We don't have any applications on the Web. Should we upgrade anyway?

We are using CICS for MVS/ESA 4.1. We are planning to migrate to CICS TS 1.3. We don't have any applications on the Web. Our application is using a third-party product called Millennium which is being used by CICS and one application on DB2. There is no development or enhancement going on and the application is stable. So I want to know whether we migrate to CICS TS 1.3 or not? What is your suggestion on this matter?

Well, the first thing is that CICS 4.1 is out of service, and so you are going to have to move to CTS 1.3 or CTS 2.2. In both cases, the major thing to get right is the introduction of the Logger function - which will be an equal pain on either release.

If you have got the z/OS or OS/390 pre-reqs, then my recommendation is that you go for the latest release of CICS that fits.

You should consider skipping CTS 1.3, as there does not seem to be any benefit to you in going via an intermediate release as you will have to upgrade later on again (but that's a long time away). There are performance improvements available for the latest release of DB2 in CTS 2.2 which you might want to take advantage of. On the other hand, as you say things are stable, you don't need to use the latest Distributed Debugger and other API improvements in CTS 2.2. Java does not seem to interest you.

Declaring an interest as a member of the CICS Technical Strategy Community, I'd be inclined to goto CTS 2.2 as this gives you the performnce improvements and the latest APIs to support any potential future developments on your site......But I would say that, wouldn't I?

You need to be aware of forthcoming changes to the COBOL runtime environment related to LE within CICS, so you will have to ensure that your application is LE enabled/compliant. This applies to CTS 1.3 and CTS 2.2 - have a look at my LE paper on the CICS Web Site to brief yourself on these implications. It's probably better to get your application LE compliant (if it's not already) as part of the migration away from CICS 4.1 to prevent any future potential problems.