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SOLA power - energise your legacy CICS |
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Article by William Hoffman, mainframe-upgrade.com
Published July 2006, Copyright © 2006 mainframe-upgrade.com
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SOLA power - energising your legacy CICS |
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The SOA gurus keep on shouting at us to expose our legacy applications as web services, telling us that this is the only way to gain the flexibility needed in our ever more fluid Business world. This is sound advice, but easier said than done. However, there are people who have been plugging away at this for some time, including a team, at Merrill Lynch who set out to answer some audacious questions - "Why not open up our legacy CICS applications as Web Services?, do it without using a Middle Tier?, and improve performance at the same time?"
The result of their work was X4ML (started back in 2001) and it is definitely worth a close look. Back in December 2005 SOA Software thought it so good that they bought the X4ML Mainframe Web Services platform from Merrill Lynch and branded it SOLA. Merrill Lynch continue to expand their use of SOLA and process over 2 million SOLA transactions daily through over 400 exposed CICS applications.
Performance
They claim a tenfold improvement in transaction times
No Mid Tier
The design successfully avoided a Mid Tier. Jim Crew, the project lead, said he was "sceptical of solutions that involve creating a middle tier" because "that it is one more black box which often becomes the source of failure".
SOA Software are now pushing SOLA as part of their overall SOA solution which can be purchased stand alone or part of a package with their other products SERVICE MANAGER, PARTNER MANAGER and NETWORK DIRECTOR.
The key thing to think about if you are tempted to buy in an SOA solution like SOLA is:
Do your legacy CICS transactions translate easily into services in the SOA model?. That is, will you create services that are Loosely Coupled, Stateless, Business Oriented and so on? (see my article on SOA Fundamentals for a more on this).
You'll need to do your analysis first, you do not want to create a load of services that do not provide you with the benefits of SOA - e.g. are not easily reusable or are not easily understandable to the Business. Having said that, it must be the case, I believe, that the core CICS transactions or groupings of CICS Transactions will, in many Enterprises, convert nicely into Web Services. This is because they perform the core Business Logic and will have usually be designed robustly.
More SOLA detail
SOLA analyses the COBOL source of a CICS transaction including the copybooks, and from that it can identify the inputs and outputs. This enables it then to go on and define the blueprint for the resulting Web Service(s). When finished it automatically creates the WSDL and publishes it in a UDDI directory.
After publication, the service becomes available in the run time environment and will execute the CICS transaction. A test harness is built in, so that the new service can be tested without any need to understand the distributed environment(s) that the service will reside in.
It is important to understand here that the CICS transaction continues to operate in its native mode as well as a web service. When you add the new service you cannot break the existing system, but as you would expect with SOA there is no duplicate code scenario to deal with.
SOLA handles conversational CICS applications as well, using tools that learn the key features of multi step transactions and their more complex inputs and outputs.
Conclusions
This product has the advantage of a proven track record at Merrill Lynch and there are plenty of facts and figures as well as opinions to back it in the SOLA links below. It will not be right for everyone, but for some it may be a relatively cheap way to expose a lot of mainframe CICS functionality as Web Services without creating a new middle tier. Its price is around the $125,000 mark.
SOLA links
SOLA is an SOA Software product - http://www.soa.com/ and you can find more on SOLA at their site at http://www.soa.com/index.php/section/products/sola/
Articles and blogs on SOLA :
Application Development Trends article: http://www.adtmag.com/article.aspx?id=18855
SOA Web Services Journal article: http://webservices.sys-con.com/read/205987.htm
http://www.mwdadvisors.com/blog/2006/05/soa-software-continues-its-acquisition.html
http://dev2dev.bea.com/blog/hoos/archive/2006/06/using_soa_to_cu.html
http://blogalization.nu/marketmachines/?p=911
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