Routers are not very noticeable on internet-works, mainly because they usually do not have addresses such as Routers do not require having human-friendly addresses, because normal internet-work users not at all need to know that a router is there; they just want the connectivity it provides them.

The a few people who ever want to log directly into a router are members of the network team dependable for managing it. In TCP/IP networks—the protocol on which most internet-works run—routers recognize themselves to internet-works only with their IP addresses. For this reason, to log into a router you should first know that it available and after that what its IP address is. The network administrators responsible for the router will, of course, know this information.

The potential for misuse by hackers still exists. Routers continuously send messages to one another in order to update and manage the internet-works on which they operate. With the accurate skills and sufficient determination, a hacker could discover a router’s IP address and after that try to set up a Telnet connection to it. Given that routers are the links that stitch internet-works together, it is simple to know why Cisco and other internet-work equipment manufacturers design a lot of security measures into their products. As shown in Figure 4-8, security should check access to areas within an internet-work and to individual devices.