This is a transitive trust which is a two-way correlation routinely made among parent and child domains in a microsoft active directory forest and when a new domain is produced, it bonds resources with its parent domain by evasion in which allowing an valid user to access resources in together the child and parent.
Resource allocation is a function performed by control programs that manages computer resources, such as storage and memory. It is necessary for any application to be run on the system because the computer is required to allocate certain resources for it to be able to run once the user opens any program.