IP Addressing and Subnetting for New Users （为新用户,IP地址和子网划分）.pdf

Contents Introduction Prerequisites Requirements Components Used Additional Information Understand IP Addresses Network Masks Understand Subnetting Examples Sample Exercise 1 Sample Exercise 2 VLSM Example VLSM Example CIDR Appendix Sample Config Router A Router B Host/Subnet Quantities Table Related Information Introduction This document provides basic information needed in order to configure your router for routing IP, such as how addresses are broken down and how subnetting works. You learn how to assign each interface on the router an IP address with a unique subnet. There are examples included in order to help tie everything together. Prerequisites Requirements Cisco recommends that you have a basic understanding of binary and decimal numbers. Components Used This document is not restricted to specific software and hardware versions. The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command. Additional Information If definitions are helpful to you, use these vocabulary terms in order to get you started: Address - The unique number ID assigned to one host or interface in a network. Subnet - A portion of a network that shares a particular subnet address. Subnet mask - A 32-bit combination used to describe which portion of an address refers to the subnet and which part refers to the host. Interface - A network connection. If you have already received your legitimate address(es) from the Internet Network Information Center (InterNIC), you are ready to begin. If you do not plan to connect to the Internet, Cisco strongly suggests that you use reserved addresses from RFC 1918 . Understand IP Addresses An IP address is an address used in order to uniquely identify a device on