Accessing components bottom up using set_config_* and get_config_* in UVM !!!

One of the requirements in verification is to access variable bottom up  in the hierarchy this can be done in UVM using set_config_*  and get_config_*methods. In bottom up access you need to use hierarchical reference like  uvm_test_top.set_config_*  or  uvm_test_top.get_config_*  from the component in the lower level hierarchy to access component in top level hierarchy.  Top down access does not require the hierarchical reference to uvm_test_top , set_config_* and get_config_* can be used directly.