05b - Network Layer Security IPSEC

Question 1

Give examples of applications of IPSEC

Answer 1

IKE (internet Key Exchange)

Question 2

What is the difference between transport mode and tunnel mode?

Answer 2

• Tunnel mode involves the entirety of the ESP trailer and transport-layer segment being encrypted and the block is then replaced with its ciphertext.
• Transport mode involves

Question 3

What is ESP?

Answer 3

Encapsulating Security Payload

- consists of an encapsulating header and trailer used to provide encryption or combined encryption/authentication.

Question 4

Why does ESP include a padding field?

Answer 4

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Question 5

What is a Replay Attack?

Answer 5

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Question 6

Where does IPSEC reside in the protocol stack?

Answer 6

in the OSI model, it resides in Layer 3 (the Network Layer)

Question 7

Present an overview of IP Security (IPSEC)

Answer 7

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Question 8

Explain the difference between transport mode and tunnel mode.

Answer 8

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Question 9

Understand the concept of Security Association (SA)

Answer 9

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Question 10

Explain the difference between Security Association Database and the Security Policy Database.

Answer 10

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Question 11

Present an overview of ESP

Answer 11

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Question 12

Summarize the traffic processing functions performed by IPSEC for out-bound packets and for in-bound packets.

Answer 12

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Question 13

Discuss the alternatives for combining SAs.

Answer 13

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Question 14

Present an overview of IKE

Answer 14

IKE - Internet Key Exchange.

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Question 15

Summarize the alternative cryptographic suites approved for use with IPSEC.

Answer 15

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