Domain Name System $($DNS$)$ uses client$/$server architecture to maintain and distribute hostnames and IP addresses on networks ranging from small local area networks to the Internet.

$($a$)$ Briefly explain the SIX $(6)$ key concepts of DNS$.(12$ marks$)$

$($b$)$ How does the NFS Automounter help to improve the performance and scalability of NFS$?(13$ marks$)$

$(25$ marks$)$

With the advent of Internet and Network technologies distributed Software System has become popular and important. Since the world is more concerned about Distributed System Development it becomes essential to discuss the Issues related to Distributed Software Systems. Explain in detail the FIVE $(5)$ challenges of distributed systems.

$(25$ Marks$)$