data for that engagement
Allow the user to download tag data for that engagement
Allow the user to download setup data for that engagement
Reporting This process is responsible for allowing the user to view reports on a browser. (TBD: And what else?)
Consolidation This process is responsible for consolidating the interview data across the interviewers per each engagement. This process will allow the user to upload the interview data and download the consolidated interview data.
Communication This process is responsible for communication between any outside component with the ZEN server. The outside component includes the ZEN client and browser access. This process must provide secure communication.
[edit] ZEN Server Reporting Decomposition View
The decomposition view splits reporting into two main functionalities, one for viewing
the reports (report generation) and the other for creating new reports (report
customization). Report generation and report customization use the Model-View-
Controller (MVC) pattern. This pattern allows us to separate the presentation layer
from the data access layer.
Key: UML
Element Catalog
Element Responsibilities
Report Generation
Report generation is used for generating reports and rendering it on the browser. This will use the MVC pattern. The functionality which needed to be provided for reports are
Filtering the data based on queries
Sorting (TBD)
Exporting to PDF and HTML (TBD)
Printing data
Report Customization
This process can be used to customize reports (TBD)
[edit] ZEN Server JSP Decomposition View
This view enumerates all the JSP pages.
See ZEN Server With Struts 2 for its runtime behavior.
Element Catalog
Element Responsibilities
Index.jsp This is the default page that is displayed to users who enter the web site's URL; it provides an authentication form with username and password fields for users to enter.
Main_Menu.jsp This is the main menu of functionalities that a user can choose from depending on the role he is authenticated in.
Error_Page.jsp This is a dynamically generated page that gives feedback to the
user about improper or inconsistent information entry (i.e. bad username or password), or server processing error.
Generate_Report.jsp
This page provides the user with a list of engagements to choose from, and a list of reports to generate for the chosen engagement. Note that only one type of report is generated at a time.
Report.jsp This is the resulting report generated by the server and displayed to the user, who can then print it from his browser.
Manage_SMIG.jsp
This page lists out all of the SMIG questions, and allows the user to choose to:
← add additional ones (which directs them to
Add_SMIG_Question.jsp).
← edit existing ones (which directs them to
Edit_SMIG_Question.jsp).
← mark a question as inactive for a particular version of the
SMIG.
← reactivate a question that was inactive for a particular
version of the SMIG.
Add_SMIG_Question.jsp
This page provides the following fields to add a new question:
← the SMIG version in which the question should be
activated.
← the text of the question.
← potential answers for the question with their associated
risks. Additional answers can be added or existing ones can
be removed.
← a multi-choice selection list of existing questions to which
the new one will be related.
The question ID will be automatically generated by the server.
The user will be returned to Manage_SMIG.jsp, and the
confirmation of the addition will be displayed on that page.
Edit_SMIG_Question.jsp This page provides the following fields to edit an existing
question:
← the SMIG version in which the question should be
activated.
← the text of the question.
← potential answers for the question with their associated
risks. Additional answers can be added or existing ones can
be removed.
← a multi-choice selection list of existing questions to which
the new one will be related.
The user will be returned to Manage_SMIG.jsp, and the
confirmation of the edits will be displayed on that page.
Manage_Engagement.jsp
This page lists out all of the engagements, and allows the user to choose to:
← add additional ones (which directs them to
Add_Engagement.jsp).
← edit existing ones (which directs them to
Edit_Engagement.jsp).
← delete existing ones (which directs them to
Delete_Engagement_Confirmation.jsp).
Add_Engagement.jsp This page provides the following fields to add a new engagement:
← engagement title.
← engagement description.
← the SMIG version associated with the engagement.
← customized tags associated with the engagement.
Additional tags can be added or existing ones can be
removed.
← a multi-choice selection list of current users that will
participate in the given engagement.
The engagement ID will be automatically generated by the
server, and the engagement's creation date and creator will be
deduced by the server as well.
The user will be returned to Manage_Enagement.jsp, and the
confirmation of the addition will be displayed on that page.
Edit_Engagement.jsp
This page provides the following fields to edit an existing engagement:
← engagement title.
← engagement description.
← the SMIG version associated with the engagement.
← customized tags associated with the engagement.
Additional tags can be added or existing ones can be
removed.
← a multi-choice selection list of current users that will
participate in the given engagement.
The user will be returned to Manage_Enagement.jsp, and the
confirmation of the edits will be displayed on that page.
Delete_Engagement_Confirmation.jsp
This page asks the user to confirm his choice to delete the selected engagement. Because an engagement, unlike a tag, consists of many pieces of data, and it is an important part of the interview process, the user must really be sure that he wants to delete one.
Manage_Users.jsp
This page displays all of the users of the ZEN Server and allows an administrator to:
← add users
← remove users
← change the information of a user (name, type, ...)
← reset the password of a user
Manage_Tags.jsp
This page displays all of the default tags and allows a user to:
← add more tags one at a time.
← select a single tag and edit it.
← select one to many tags and remove them.
The confirmation of the addition, edits, or removals will be
displayed on this page.
Consolidate_Interview_Data.jsp
This page displays all of the engagements and the users who have uploaded their interview reports for a particular engagement, and it allows the user to select an engagement with more than one interview report to consolidate all of them.
Download_Consolidated_Data.jsp This page displays that the consolidation process was successful and gives the user the ability to download the resulting consolidated report.
Download_ZEN_Client.jsp This page allows the user to download the ZEN Client tool onto his computer.
ZEN Client Decomposition View
The decomposition view represented here is the highest level of decomposition of
functionality of the ZEN client. The different functions have been grouped together
based on the activity they perform.
Key: UML
Element Catalog
Element Responsibilities
Authentication Authentication is responsible for verifying that the user or application accessing the server is a valid user of the system.
Interview This process is responsible for allowing the user to interview and capture data.
