What are Transport CO files and Transport Data Files?
On all operating systems, a special file structure for transport data, logs, temporary data, and transport control data is required where SAP instance is running.
The file structure is operating system-dependent, but SAP has tried to keep these differences as small as possible.
Transport path needs a transport path directory, which is called /usr/sap/trans under UNIX. You can also use any other directory in the file system, but it must exist on every machine in your network where a SAP instance is running (UNIX: mounted, Windows: share). If this is not the case, you cannot install a transport system that runs automatically.
The transport directory must have the following subdirectories:
Contains the transport data
Contains information on change requests (different steps of a change request and their exit codes)
With the data and cofiles , you can easily trasport TR's between systems without having a route established between them.
Hope this helps.