Dell Force10 MXL Blade MXL 10/40GbE Switch IO Module Configuration Guide - Page 261

14 IPv4 Routing The Dell Force10 operating software (FTOS) supports various IP addressing features. This chapter explains the basics of domain name service (DNS), address resolution protocol (ARP), and routing principles and their implementation in FTOS. • IP Addresses • Directed Broadcast • Resolution of Host Names • Addess Resolution Protocol (ARP) • Internet Control Message Protocol (ICMP) • UDP Helper Table 14-1 lists the defaults for the IP addressing features described in this chapter. Table 14-1. IP Defaults IP Feature DNS Directed Broadcast Proxy ARP ICMP Unreachable ICMP Redirect Default Disabled Disabled Enabled Disabled Disabled IP Addresses FTOS supports IP version 4, as described in RFC 791. It also supports classful routing and variable length subnet masks (VLSM). With VLSM, you can configure one network with different masks. Supernetting, which increases the number of subnets, is also supported. Subnetting occurs when a mask is added to the IP address to separate the network and host portions of the IP address. At its most basic level, an IP address is 32-bits composed of network and host portions and represented in dotted decimal format. For example, 10.214.87.131 is represented as: 00001010110101100101011110000011 For more information about IP addressing, refer to RFC 791, Internet Protocol. IPv4 Routing | 259