Browse through the SMIG
Record answers to SMIG questions
Apply tags to SMIG questions
Record comments on SMIG questions
Template Generation
This process generates a file (Microsoft Excel or CSV (TBD)) which will create the Service and Component Tables with default columns initially. When columns are tagged to be added to the template files, this process will be run by the user again. The original data will be retained and the new columns will be appended wherever applicable.
Reporting
Reporting on the ZEN client involves on report generation. Report generation is used for generating reports and rendering it on the client. The functionality which needed to be provided for reports are
Filtering the data based on queries
Sorting (TBD)
Exporting to PDF and HTML (TBD)
Printing data
Communication
This process is responsible for connecting to the server and uploading and downloading data. This includes
Downloading engagement setup data
Uploading interview data
Downloading consolidated data
Download system updates (TBD: For now this includes newly created reports)
[edit] ZEN Client Interview Decomposition View
The decomposition view represents the decomposition of the interview process of
the ZEN client. The different functions have been grouped together based on the
activity they perform.
Key: UML
Element Catalog
Element Responsibilities
Interview
This process is responsible for allowing the user to interview and capture data.
Browse through the SMIG
Record answers to SMIG questions
Apply tags to SMIG questions
Record comments on SMIG questions
SMIG Navigation
SMIG Navigation allows the client to navigate between questions. The questions can be navigated in the following ways
Sequentially
A new question can be triggered based on the answer chosen
Navigate to the last answered question
Search for a question and jump directly the one chosen by the user from the
search results
Information Gathering
Information Gathering allows the client to record interview data. This will follow the MVC pattern.
Record answers to SMIG questions
Apply tags to SMIG questions
Record comments on SMIG questions
Record data in the Service and Component Tables
Answer The UI process gets the answer from the user. This will follow the MVC pattern
Tag This process captures user's tag updates. This will follow the MVC pattern
Comment The process captures comment information stored by the user. This will follow the MVC pattern
Status The status of the answers which have been completed so far will be displayed to the user. This will follow the MVC pattern
[edit] ZEN Client Communication Decomposition View
Provide a rationale as to why a particular pattern, or the given architectural
representation is used.
Key: UML
Element Catalog
Element Responsibilities
Communication
This process is responsible for allowing the ZEN client to communicate with the ZEN server and transfer data. This data includes
← Engagement setup data
← Interview data
← Consolidated interview data
Engagement Setup Download
This process is responsible for downloading the engagment setup data from the server
Interview Data Upload Download
This process is responsible for uploading interview data from the Zen client to the ZEN server and downloading the consolidated interview data from the ZEN server
Remoting This process is responsible for communication between the ZEN client and the ZEN server
[edit] ZEN Client UI Decomposition View
Eclipse Rich Client Platform (Eclipse RCP) has been chosen as the framework for
ZEN Client. The rationale is documented in the Architecture Trade-off Analysis
section.
The ZEN Client UI is decomposed according to the Eclipse RCP framework and the
two major actors of the ZEN Client, Interviewer and Analyst.
Key: UML
Element Catalog
Element Description
Workbench The Workbench class is responsible for creating, managing and navigating its workspace resources, which include perspectives, views and editors. This class is part of the Eclipse RCP.
InterviewPerspective This InterviewPerspective class represents the initial user interface layout designed for the Interview Module in the Controller Layer.
AnalysisPerspective This class represents the initial user interface layout designed for the Report Module in the Controller Layer.
SynchronizationPerspective This class represents the initial user interface layout designed for the Synchronization Module in the Controller Layer.
SmigView
This class is responsible for displaying SMIG questions in a hierarchical way. It also provides search feature to assist the Interviewer to find a desired question quickly. The Interviewer selects a question and opens an AnswerEditor to record information.
AnswerEditor This class allows the Interviewer to record interview information, such as answer choices, comments and tags.
TagsView This class is responsible for displaying the tags. The state of checked tags changes according to what question is selected in the SmigView and in the editor area.
RiskView This class is responsible for displaying the associated risks to a selected answer choices in the AnswerEditor.
StatusView This class is responsible for showing the interview status. It displays the progress of each SMIG category.
TemplateView This class is responsible for displaying available report templates for the Analyst to choose from.
ReportEditor
This class is responsible for producing report according to the chosen template and the collected interview information. It uses the Ecliipse BIRT, an reporting engine chosen according the rationale documented in the Architecture Trade-off Analysis section.
EngagementView This class shows the locally available engagements. See Issues section for issues related to this class.
MessageConsole This class shows the communication between ZEN Client and ZEN Server.
ZEN Tool Data Model
This diagram shows how different data entities relate to each other.
Element Description
Engagement table
The table can be aptly described by the following SQL snippet:
Engagement (engagement_ID VARCHAR(64), engagement_Title VARCHAR(100),
engagement_Description VARCHAR(400), client_Name VARCHAR(400),
creation_Time BIGINT, modification_Time BIGINT, synch_Time BIGINT, repository
VARCHAR(400), engagement_State INT, PRIMARY KEY (engagement_ID))
Smig table
The table can be aptly described by the following SQL snippet:
Smig (smig_ID VARCHAR(64), smig_version VARCHAR(20), smig_description
VARCHAR(400), creation_Time BIGINT, last_Modification BIGINT, PRIMARY KEY
(smig_ID))
Category table
The table can be aptly described by the following SQL snippet:
Category (category_ID VARCHAR(64), category_name VARCHAR(500),
category_description VARCHAR(500), PRIMARY KEY (category_ID))
Question table
The table can be aptly described by the following SQL snippet:
Question (question_ID VARCHAR(64), question_Text VARCHAR(500),
question_short_name VARCHAR(500), default_next_question_ID VARCHAR(64),
isDisabled INT, PRIMARY KEY (question_ID))
Answer table
The table can be aptly described by the following SQL snippet:
Answer (answer_ID VARCHAR(64), answer_Text VARCHAR(400),
related_Question_ID VARCHAR(64), PRIMARY KEY(answer_ID))
Risk table
The table can be aptly described by the following SQL snippet:
Risk (risk_ID VARCHAR(64), risk_Text VARCHAR(400), PRIMARY KEY (risk_ID))
Tag table
The table can be aptly described by the following SQL snippet:
Tag (tag_ID VARCHAR(64), tag_Title VARCHAR (400), PRIMARY KEY (tag_ID))
Comment table
The table can be aptly described by the following SQL snippet:
Comment (comment_ID VARCHAR(64), comment_Text VARCHAR (10000),
PRIMARY KEY (comment_ID))
MitigationStrategy table
The table can be aptly described by the following SQL snippet:
Tag (tag_ID VARCHAR(64), tag_Title VARCHAR (400), PRIMARY KEY (tag_ID))
User table
The table can be aptly described by the following SQL snippet:
User(user_ID VARCHAR(64), user_description VARCHAR(400), encrypt_String
VARBINARY(200), random_Number VARBINARY(200), PRIMARY KEY (user_ID))
Other tables All other tables are simple M x N mapping tables.
