Network Map - Part 2

Exit Architecture

The exit architecture consists of a complex series of equipment that safely handles the information traveling to and from the campus network. Just like the core, different parts of the exit can share loads, so if one piece of equipment fails there is a redundant connection. Your packets will be directed around the fault and can still get in and out.

From the core, traffic first travels to an exit router. Then the exit router chooses where to direct the traffic and sends it toward either a firewall or a firewall bypass. A firewall is a device that analyzes data and protects the campus network from receiving harmful content from the Internet. Firewalls also protect the Internet from receiving any harmful content sent by a malicious user on campus.

Caching Switch and Firewall

Most of the traffic goes toward the firewall, but first it passes through a caching system. A special switch forwards the traffic, but also sends a copy of commonly used web pages to a caching device to decrease repetitious Internet traffic and provide faster response time to users.

Sometimes when traffic gets to the firewall, it is blocked instead of being sent through to the next router. The firewall blocks inbound and outbound nonapproved traffic that is malicious or destructive to the network.

Firewall Bypass

In some cases, the exit router will send specially approved traffic through the firewall bypass instead of through the firewall. This is one of the benefits of the campus exit architecture. Specially identified information traveling directly from one specific computer to another can bypass the firewall. This is a potential advantage for some approved administrative traffic, research information, and other forms of communication. Redirecting some traffic also protects the firewalls from becoming overloaded.

To the Internet

After the data goes through the firewall or the firewall bypass, it goes to a second exit router, which consolidates the traffic and sends it on to the Internet routers. The Internet routers are different from the other routers because they have a higher capacity to handle the larger load of all of the incoming and unfiltered outgoing campus traffic. These routers read the packets from your computer and direct them to the Internet.

Information coming into the university follows the opposite route, running from the exit architecture all the way back to your computer.