Browse Prior Art Database

Use of attachments for more efficient structuring of Web Service interfaces to legacy systems

IP.com Disclosure Number: IPCOM000011563D
Original Publication Date: 2003-Mar-05
Included in the Prior Art Database: 2003-Mar-05
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Abstract

Disclosed is a technique that improves the efficiency of exploiting XML data on interfaces to high performance application servers.

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This is the abbreviated version, containing approximately 51% of the total text.

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  Use of attachments for more efficient structuring of Web Service interfaces to legacy systems

Web Services, the SOAP (Simple Object Access Protocol) on which they rely, and the XML data format are becoming the standards for distributed computing interoperation. Unlike previous interoperation protocols (such as IBM's* SNA) relatively little focus has been given to the efficiency of the information density in the messages or the efficiency of the analysis (parsing) of the data when serving a request - flexibility, function and useability are higher priorities.

     Web Services and SOAP present new solutions in an essentially mature problem space already populated with 'legacy' systems, and the marketplace is demanding that these legacy systems be enabled for the new services and protocol. The ubiquity of the network infrastructure supporting Web Services is also leading to the demand that legacy systems abandon other network and interoperation protocols so that a common infrastructure can be deployed and managed.

     When Web Services and/or SOAP is presented to high performance, highly tuned legacy systems, there is an obvious mis-match in the efficiency with which the SOAP request can be processed in comparison to the optimised (and often proprietary) legacy requests. The SOAP and Web Services standards are still evolving and highly tuned parsers that will narrow the performance gap are yet to emerge. These are unlikely to emerge until the applicable standards mature and stabilise. Until then the common, untuned parsers are the best option since they are maintained to be compatible with the evolving standards.

     When Web Service or SOAP enabling an application interface on a legacy system, such as CICS** Transaction Server, it must be decided how to map the native interface of the legacy application to the Web Service. The interface parameters may most naturally be transformed in the client prior to sending to the server, but the request is still a SOAP request, just with one (or a few) large binary parameters that require no further conversion on the server before being presented to the legacy application. These parameters are embedded in the XML document and contribute to the expense of parsing.

     Another problem would be presented by the adoption of SOAP or XML as a format for an IP based replacement for server-to-server communication. In this case, an approach could be taken to wrap the legacy datastream in a SOAP or XML wrapper. However, the processing of the SOAP request will involve running the parser over the SOAP wrapper and the legacy datastream.

     So there are a number of reasons that legacy system may need to employ SOAP but require some efficiency gains in handling the expense of parsing.

     This disclosure recognises that parsing a SOAP request is relatively expensive in CPU terms and this is a bad characteristic for many highly utilized server systems. It is further observed that minimising the size of the XML document to be parsed...