[edit] ZEN Engagement State Maintenance
Engagement State Transition
The engagements in the server shall maintain one of the four different states
at any given time. The following state transition diagram dictates the rules,
conditions, and the sequence surrounding the change in states and the execution
of transitions.
All transitions to "closed" and "new" state should be decided by the engineer
responsible for the engagement setup component. This is because such
transitions are controlled and managed by that component.
State transition diagram:
Engagement State Description Table
State Code
Constant Name Description
1 NEW Represents a state where the subject engagement has not been downloaded, stored, or closed.
2 DOWNLOADED Represents a state where the subject engagement has been downloaded by one or more client(s).
6 STORED
Represents a state where client data for the subject engagement has been submitted by one or more client(s). Stored assumes that the engagement has been downloaded.
8 CLOSED_WITHOUT_DOWNLOADING Represents a state where a "new" engagement has been closed i.e. it was NOT downloaded or stored prior to closure.
10 CLOSED_AFTER_DOWNLOADING Represents a state where an engagement has been closed after it was DOWNLOADED by one or more clients.
14 CLOSED_AFTER_STORING Represents a state where an engagement has been closed after it was STORED by one or more clients.
[edit] Component & Connector Architectural Viewtype
[edit] ZEN Tool High Level C&C View
This high level C&C view shows the architectural styles employed in the design of
ZEN Tool.
← ZEN Tool is divided into two major elements, ZEN Client and ZEN Server.
← There is also an administration tool on the client side; however, it doesn't fit
within the RCP model, which is the main framework of the client. Therefore, the
administration tool is not represented in this view.
← ZEN Client is based on the Eclipse Rich Client Platform. Its design uses
heavily the vocabulary from Eclipse such as views, editors, actions and adapter
factories. See Rich Client Platform for the trade-off analysis.
← ZEN Server is based on the Servlet and JavaServer Page technologies.
Struts 2 is selected as the implementation framework. See Web Application
Framework for the trade-off analysis.
← ZEN Client communicates with ZEN Server using the XML-RPC over HTTPS
connector. See ZEN Client Remoting for the trade-off analysis.
← BIRT Reporting Engine is used in both ZEN Client and ZEN Server. See
Report Engine for the trade-off analysis.
← Data Access Objects are shared between ZEN Client and ZEN Server.
Element Catalog
Element Description
SelectionService SelectionService is part of the Eclipse RCP. It acts as an event bus that propagates events between view and editor objects.
Views/Editors Views provide users with a graphical representation of data and editors allow users to interact with that data.
Adapter Factories Adapter Factories are objects that link views and editors to the data access objects on which they depend to display and edit data for the user.
JFace Actions JFace Actions are the actions to be implemented to link ZEN client functionalities with services offered on the ZEN server.
Data Access Objects
Data Access Objects extract data out of the database, based on the specific command which is received. For example, download engagement setup would result in engagement data being extracted. On the other hand download consolidated data would return the user's data along with the consolidated data of all other users.
BIRT Reporting Engine
The Eclipse BIRT reporting engine generates the report display by contacting the database and using the report template file (*.rptdesign) for generating the report.
Report Templates (*.rptdesign)
These are the report design files which contain details about the report structure, namely what columns to show and how, the tables they communicate with in the database, database connection details (password is encrypted) and other presentation related details. It has an XML structure. (TBD: See how database communication details can be overriden with application's data).
Data This is the data store that holds the data of the ZEN Tool. This will be accessed via a JDBC connector.
XML-RPC over HTTPS
XML-RPC is a specification written to address sharing XML data irrespective of the operating system or the environment. Using HTTPS ensures secured communication between ZEN Client and ZEN Server.
Browser This is a standard web browser.
Https Secure connection over port 443.
Tomcat Request Dispatcher
The Request Dispatcher parses and executes http requests containing servlet commands. It determines which requests should be handled by the BIRT reporting engine and which ones should be sent to the Struts 2 actions.
Struts 2 FilterDispatcher
The Filter Dispatcher determines whether a request should invoke an action, and delegates control to the appropriate action if required.
Java Server Pages The JSP pages displayed to the browser upon authentication and authorization.
Struts 2 Actions The Actions are user-defined objects that implement the functionalities that are to be expressed. They may access database through the Data Access Object.
Business Objects These Business Objects are implemented as POJOs (Plain Old Java Objects), which can be invoked by the XML-RPC over HTTPS .
[edit] ZEN Server High Level View
This view shows the high level C&C view of ZEN Server.
Element Catalog
Element Type Responsibilities
Client CPU Computer The client CPUs run the ZEN Client and communicate with the ZEN Server to accomplish a number of server specific tasks.
Browser Browser Browsers communicate with the ZEN Server to accomplish a number of tasks.
