Answer below two questions in between 250 to 300 words:

a)In no less than 250 words, explain the difference between an access control list (ACL) that is used in routers to block traffic and firewalls.  What similarities do they share?  Respond to two other learners by the end of the week.

b)What are the main reasons why a VPN is the right solution for protecting the network perimeter? Do they also provide protection for mobile devices? If you do use a VPN, which one and why did you select that particular one?