Web Services architectures from Halwet-packed

In May 1999, HP was the first to develop a Web Services platform under the name E-speak. Hewlett-Packard kept quiet as Microsoft, Oracle, and IBM responded, until March 2001 when it put a large number of software products together in two groups. 

The first of these groups was the NetAction suite, which contained products for Web Services, with 25 new products, including Bluestone. Bluestone software, which runs transactions for e-commerce, took an important role. Also brought under NetAction were E-speak, Chai (HP's version of embedded Java), and Open Call, an API bundle for call centers, and HP Security. Analysts say HP has possibilities as major player.
The Hewlett Packard Web Services Platform supports both Web Service interactions and Web Service implementation bindings via an architecture that addresses three key infrastructure services, as shown in the following illustration of the HP Web Services Platform.
 In addition, supporting functions that handle transactional semantics, security, availability, scalability,
monitoring, and management are provided by the underlying HP Total-e-Server platform.










BEA Systems
BEA Systems develop Web Services on the J2EE platform using the SOAP protocol. J2EE applications expose EJBs and
JMS destinations as Web Services. Private registries (possibly based on UDDI) are used to integrate with partners by some
applications. Typical enterprise application integration is based on the J2EE Connector Architecture ( JCA). Shawn Willet,
principal analyst at Sterling, commented, "The JCA technology is a bit immature and a lot of enterprise users may want to
go with a … more mature tool." BEA views their application platform as an integration platform.
Unlike other vendors, BEA (and Borland) uses Business Transaction Protocol (BTP) - an XML dialect for orchestrating
inter-enterprise business transactions that address the unique business-to-business (B2B) requirements. This protocol is stack
agnostic, so it can be easily implemented in conjunction with other standards such as ebXML or SOAP. For example, a
header can be added to the ebXML message envelope to carry the transaction context defined by BTP.
BEA offers two types of Web Services: remote procedure call (RPC)-style and message-style. The first type supports simple
Web Services (like stock quotes), is synchronous and is often given by vendors, while the second type is targeted toward a
loosely coupled, asynchronous model and is a key requirement for enterprise-class Web Services.
Security
Transactions
Availability
Scalability
Monitoring
Management
Tools
RPC-Style Web Services
You use a stateless session EJB to implement an RPC-style Web Service. When clients, for example, invoke the Web Service
specific to a service, they send parameter values to the Web Service, which executes the required methods, and then sends
back the return values. RPC-style Web Services are synchronous, meaning that when a client sends a request, it waits for a
response before doing anything else. This means that they are tightly coupled with a resemblance to traditional distributed
object paradigms, such as RMI and DCOM. One example is a computer screen showing stock quote ticker with an input
block, with which the user can get current information on a list of stock during trading hours.
Message-Style Web Services
This type of Web Service is loosely coupled and document-driven rather than being associated with a service-specific interface.
When a client invokes a message-style Web Service, the client typically sends it an entire document, such as a purchase
order, rather than a discrete set of parameters. The Web Service accepts the entire document, processes it, and may
or may not return a result message, such as a manager's acknowledgment of the order. This means the client does not wait
for the response before it can do something else. It can wait for it hours, days, or even weeks unless the system has some
kind of mechanism to alert the manager to respond within a time frame.
You can also use a message-style Web Service to request a record with the information you need all at once in an XML
message - last name, first name, social security number, and so on. This coarse-grained communication example is far better
than making three or more separate calls to get the record.