Firewall Application The Firewall filters incoming traffic to the applications and databases residing on the server, in order a higher level of network security.
Tomcat Web Server
Web Server Tomcat is a servlet filter container that processes JSP tag commands from client or web page requests, and displays the result of those requests to the client or browser.
Tomcat Components
Web Server components
Contains a number of modules (servlets) provided by Tomcat, and that will be used to communicate with the Struts 2 Server.
Struts 2 Application Server
Struts 2 contains the ZEN Server functional components and processes requests that require an action to be executed (this may involve the database).
Database Database The database is a repository of all of the ZEN Server data.
[edit] ZEN Server With Struts 2
This view shows the runtime behavior of Struts 2, a web application framework that
ZEN Server uses to handle browser requests.
Element Catalog
Element Type Responsibilities
Browser Standard web browser
The browser submits the following requests to the server:
Interview consolidation requests to merge all of the
interview data for a given engagement.
Requests for engagement reports.
Modification requests for the SMIG.
Modification requests for tags.
Download requests for data.
Setup requests for new engagements.
SEI Firewall Application The Firewall filters incoming traffic to the applications and databases residing on the server, in order a higher level of network security.
Tomcat Web Server Web Server Tomcat is a servlet filter container that processes JSP tag commands from web page requests, and displays the result of those requests to the browser.
Tomcat Components Web Server components
Contains a number of modules (servlets) provided by Tomcat, and that will be used to communicate with the Struts 2 Server.
Servlet filters Objects
The servlet filters parse and execute http requests containing servlet commands. These filters are optional. If the ActionContextCleanUp filter is present, the FilterDispatcher will not clean up the ThreadLocal ActionContext once the Result is returned. If the ActionContextCleanUp filter is not present, the FilterDispatcher will cleanup all ThreadLocals.
FilterDispatcher Object The FilterDispatcher checks the ActionMapper to determine whether a request should invoke an action, and delegates control to the ActionProxy if an action is require. This filter IS required.
web.xml File The web.xml file describes all necessary framework components for web deployment, including servlet filters. This is a required configuration file.
Struts 2 Application Server
Struts 2 contains the ZEN Server functional components and processes requests that require an action to be executed (this may involve the database).
ActionMapper Object The ActionMapper determines whether a request requires an action to be invoked.
ActionProxy Object The ActionProxy refers to the ConfigurationManager to
determine which ActionInvocation to create to process the action, and it creates that ActionInvocation object.
ConfigurationManager Object The ConfigurationManager uses the information from struts.xml to tie an ActionInvocation with the action that it handles.
struts.xml File The struts.xml file initializes the ConfigurationManager and contains result/view types, action mappings, interceptors, and so forth. This is an optional configuration file.
ActionInvocation Object
The ActionInvocation is responsible for the command pattern implementation of Struts 2, which includes invoking interceptors and actions, and looking up the proper report type to create based on an Action's result code (mapped in struts.xml).
Interceptors Objects
Interceptors apply common functionality to the requests before or after an Action is executed, like validation and file upload handling. Interceptors act like listeners on an event bus, and they are called as soon as an action to which they are associated is "fired". The number and type of interceptors to run can be set for each Action individually or across all of them.
Action Objects The Action is a user-defined class that implements the functionality that is to be expressed. It may access database through the Data Access Object.
Data Access Object Objects The Data Access Object is responsible for accessing database through JDBC connection. Modification to database must be transactional, i.e., it's either all or nothing.
Database Database The Database is the central repository of the ZEN Server Tool (including engagement data, SMIG version, interview reports, ...).
Result Object The Result is an (optional) object that is created after the Action executes, and returned to the browser. The Result may optionally use a rendering Template (JSP, FreeMarker, ...).
Template File The Template is a file that is used to describe how the Result data should be rendered.
[edit] ZEN Client Initial Configuration
This view shows the ZEN Client's runtime behavior during initial configuration.
The view depicts three key architectural properties:
1. To enforce security, a secret (Authentication Text) is stored instead of actual
password.
2. The call-return connectors represent function calls inside one JVM. There is
no inter-process communication.
3. The security is implemented with random number generator (using
SecureRandom), cryptographic hash function (using MessageDigest) and
encryption/decryption (using Cipher).
The behavior information is expressed using a sequence diagram in the end of this
section.
Element Catalog
Element Description
ConfigurationDialog ConfigurationDialog allows the user to enter information during initial configuration. The information depicted here is focused on enabling the authentication process.
Other information may be still needed.
SecureRandom A secure random number generator. This is part of the JDK.
MessageDigest This object implements the one-way cryptographic hash function. Possible hash functions are SHA-256 and SHA-512. MD5 and SHA-1 are ruled out because of identified security flaw.
Cipher This object encrypts Authentication Text and Encryption Key #1 into the Encryption String by using Encryption Key #2.
AccountDAO AccountDAO is responsible for accessing the actual database table using JDBC.
AccountModel AccountModel stores the Username, Random Number and Encryption String in a database table.
[edit] Sequence Diagrams
The sequence of the initial configuration process is as follows:
← The user enters Username and Password through the
ConfigurationDialog.
← The Username is stored in plain text in the database.
← The system generates a Random Number and stores that number in the
database, associating it with the Username.
← The system now generates an encryption key (Encryption Key #2) using a 1-
way encryption algorithm based on the entered Password and the Random
Number associated with the Username. i.e., encryption_key =
Algorithm(password + random#)
← The system then takes the Encryption String (consisting of the
Authentication Key and the Encryption Key #1) and encrypts it using
Encryption Key #2.
← Finally, the system saves the encrypted Encryption String into the database,
associating it with the Username.
Key: UML
Element Catalog
Element Description
Username This is the username the user uses to log into the ZEN Client. It is recorded in the database in plain text.
Password This is the password the user uses to log into the ZEN Client. It is never recorded in the database, at all.
