A – ESP-3DES-SHA

B – ESP-3DES-SHA1

C – ESP-3DES-SHA2

D- ESP-3DES

E – ESP-SHA-HMAC

*Answer: D

Explanation:

In the site-to-site VPN branch we see something like this but in the Tranform Set sub-branch, we see

so the answer should be ESP-3DES-SHA2 or ESP-3DES?

To answer this question, we should review the concept:

“Data confidentiality is the use of encryption to scramble data as it travels across an insecure media”. Data confidentiality therefore means encryption.

“The transform set is a group of attributes that are exchanged together, which eliminates the need to coordinate and negotiate individual parameters”. In the picture above, we can see 3 parts of the transform-set ESP-3DES-SHA2:

IPsec protocol: ESP

IPsec encryption type: 3DES

IPsec authentication: SHA2

The question wants to ask which algorithm is used for providing data confidentiality (encryption), therefore the answer should be D – ESP-3DES.