What's the difference between a bridge and a router?
A1:
A bridge forwards data by physical address. A router forwards data by logical (IP) address.
Q2:
Why does core Internet primarily use dynamic routing?
A2:
It wouldn't be practical for a network administrator to type in static routing table information for a core router on the wildly complex and amorphous Internet.
Q3:
I want a switch that will allow me to forward Web traffic through a specific network interface. What kind of switch do I need?
A3:
A Layer 4 switch lets you forward traffic based on a port number associated with Web traffic. At a lower level, such as Layer 3, you could forward traffic based on network address, but you couldn't filter for a specific service at the address; such as HTTP TCP Port 80.