Random Number
This is a random number, called the "Salt", which is associated with a particular Username. It is stored in the database in plain text.
Authentication Text
This is a text string which is stored in the database in an encrypted format. It is used to verify that the user has entered the correct password.
Encryption Key #1
This is the key used for the encryption and decryption of the actual interview data. It is stored in the database in an encrypted format.
Encryption Key #2
This is the key generated from a 1-way encryption algorithm based upon the entered Password and the Random Number.
Encryption String
This is the concatenation of the Authentication Text and Encryption Key. The two elements are concatenated in plain text format, then the entire string is encrypted using Encryption Key #2.
[edit] ZEN Client Authentication
This view shows the ZEN Client's runtime behavior during authentication.
The view depicts three key architectural properties:
1. To enforce security, only the components that are required for performing
authentication are loaded into JVM.
2. The call-return connectors represent function calls inside one JVM. There is
no inter-process communication.
3. The security is implemented with cryptographic hash function and
encryption/decryption (using Cipher).
The Authentication module will compare user entered information with encrypted
keys stored in the database. The behavior information is expressed using a
sequence diagram (seen below this view).
Element Catalog
Element Description
ApplicationEntryPoint The system starts in this component. It calls the AuthenticationController to
enforce security.
AuthenticationController To enforce security, the authentication must be done in the AuthenticationController before loading any other resources.
LoginDialog LoginDialog allows user to enter user name and password.
Cipher This object decrypts Encryption String by using Encryption Key #2'.
AccountDAO AccountDAO is responsible for accessing the actual database table using JDBC.
AccountModel AccountModel stores the Username, Random Number and Encryption String in a database table.
MainApplicatoin This is an abstracted portion of ZEN Client that will be loaded after successful authentication.
[edit] Sequence Diagrams
The sequence of the authentication process is as follows:
User enters username & password through the LoginDialog.
The system checks the database for the Username. If it exists, it retrieves the
Random Number associated with that Username.
The system then generates a new encryption key (Encryption Key #2') using
a 1-way encryption algorithm based upon the entered Password and the
Random Number it retrieved.
The system now attempts to decrypt the Encryption String using the new
encryption key (Encryption Key #2').
The system then attempts to decouple the Challenge Authentication Text
from the Encryption String. If it matches the answer (Authentication Text) it
expects, the user is known to be valid.
The system then decouples the Encryption Key #1' from the Encryption
String.
Key: UML
Element Catalog
Element Description
Username This is the username the user uses to log into the ZEN Client. It is recorded in the database in plain text. It is initially created during installation, when the user selects login information.
Password This is the password the user uses to log into the ZEN Client. It is never recorded in the database, at all. However, it is used to create an encryption key which IS stored in the database (this will be explained later).
Random Number This is a random number, called the "Salt", which is associated with a particular username. It is stored in the database in plain text.
Authentication Text This is a text string which is stored in the database in an encrypted format. It is used to verify that the user has entered the correct password.
Challenge Authentication Text
This is the text extracted from Encryption String using Encryption Key #2'. It should match the original Authentication Text for a successful authentication.
Encryption Key #1' This is the key that is extracted from the Encryption String using the Encryption Key #2'.
Encryption Key #2' This is the key generated from one-way encryption algorithm based upon the entered Password and the Random Number retrieved from database.
Encryption String This is the Encryption String produced during initial configuration.
[edit] ZEN Client Interview Perspective
This architectural view shows the interaction between objects in the
InterviewPerspective of ZEN Client using an implicit invocation style.
The view depicts three key architectural properties:
1. The interaction between parts (the view and editor objects in Eclipse's term) is
decoupled by using the SelectionService, which is part of the Eclipse RCP.
2. The model is decoupled from view and editor objects by using the
ModelEventBus.
3. The view and editor objects do not directly access the model but through the
controller objects.
The behavior information is expressed using sequence diagrams in the end of this
section.
The related module decomposition view can be found in ZEN Client UI
Decomposition View section.
Element Catalog
Element Description
SelectionService SelectionService is part of the Eclipse RCP. It acts as an event bus that propagates events between view and editor objects.
SmigView SmigView is responsible for displaying SMIG data model using a tree. It announces selection events to the event bus indicating which question is selected.
AnswerEditor
AnswerEditor is responsible for providing the answering form and accepting response information. It announces activation events indicating an AnswerEditor has been activated. NavigationHistoryAction listens to these events to keep track the navigation history. It's possible to have multiple instances of AnswerEditor opened at the same time.
StatusView StatusView is responsible for displaying the progress of an interview. (To be refined)
SmigFilter SmigFilter is responsible for matching questions to key words. The matching results are then presented in the SmigView.
NavigationHistoryAction
NavigationHistoryAction keeps track of the navigation history. This object directly addresses the quality attribute scenario #6: Client provides information not related to current question, the person using the tool will navigate to the relate topic within 15 seconds and then be able to return to the previous question with one push of button.
AnswerAction
This object listens to the selection events from SmigView. If a question, instead of a category, is selected, the action is enabled. It uses the ResponseDAO object to retrieve responses from the database. The information is then passed to the AnswerEditor. It also activates the AnswerEditor.
SmigAdaptorFactory This object hooks up the SmigView object with the SMIG data model. It uses the SmigDAO object to retrieve SMIG data model from the database.
StatusAdaptorFactory This object hooks up the StatusView object with the response data model. It uses the ResponseDAO object to retrieve data from database and construct the status data model for the StatusView.
SaveAction This object is responsible for saving information gathered by the AnswerEditor to the database. The actual database access is done by the ResponseDAO object.
SmigDAO SmigDAO is responsible for accessing the actual database table using JDBC.
ResponseDAO ResponseDAO is responsible for accessing the actual database table using JDBC. Modification to ResponseModel must be transactional, i.e., it's either all or nothing.
