WebSphere and .Net Interoperability Using Web Services

222 WebSphere and .Net Interoperability Using Web Services

1. Deploy Web service EAR file into the target application server.

2. Register the Web service on the Web Services Gateway with all required

options (protocol conversion, JAX-RPC handling, security, etc.) included in

the entry published to the UDDI registry.

The Web service consuming process is based on the following steps:

1. The client locates the service using the find service provided by the UDDI

registry. Because the UDDI is a J2EE application, client requests are

managed by the presentation layer provided with the UDDI registry, which is a

Web application exposed on the Internet through the WebSphere plug-in of

the HTTP server. The UDDI registry returns the found service, indicating as

the service endpoint the external one provided by the gateway.

2. The client performs the service binding asking the Gateway for the WSDL.

The gateway returns its own WSDL file.

3. The client sends the service invocation request to the Gateway, which routes

the invocation to the real internal Web service after applying all handlers and

protocol conversion, when needed. The response from the Web service is

then rerouted to the original client; also in this case, handlers and protocol

conversion are applied as needed.

10.3 Microsoft .Net Web service deployment model

Configuration of Microsoft .Net XML Web services follows the same paradigm

used by all ASP.NET Web applications, so the same concepts of deploying,

configuring, scaling, remoting and securing ASP.NET Web Applications can also

be applied for Web services.

The main software components are the Microsoft .Net platform itself and the

UDDI registry. In the following sections we first describe the UDDI Registry

features and than provide the overall deployment architecture.

10.3.1 Microsoft UDDI registry

Microsoft Enterprise Universal Description, Discovery, and Integration (UDDI)

Services is included in Windows Server 2003. Its main features are as follows:

򐂰 Supports versions 1.0 and 2.0 of the UDDI Programmer's API

򐂰 Has been developed using Microsoft ASP.NET and the Microsoft .Net

Framework

򐂰 Includes a Web interface with searching, publishing, and coordination

features

Chapter 10. Deploying Web services 223

򐂰 Takes advantage of the Active Directory service, providing the authentication

and authorization backbone for UDDI Services

Microsoft UDDI core entity names differ from the ones provided in the UDDI

specification. The relationship between names is shown in Table 10-1.

Table 10-1 Microsoft UDDI Core entity names

The installation consists of three components:

򐂰 Microsoft Internet Information Server 6.0 (IIS 6.0) - This is the Web server

housing the ASP.NET front end which is used to browse UDDI Services.

򐂰 Microsoft SQL Server 2000 or Microsoft SQL Server 2000 Desktop Engine

(MSDE) - This is the database to store the UDDI Services information.

򐂰 The Microsoft Management Console (MMC) management component, which

can be used to manage multiple UDDI Services from one administrative

console.

These components can be installed on the same machine or can be distributed

over the network. The distributed installation is available only with the Datacenter

or Enterprise Edition of Windows Server 2003 and does not support MSDE. A

distributed installation is configurable with different scalability topologies for each

component. For example, it is possible to have multiple Web servers with only

one database providing shared information.

10.3.2 Deployment architecture

The proposed architecture expects at least one classic front-end firewall with

packet filtering capabilities. This firewall must be configured, as usual, to allow

incoming HTTP requests on port 80 and HTTPS requests on port 443. More

robust firewall services able to inspect the HTTP and Web service request can

be obtained either by installing a more capable external firewall, an XML firewall,

or by using the URLScan tool from Microsoft.

Microsoft’s recommendation is: “A firewall should exist anywhere you interact

with an untrusted network, especially the Internet. It is also recommended that

you separate your Web servers from downstream application and database

UDDI.org Specification Microsoft UDDI Services

businessEntity Provider

businessService Service

bindingTemplate Binding

tModel tModel