In reply to Maitri@07:
If you have only one agent, one driver, one sequencer, then you must start the sequences (2 sequences for RD and WR) with the same sequencer simultaneously (using fork/join_none). In your driver, you get the generated transactions which can be identified as RD or WR, and depending on type of transaction, you driver the virtual interface respectively. To drive RD and WR simultaneously, you must use fork/join_none in driver.
But from my perspective, I prefer 2 agents.