Cipher ResponseDAO uses Cipher object to encrypt/decrypt data before storing it into database.
ModelEventBus ModelEventBus is an event bus that propagates model change events from model to view and editor objects.
SmigModel SmigModel is a set of database tables that represent the SMIG data model.
ResponseModel ResponseModel is a set of database tables that represent the responses to the SMIG questions.
[edit] Sequence Diagrams
[edit] Browse and Search
The Browse and Search sequence diagram shows the behavior of Interviewer
interacting with the SmigView.
Key: UML
[edit] Navigation History
The Navigation History sequence diagram shows the behavior of Interviewer
working on various AnswerEdiotr and the NavigationHistoryAction keeps track
the navigation history, thus enabling the back and forward actions.
Key: UML
[edit] Status Update
The Status Update sequence diagram shows the behavior of saving answers and
the corresponding status update.
Key: UML
[edit] ZEN Client Analysis Perspective
This view represents the runtime behavior of the AnalysisPerspective specified in
the ZEN Client UI Decomposition View section.
It depicts three key architectural properties:
← Eclipse BIRT has been chosen as the report engine. See Report Engine for
the trade-off analysis.
← Report format is customizable through modifying the Report Template
(*.rptdesign), but ZEN Client itself does not support the modification of Report
Template in normal operation context. See Business Context for the
representation.
← BIRTWebViewer handles the JDBC connection directly. Customization is
needed to support decryption of the data in ZENToolModel.
Element Catalog
Element Description
SelectionService SelectionService is part of the Eclipse RCP. It acts as an event bus that propagates events between view and editor objects.
TemplateView TemplateView is responsible for displaying the reports available using a tree. It announces selection events to the event bus indicating which report is
selected.
ReportAction ReportAction listens to the selection events from TemplateView. If a report, instead of the report group, is selected, the action is enabled. It instantiates a ReportEditor and passes the associated report object.
TemplateAdapterFactory
TemplateAdapterFactory hooks up the TemplateView object with the list of reports available. It reads the report list file (in xml format) and extracts the report category and report user friendly name, and the actual report name and instantiates a TemplateView object.
ReportEditor
ReportEditor is the UI page on which the report is rendered. The editor initializes a browser window where the generated report is displayed. It retrieves the name of the report file (stored as a part of the report object) and calls the PreviewBirtAction. It is possible to have multiple instances of ReportEditor opened at the same time, enabling multiple reports to be open at a time.
PreviewBirtAction PreviewBirtAction instantiates Eclipse BIRT report viewer with the link to the report design file and the browser which is instantiated in ReportEditor.
BIRTWebViewer BIRTWebViewer is the Eclipse BIRT reporting engine which generates the report display by contacting the database and using the report template file (*.rptdesign) for generating the report.
Report Template (*.rptdesign)
This is the report design file which contains details about the report structure, namely what columns to show and how, the table it communicates to in the database, database connection details (password is encrypted) and other presentation related details. It has an XML structure. (TBD: See how database communication details can be overriden with application's data)
Report List (*.xml) This is the file which contains details about the list of reports, the names of the files on the file systems, the names which will be used during display and the category under which they are listed. It has an XML structure.
ZENToolModel ZENToolModel holds the entire data of the ZEN Tool on which reports have to be generated. This will be accessed via a JDBC connector.
[edit] Usage on client side and server side
The Eclipse BIRT engine allows reports to be generated using a browser. On the
client side, this browser is embedded within the Eclipse RCP and uses the HTML
server functionality provided by the Eclipse BIRT engine internally.
The advantage is that the same report template file (*.rptdesign) can be used on the
server side as well with the same functionality as provided on the client side. This is
assuming that data model between the client and server for common functionality
are shared.
On the server side, BIRT allows the capability to interact with servlet mechanisms
and application servers like JBoss.
[edit] ZEN Client Synchronization Perspective
Brief description to be added.
Element Catalog
Element Description
ZEN Client ZEN Client initiates connection to the server. It provides credentials for authentication.
ZEN Server ZEN Server receives connections from the client. It has a HTTPS port open and listens for requests for clients.
Eclipse Workbench
Eclipse Workbench manages the editors, views and perspectives. It provides the selection service for transmitting events between views and editors.
JFace Actions JFace Actions are the actions to be implemented to integrate the ZEN client functionality, specifically here, the synchronization tasks using the JFace library provided within Eclipse.
Tomcat Tomcat is a servlet filter container that processes HTTP/HTTPS commands from client or web page requests, and returns/displays the result of those requests to the client or browser. .
Business Objects
Business Objects are implemented as POJOs (Plain Old Java Objects), which can be invoked by the XML-RPC over HTTPS.
XML-RPC over HTTPS
XML-RPC is a specification written to address sharing XML data irrespective of the operating system or the environment. Using HTTPS ensures secured communication between ZEN Client and ZEN Server.
Data Access
Data Access extracts data out of the database, based on the specific command which is received. For example, download engagement setup would result in engagement data being extracted. On the other hand download consolidated data would return the user's data along with the consolidated data of all other users.
Data This is the data store that holds the data of the ZEN Tool. This will be accessed via a JDBC connector.
[edit] Architecture Trade-off Analysis
[edit] Rich Client Platform
ZEN Client, a standalone desktop GUI application, has been identified as
possessing many important quality attributes, such as usability, security, availability
and performance. To efficiently build the GUI application, a readily available
framework is preferred. Rich Client Platform (RCP) is the realization of such
framework for building desktop GUI application. There are two notable RCPs in the
market: NetBeans Platform and Eclipse RCP.
In deciding which one to adopt, an evaluation based on quality attributes is conducted with the
following outcome.
RCP Usability Security Availability Performance
Eclipse Both are able to support creating usable UI.
Both have no build-in features for security. (Supported by underlying JDK/JRE.)
Both are proven and stable solutions in the market.
Good with it's native SWT approach.
