$1.$ In a three$-$tiered architecture, which type of switch is best used for connections to web servers.

$2.$ Which SDN plane moves traffic from switch port to switch port?

$3.$ Which network architecture technique are you using when you run a virtual router on a network?

Explain briefly network functions virtualization $($NFV$).$

$4.$ When you set private IP address ranges for servers in your cloud, what service model are you using?

$5.$ Briefly explain the mean time between failures $($MTBF$).$