IP Routing

Conventions Used in This Book

Italic

Used for emphasis and the first use of technical terms, as well as for the names of networks and routers used in the examples.

Constant Width

Used for IP addresses.

Constant width italic

Used for replaceable parameter names in command syntax.

Code blocks are used throughout the text to make concepts concrete. Line numbers in the lefthand margins are used to refer to specific pieces of the code block. To avoid confusion, within each chapter the line numbers used in the code blocks start at 1 and continue consecutively through the end of the chapter. Code lines that are in bold but are not numbered are also of particular relevance to the surrounding text.

 NewYork#sh ip ospf interface
 ...
 Ethernet0 is up, line protocol is up
1  Internet Address 172.16.1.1/24, Area 0
2  Process ID 10, Router ID 172.16.251.1, Network Type BROADCAST, Cost: 10

   ...
 Serial0 is up, line protocol is up 
   Internet Address 172.16.250.1/24, Area 0 
   Process ID 10, Router ID 172.16.251.1, Network Type POINT_TO_POINT, Cost: 64

The use of “...” in the code block indicates that some lines (which were not useful in the discussion) have been omitted.

Tip

Indicates a tip, suggestion, or general note.

Warning

Indicates a warning or caution.