In 2-3 lines describe the following 

• 9.1 Give examples of applications of IPsec.
• 9.2 What services are provided by IPsec?
• 9.3 What parameters identify an SA and what parameters characterize the nature of a particular SA?
• 9.4 What is the difference between transport mode and tunnel mode?
• 9.5 What is a replay attack?
• 9.6 Why does ESP include a padding field?
• 9.7 What are the basic approaches to bundling SAs?
• 9.8 What are the roles of the Oakley key determination protocol and ISAKMP in IPsec?