Linh Lam

A Software as a Service with Multi-tenancy Support for an Electronic Contract Management Application

In most commercial electronic contract management applications available today, different customized code base has to be developed, deployed and operated to support each tenant. Few advanced commercial electronic contract management applications use a single code base with configuration options to support multi-tenants. However, a separate instance of the code base still has to be deployed and operated for each tenant even in these applications. The business model of having to support a single application instance for each tenant makes an electronic contract management application and other critical business applications out of reach for most small and medium businesses (SMBs), in particular, the very small businesses (SVBs) because of its high development and maintenance cost. Recently, a new business model of a single application instance supporting multi-tenancy based on software as a service (SaaS) has emerged making expensive business applications more affordable for SMBs and SVBs for multi-tenancy [1]. In this paper, we present the first of a kind multi-tenancy SaaS electronic contract management application. We also describe several novel methods used in the metadata, security and shared services, as well as customization and tenant extensions modules to support multi-tenancy SaaS in this application. This multi-tenancy SaaS application has shown to benefit both the application service providers as well as their tenants. This new multi-tenancy SaaS model can reduce the application hosting cost and make the application more affordable to the tenants because of its capabilities in customization and scalability while continuing to support an increasing number of tenants. It furthers benefits tenants by saving their money and time with immediate access to the latest IT innovations and infrastructure improvements on a single application code base. Most end users of tenants have found their productivities increased, the contract transaction time accelerated, contractual errors reduced in using this multi-tenancy SaaS electronic contract management application as demonstrated in several ongoing IBM pilot programs serving more than ten tenants with over 3000 end users.

A Version-aware Approach for Web Service Directory

In real-world scenarios, the evolution of Web services to meet functional and non-functional changes ultimately leads to multiple versions of the same original service. Thus, design and implementation of version management techniques, such as version description, directory, etc, play a critical role in realizing the full promise of SOA. To address the version management issues in Web services, we propose a version-aware service model based on some architectural extensions to WSDL and UDDI. WSDL would be enhanced to describe the attributes of the service versions. UDDI would be augmented to use versions in a service directory with an event-based notification/subscription mechanism. We also design a proxy, residing in the service consumer side which can dynamically update the client application instance at runtime. We have implemented a prototype to demonstrate these models and used a weather forecast web service as an example to illustrate the usefulness of the proposed architecture.

Using an Interface Proxy to Host Versioned Web Services

Web services have become important building blocks of distributed applications and have matured to the point where service lifecycle issues such as version management are now paramount. However, there is a lack of versioning support in relevant standards and tools. We present an approach which leverages the existing WSDL service definition model to build a versioned service hosting solution. We distinguish between a Web service interface (published) version and its implementation version (private). We introduce the concept of a service interface proxy. This proxy, which can be generated automatically, implicitly defines the service interface version, and is published as the logical service endpoint. Client requests are routed dynamically by the proxy to appropriate implementation versions. We have implemented a prototype of our approach to demonstrate its applicability.

Dynamic Support for BPEL Process Instance Adaptation

Rapidly changing market conditions and IT systems are forcing companies to adapt their business processes more dynamically than in the past. Most current commercial BPMS products lack the full capability to support changing processes. To address this challenge, we discuss three aspects of dynamic adaptation in a BPM system: model-level, instance-level, and runtime environment changes. We focus on analyzing the patterns of the instance-level navigation changes, including the preconditions, actions and consequences of each change. Based on this analysis, we propose a system design for the runtime environment to support dynamic instance-level changes. We have implemented a prototype of such a system with the motivating scenarios to demonstrate the usefulness of our proposal.

