If you want to verify VIP of any protocol let’s say SPI, I2C, AHB, AXI, etc. without DUT then you can create Testbench of the following Protocols as master and slave and connect them back to back once and verify your VIP and once you have DUT then replace it with master or slave VIP which you developed and verify the same. So, in this case, you simply have to make some changes in your connection. let’s say if you are using UVM methodology then you connect DUT instances with Interface signals in Top module.