This section describes how you can migrate several types of existing application to use channels and containers rather than communication areas (COMMAREAs).
It’s possible to replace a COMMAREA by a channel with a single container. While this may seem the simplest way to move from COMMAREAs to channels and containers, it’s not good practice to do this.
Also,
be aware that a channel may use more storage than a COMMAREA designed to pass
the same data. (See Designing a channel: best practices.)
Because you’re taking the time to change your application programs to exploit this new function, you should implement the "best practices" for channels and containers—see Designing a channel: best practices. Channels have several advantages over COMMAREAs (see Benefits of channels) and it pays to design your channels to make the most of these improvements.