A Version-aware Approach for Web Service Client Application

An increasing number of enterprises demonstrate that successful adoption of service oriented architecture (SOA) using Web services technologies enables them to build enterprise applications quickly and effectively. To align with changing business requirement, services need to adapt quickly, and eventually multiple versions of the same original service would coexist. To manage all these versions and ensure continuous availability to the service consumers, innovative techniques of version management for Web services become critical to realizing the full promise of SOA. To address the version management issues in Web services, we propose to include version-awareness to various aspects of Web services as an extension to the current SOA In particular, to minimize the impact of service changes on the service consumer side, we design a version-aware Web service client model (via an enhancement to the current JAX-RPC client model) which provides both consumer-aware and consumer-transparent invocation styles at build-time and dynamic service proxy generation at runtime. Leveraging the present implementation of the JAX-RPC service model, the versioned client APIs based on the new client model is designed to make the development process easy and intuitive. A prototype of this client model, implemented in Eclipse with an exemplary weather-forecast application, is introduced to demonstrate the usefulness of the proposed approach.

Identifying Data Constrained Activities for Migration Planning

Constant and rapid changes in the market place have inevitably brought changes to business process including the long running process. When changes are mandatory or require retroactive compliance, it may be necessary to migrate existing running process instances to a new version model. Current dynamic instance adaptation approach requires each instance to adapt to the changes individually. To support multiple instance migration across process models, we present an approach where we leverage model comparison technique; control and data flow analyses to identify data constraints for changed activities and identify potential migration points where we could migrate the instances. We then capture the migration point information in a migration plan which can later be used in the runtime environment to orchestrate the migration. We have implemented a prototype of our approach to demonstrate its applicability.

Predicting service delivery cost for non-standard service level agreements

One of the key promises of IT strategic outsourcing is to deliver greater IT service management through lower cost. However, this raises a critical question on how to predict service delivery cost during the service engagement phase where nonstandard service level agreements (SLAs) are negotiated and detailed service modeling data are not available. In this paper we propose a modeling framework that uses queueing model based approaches to estimate the impact of SLAs on the delivery cost. We further propose a set of approximation techniques to address the complexity of service delivery and an optimization model to predict the delivery cost subject to service level constraints and service stability conditions. We demonstrate the applicability of the proposed methodology using data from a large IT service delivery environment.

Modeling the Impact of Service Level Agreements During Service Engagement

One of the key promises of IT strategic outsourcing is to deliver greater IT service management through lower cost. However, this raises a critical question: How can one predict the service delivery cost that will deliver the promised service level agreements (SLAs)? This is particularly challenging since such prediction is mostly needed during the service engagement phase where the SLAs and the delivery cost are negotiated, and the detailed service modeling data are not available. In this paper, we propose a modeling framework that uses queueing-model-based approaches to estimate the impact of SLAs on the delivery cost. We further propose a set of approximation techniques to address the complexity of service delivery and an optimization model to predict the delivery cost subject to service-level constraints and service stability conditions. We demonstrate the applicability of the proposed methodology using data from a large IT service delivery environment.

SLA impact modeling for service engagement

During the customer engagement phase it is critical for the service providers to estimate the impact of service level constraints on service personnel needs. However, it is often difficult due to the implication from customer workload. In this paper we propose an SLA impact evaluation methodology that uses queueing models to quantitatively evaluate the impact of SLAs to the engagement cost model.

A Web-based and Email Driven Electronic Contract Management System

In an enterprise, managing and processing an electronic contract often involves a number of contract administrators and representatives in the enterprise, and their counter parts in their suppliers, business partners or their customers to carry out a large number of complex manual tasks in sequences during the life cycle of electronic contract. In most commercially available electronic contract management systems, users either waste a lot of their time in monitoring their task lists for their turns to act on their electronic contracts or most electronic contracts simply stay idle for most of the time if users only check their task lists once a while. In addition, these manual tasks are often tedious and may cause security faults. In this paper, we present a Web-based and email driven electronic contract management system that supports both internal and intra-enterprises workflows, and with multi-tenants hosting capability. This system enables a user to act on the next task in a sequence of tasks to process a particular electronic contract immediately after the other user has completed the previous task in the same sequence of tasks by sending out email notifications to alert or remind the user to take action on the task. We also describe several novel methods to automate some manual and tedious tasks, such as watermarking signature information on the signed electronic contract and life cycle management, in this paper. Most users have found their productivities improved, the electronic contract transaction time accelerated, contractual errors reduced and many other benefits by using this electronic contract management system in several IBM pilot programs.