NetBeans Not as good; depending on the implementation of JRE.
Additionally, the following factors are considered:
← Eclipse has a lager market share than NetBeans. (We use Eclipse in two of
our core courses.)
← Eclipse has a larger amount of sample projects that we can study and refer to.
In conclusion, Eclipse RCP seems to be more favorable than NetBeans Platform.
[edit] Report Engine
The three main open source tools considered were
← JasperReports
← BIRT
← OpenReports
The pros and cons for each are as follows
← JasperReports
← Pros
This is the most popular open source reporting tool (based on
the number of downloads). It supports reporting functionality and exports
to a variety of formats like PDF, HTML, XLS, CSV and XML.
← Cons
Web reporting functionality does not seem to be straightforward.
The idea is to export to HTML (or XML) and then use that for rendering.
← BIRT
← Pros
This is a reporting tool provided by Eclipse. It supports reporting
functionality and exports to formats like PDF and HTML.
Web reporting is straightforward. Same code can be used on the
client side (within an application) and on server side (to render on a
browser)
Easy to integrate in Eclipse RCP framework
← Cons
Export to CSV is not straightforward.
← OpenReports
← Pros
This is a web reporting tool. It supports reporting functionality
and exports to formats like PDF, HTML, CSV, XLS, RTF, and Image
It interacts with other reporting engines like BIRT and Jasper to
provide one unified reporting framework.
← Cons
Integrating OpenReports into a standalone application is not
straightforward.
Since all of the three tools have satisfactory support on modifiability, our decision
was based on the integration effort that each tool may require. BIRT turned out to be
a more favorable choice because it is easy to integrate into both Eclipse RCP-based
client side application and servlet-based server side application.
[edit] ZEN Client Authentication
Two significant alternatives are considered:
← Coupled with ZEN Server: The same account and password are used to
access both ZEN Client and ZEN Server. This will require the account and
password on ZEN Server to be deployed to ZEN Client in a secured and trusted
way. This approach promotes usability because the user only needs to
remember one account and password. In the Synchronize Engagement Data
use case, the user is spared from entering account and password to access ZEN
Server.
← De-coupled with ZEN Server: The user uses independent account and
password to access ZEN Client.
We chose de-coupled authentication because it greatly simplifies the architecture
and the security scenario is acceptable for our client.
[edit] ZEN Client Installation
A variety of alternatives are considered:
← Online distribution: The binary file of ZEN Client is stored on the ZEN Server
and can be accessed after entering the password. This approach promotes
security.
← Offline distribution: The binary file of ZEN Client is distributed manually,
through direct copying of the file. This approach is convenient but prohibits
security because there is no control on the binary file.
← Automatic installation program: ZEN Client is packaged as an automatic
installation program. This approach promotes usability because it's easy for the
user to use. However, it is difficult to develop and test.
← Archived file: ZEN Client is packaged as a archived file, such as a zip file.
This approach requires the user to unpack the archived file, so intuitively it can
also be easy the user to use. What's more, it's easier to develop and test.
← Java Web Start: A fairly sophisticated mechanism for automatic and secured
application deployment. However, our experiment showed that the integration
between Java Web Start and Eclipse RCP still requires significant hacking.
We chose online distribution with an archived file because online distribution
provides superior security control, and archived file is easier to develop and test.
[edit] ZEN Client Data Store
Three significant alternatives are considered:
← Flat file in XML format: Using flat file in XML format is extremely lightweight.
XML supports easier migration from one version to another, so it promotes
modifiability. Flat file can be easily encrypted, so it also promotes security.
However, using flat file will require the data to be decrypted and loaded into
memory, it prohibits scalability if there is a significant capacity requirement.
← Embedded database: Embedded database promotes security because other
processes are not allowed to access the database. It also promotes usability
because there is no upfront setup for the user. However, using embedded
database also has the scalability limitation, unless we can justify there won't be a
significant capacity requirement in ZEN Client.
← External database: External database promotes modifiability because
database can be easily switched as long as a compliant JDBC driver is used. It
also (indirectly) promotes scalability because sophisticated database can be
used. However, it requires some upfront setup tasks, which may be challenging
for nontechnical users.
We have decided that ZEN Client should support any database with a compliant
JDBC driver. Optionally, we should be able to bundle an embedded database as the
default database and give users an option to use an external database if so desired.
[edit] ZEN Client User Interface
See ZEN Client UI Decomposition View section to gain an overview of this tradeoff
analysis.
Two significant alternatives are considered:
← Integrate tags and risks into the AnswerEditor: tags and risks become an
integral part of the AnswerEditor.
← Separate tags and risks into viewers: Put tags into TagsView and risks into
RiskView.
We chose to separate tags and risks into viewers because it promotes both
modifiability and usability.
[edit] Database Record Id Generation
Two significant alternatives are considered:
← Automatic id generation: This method depends on the database providing
such functionality. It reduces implementation effort and promotes performance in
creating a new record.
← Universally Unique Identifier (UUID): This method decouple the dependency
on any specific database implementation; therefore, it promotes modifiability in
that any database can be used.
We chose to use UUID because modifiability outweighs ease of implementation and
performance in this particular decision.
[edit] ZEN Client Remoting
← Alternative A: XML-RPC
XML-RPC is an extensible format. Since the data is sent across using HTTP layer it
is easy to implement the communication between the client and the server. This
makes the code easy to maintain. Apache XML-RPC for Java provides a secure way
to establish communication between the client and the server. XML is standard and
XML-RPC is a specification written to address sharing XML data irrespective of the
operating system or the environment.
← Alternative B: SOAP
SOAP is an enhancement over XML-RPC. It offers a wide range of features over
XML-RPC including user defined data types, ability to specify the recipient, message
specific processing control etc. However to implement SOAP we need to add extra
components on both the server and the client side. For the purpose of this tool, the
requirement is simple file upload and download and the complexity of SOAP is not
necessary to accomplish the task when it can be efficiently and securely done by
XML-RPC.
