Linked objects and crossover domains are different configuration
mechanisms that you can use to move data from one field in an application
to another field in a different application.
Data transfer options
Although similar in purpose, there are distinct differences
between the two configuration options that you can use to transfer
data from a field in one application to a field in another. These
data transfer options are based on either linked objects or on crossover
domains.
Crossing over domains to share data between applications
Using a crossover domain to display comments about an asset
in the Work Order Tracking application is similar to using linked
objects except that you use a crossover domain value to establish
a link between the Work Order and Asset objects and not a database
relationship. When using a crossover domain to copy data across applications,
you cannot edit the asset comment value in the destination application.