Web Science/Part1: Foundations of the web/Domain Name System/DNS address resolution/quiz

1 What is the difference between a forward and a reverse lookup

	The used transport layer protocol is different
	Forward lookups turn domain names to ip addresses
	Forward lookups turn ip addresses to domain names
	Reverse lookups turn ip addresses to domain names
	Reverse lookups turn domain names to ip addresses

2 Will all forward queries for domains be issued to a root server?

	Yes
	No

3 What is a problem that occurs when ISPs cache address resolution answers

	There is no problem
	The cache might get outdated
	Inconsistency might arise
	DNS stops to be a hierarchical protocol
	Caching and spreading results is prohibited in some countries due to copy right violations