[edit] Web Application Framework
There are probably too many web application framework out there. We only consider
the following two alternatives.
← Pure Servlet/JSP: Also known as "not using any web application framework at
all". It's possible to implement web application with only these two standards, but
the development effort will be high.
← Struts 2: Struts 2 is one of the popular web application frameworks that
implement design patterns such as front controller and command pattern.
We chose to use Struts 2 simply because it reduces development effort and allows
us to focus on the business logics.
[edit] Glossary
[edit] Acronyms for Institutions
← SEI - Software Engineering Institute
← MSE - Master of Software Engineering
← CMU - Carnegie Mellon University
← SMART - Service Migration And Reuse Technique
← SMIG - Service Migration Interview Guide (Refer to ZEN Tool Glossary below)
[edit] Architecture related acronyms
← QAW - Quality Attribute Workshop
← ACDM - Architecture Centric Development Method
[edit] Planning related acronyms
← ETVX - Entry Task Validation eXit
← PERT - Program evaluation and review technique
[edit] MSE acronyms
← MOSP - Middle Of Semester Presentation
← EOSP - End Of Semester Presentation
[edit] ZEN Tool Glossary
← SMIG - Service Migration Interview Guide. The SMIG contains the following
information in a hierarchical format
← Categories of topics to be discussed with the stakeholders
← Questions to be asked during a SMART Interview phase under each
category
← Predefined answer(s) for each question. There need not be an answer
at all, or there can more than one answer for each question
← Each pre-defined answer has 0..n risk factors associated with it.
← Each risk factor has 1..n mitigation strategies
← ZEN Tool - The software product delivered to the SEI. Performs functions in
both client and server roles.
← ZEN Client - The set of functions within the ZEN Tool which will be used by
the SEI personnel while on engagements. Functionality includes interview
capturing software and report generation. The ZEN client forms the client portion
of the ZEN tool.
← ZEN Server - The set of functions within the ZEN Tool which will be used as a
repository for engagement information. Functionality includes report generation,
SMIG maintenance, tag maintenance, and synchronization. The ZEN server
forms the server portion of the ZEN tool. The ZEN client communicates with the
ZEN server for various activities
← ZEN Users - The set of users authorized by the SEI to work on the SMART
process. This includes technical and non-technical users
← Interviewer - This person uses the ZEN Client before and during
engagement interviews. He can perform the following:
Download engagement file
Record answers to SMIG questions
Apply tags to SMIG questions
Record comments on SMIG questions
Browse through the SMIG
Record data in the Service and Component Tables
← Analyst - This person uses the ZEN Client and the ZEN Server after
an engagement. She can perform the following:
Upload interview data from the ZEN Client to the ZEN Server
Consolidate multiple sets of data from the same engagement on
the ZEN Server
Download consolidated interview data from the ZEN Server to
the ZEN Client
Produce reports on the ZEN Client and/or the ZEN Server
← Admin - This person uses the ZEN Client and the ZEN Server. This
person need not be a technical user. Any user who is aware of basic
computer usage and who is slightly knowledgeable about the SMART process
can be considered as an Admin. He can perform the following:
Create & set up engagement files on the ZEN Server
Create, modify, and delete custom tags
Associate a custom list of tags with a particular engagement file
Modify the SMIG in the following ways:
Add a question
Modify a question
Delete a question (this does not actually delete the
question, it simply marks it as inactive)
← Maintainer - TBD.
← Engagement - A set of interviews with a client company during which the
feasibility of migrating a legacy system to a SOA architecture is determined.
Involves the following phases (some of which are performed multiple times):
← Interview - A question and answer session with client representatives.
The client representatives can vary in role from managers to developers. This
is to ensure as much information is captured about the legacy system.
Involves use of the Interview set of functions of the ZEN Client. Once this
phase is complete, the Engagement shifts to the Analysis phase.
← Analysis - A review session covering all data captured to date. The
purpose of this phase is to identify risks for the migration. Involves use of the
reporting functions of both the ZEN Server and the ZEN Client. If further
information is needed to make a final recommendation, the Engagement
shifts back to the Interview phase. If a final recommendation can be made,
the Engagement shifts to the Final Report phase.
← Final Report - A consolidation session where a final evaluation of the
risks for the SOA migration is created and delivered to the client. Involves use
of the reporting functions of both the ZEN Server and the ZEN Client.
← Engagement File - This file is initially created prior to an engagement and
includes all information pertinent to the engagement. This includes:
← SMIG
← Any existing consolidated interview data
← Custom tags
← Interview Data - This represents all data captured during an Interview phase
of an Engagement. Includes answers to SMIG questions, comments, and applied
tags. Also includes all Service and Component table data captured. These pieces
are defined as follows:
← Answers - Each question in the SMIG currently has associated
predefined answers in multiple choice format. When the client answers a
question during the Interview phase, the Interviewer will select the closest
predefined answer.
← Comments - Because each question in the SMIG has predefined
answers, often clients will answer in a way that does not fully fit one of the
predefined answers. Therefore, the Interviewer may record comments on
each question which notes the actual answer and expands on any related
issues considered pertinent.
← Tags - When applying a comment to a question, the Interviewer may
feel that the answer to a particular question is very important in terms of the
SOA migration, and may wish to mark the answer for easy reference during
the Analysis phase. To do so, the Interviewer will apply one or more pre-
defined tags to the question. The tags will be reflected in the reports
generated in the Analysis phase. In addition, the tags are used to set up the
Service/Component table interface.
← SMART Templates - In addition to the SMIG questions, the Interviewer
will want to capture information which fall under the category of SMART
template. The service table and component table are examples of SMART
templates. (TBD: Are these the only two?) The ZEN Client will provide a
secondary interface to capture this information (the format of this interface
has yet to be determined).