CertiGuide to Network+  9  Chapter 0101:  TCP/IP

Pop Quiz 0101.00 1 Static vs. Dynamic Routing

As discussed in the Addressing section, each network or LAN taking part in a TCP/IP-based internetwork such as the Internet has its own network number. These network numbers are used by routers to connect several networks together and to transmit the sent data to the proper receiver’s network.

Here’s an example. You are in your office in Dallas. You send an instant message to John in the San Jose office. Your LAN in Dallas doesn’t know how to reach John’s PC in the San Jose office. However, the router on your LAN knows which connection to use to send data to San Jose. So, it sends your instant message to San Jose, at which point the San Jose network sees it and, knowing where to find John’s PC, sends the data to the appropriate part of the San Jose LAN.

In order for this to work, somehow the router in Dallas has to get hold of the instant message. How does this happen, when you addressed the instant message to John’s PC, rather than to the router?

It happens because routing has been set up on the network, either explicitly or implicitly. As discussed earlier, routers are fence-sitters which have physical connections to more than one subnet or network, and know how to exchange information intelligently among all of those connections.

Pop Quiz 0101.00 1 Static vs. Dynamic Routing